Understanding omega-3 polyunsaturated Fatty acids.

Understanding omega-3 polyunsaturated Fatty acids.

Calder PC, Yaqoob P.

Institute of Human Nutrition School of Medicine, Southampton General Hospital, Southampton, UK. pcc@soton.ac.uk.

Current intakes of very long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are low in most individuals living in Western countries. A good natural source of these fatty acids is seafood, especially oily fish. Fish oil capsules contain these fatty acids also. Very long-chain omega-3 fatty acids are readily incorporated from capsules into transport (blood lipids), functional (cell and tissue), and storage (adipose) pools. This incorporation is dose-dependent and follows a kinetic pattern that is characteristic for each pool. At sufficient levels of incorporation, EPA and DHA influence the physical nature of cell membranes and membrane protein-mediated responses, lipid-mediator generation, cell signaling, and gene expression in many different cell types. Through these mechanisms, EPA and DHA influence cell and tissue physiology and the way cells and tissues respond to external signals. In most cases the effects seen are compatible with improvements in disease biomarker profiles or health-related outcomes. As a result, very long-chain omega-3 fatty acids play a role in achieving optimal health and in protection against disease. Long-chain omega-3 fatty acids not only protect against cardiovascular morbidity but also against mortality. In some conditions, for example rheumatoid arthritis, they may be beneficial as therapeutic agents. On the basis of the recognized health improvements brought about by long-chain omega-3 fatty acids, recommendations have been made to increase their intake. The plant omega-3 fatty acid, alpha-linolenic acid (ALA), can be converted to EPA, but conversion to DHA appears to be poor in humans. Effects of ALA on human health-related outcomes appear to be due to conversion to EPA, and since this is limited, moderately increased consumption of ALA may be of little benefit in improving health outcomes compared with increased intake of preformed EPA + DHA.

Use of multivitamin supplements in relation to allergic disease in 8-y-old children

Use of multivitamin supplements in relation to allergic disease in 8-y-old children
[Dietary supplements]
from American Journal of Clinical Nutrition current issue by Marmsjo, K., Rosenlund, H., Kull, I., Hakansson, N., Wickman, M., Pershagen, G., Bergstrom, A.

Background: Multivitamins are frequently consumed by children, but it is unclear whether this affects the risk of allergic disease.

Objective: We sought to study the association between multivitamin supplementation and allergic disease in 8-y-old children.

Design: Data were obtained from a Swedish birth cohort study. Information on lifestyle factors, including use of vitamin supplements, environmental exposures, and symptoms and diagnoses of allergic diseases, was obtained by parental questionnaires. In addition, allergen-specific IgE concentrations of food and airborne allergens were measured in blood samples collected at age 8 y. A total of 2423 children were included in the study. The association between use of vitamin supplements and the selected health outcomes was analyzed with logistic regression.

Results: Overall, no strong and consistent associations were observed between current multivitamin use and asthma, allergic rhinitis, eczema, or atopic sensitization at age 8 y. However, children who reported that they started taking multivitamins before or at age 4 y had a decreased risk of sensitization to food allergens (odds ratio: 0.61; 95% CI: 0.39, 0.97) and tendencies toward inverse associations with allergic rhinitis. In contrast, there was no consistent association among children who started to use multivitamins at or after age 5 y.

Conclusion: Our results show no association between current use of multivitamins and risk of allergic disease but suggest that supplementation with multivitamins during the first years of life may reduce the risk of allergic disease at school age.

Dietary protein and bone health: a systematic review and meta-analysis

Dietary protein and bone health: a systematic review and meta-analysis [Bone metabolism]
from American Journal of Clinical Nutrition current issue by Darling, A. L, Millward, D J., Torgerson, D. J, Hewitt, C. E, Lanham-New, S. A

Background: There has been a resurgence of interest in the controversial relation between dietary protein and bone health.

Objective: This article reports on the first systematic review and meta-analysis of the relation between protein and bone health in healthy human adults.

Design: The MEDLINE (January 1966 to September 2007) and EMBASE (1974 to July 2008) databases were electronically searched for all relevant studies of healthy adults; studies of calcium excretion or calcium balance were excluded.

Results: In cross-sectional surveys, all pooled r values for the relation between protein intake and bone mineral density (BMD) or bone mineral content at the main clinically relevant sites were significant and positive; protein intake explained 1–2% of BMD. A meta-analysis of randomized placebo-controlled trials indicated a significant positive influence of all protein supplementation on lumbar spine BMD but showed no association with relative risk of hip fractures. No significant effects were identified for soy protein or milk basic protein on lumbar spine BMD.

Conclusions: A small positive effect of protein supplementation on lumbar spine BMD in randomized placebo-controlled trials supports the positive association between protein intake and bone health found in cross-sectional surveys. However, these results were not supported by cohort study findings for hip fracture risk. Any effects found were small and had 95% CIs that were close to zero. Therefore, there is a small benefit of protein on bone health, but the benefit may not necessarily translate into reduced fracture risk in the long term.

Dietary fat intake and subsequent weight change in adults: results from the European Prospective Investigation into Cancer and Nutrition cohorts

Dietary fat intake and subsequent weight change in adults: results from the European Prospective Investigation into Cancer and Nutrition cohorts
[Nutritional epidemiology and public health]

from American Journal of Clinical Nutrition current issue by Forouhi, N. G, Sharp, S. J, Du, H., van der A, D. L, Halkjaer, J., Schulze, M. B, Tjonneland, A., Overvad, K., Jakobsen, M. U., Boeing, H., Buijsse, B., Palli, D., Masala, G., Feskens, E. J., Sorensen, T. I., Wareham, N. J

Background: It is unclear from the inconsistent epidemiologic evidence whether dietary fat intake is associated with future weight change.

Objective: The objective was to assess the association between the amount and type of dietary fat and subsequent weight change (follow-up weight minus baseline weight divided by duration of follow-up).

Design: We analyzed data from 89,432 men and women from 6 cohorts of the EPIC (European Prospective Investigation into Cancer and Nutrition) study. Using country-specific food-frequency questionnaires, we examined the association between baseline fat intake (amount and type of total, saturated, polyunsaturated, and monounsaturated fats) and annual weight change by using the residual, nutrient density, and energy-partition methods. We used random-effects meta-analyses to obtain pooled estimates across centers.

Results: Mean total fat intake as a percentage of energy intake ranged between 31.5% and 36.5% across the 6 cohorts (58% women; mean ± SD age: 53.2 ± 8.6 y). The mean (±SD) annual weight change was 109 ± 817 g/y in men and 119 ± 823 g/y in women. In pooled analyses adjusted for anthropometric, dietary, and lifestyle factors and follow-up period, no significant association was observed between fat intake (amount or type) and weight change. The difference in mean annual weight change was 0.90 g/y (95% CI: –0.54, 2.34 g/y) for men and –1.30 g/y (95% CI: –3.70, 1.11 g/y) for women per 1 g/d energy-adjusted fat intake (residual method).

Conclusions: We found no significant association between the amount or type of dietary fat and subsequent weight change in this large prospective study. These findings do not support the use of low-fat diets to prevent weight gain.

Green tea consumption is associated with depressive symptoms in the elderly

Green tea consumption is associated with depressive symptoms in the elderly
[Nutritional epidemiology and public health]

from American Journal of Clinical Nutrition current issue by Niu, K., Hozawa, A., Kuriyama, S., Ebihara, S., Guo, H., Nakaya, N., Ohmori-Matsuda, K., Takahashi, H., Masamune, Y., Asada, M., Sasaki, S., Arai, H., Awata, S., Nagatomi, R., Tsuji, I.

Background: Green tea is reported to have various beneficial effects (eg, anti–stress response and antiinflammatory effects) on human health. Although these functions might be associated with the development and progression of depressive symptoms, no studies have investigated the relation between green tea consumption and depressive symptoms in a community-dwelling population.

Objective: The aim of this study was to investigate the relations between green tea consumption and depressive symptoms in elderly Japanese subjects who widely consumed green tea.

Design: We conducted a cross-sectional study in 1058 community-dwelling elderly Japanese individuals aged ≥70 y. Green tea consumption was assessed by using a self-administered questionnaire, and depressive symptoms were evaluated by using the 30-item Geriatric Depression Scale with 2 cutoffs: 11 (mild and severe depressive symptoms) and 14 (severe depressive symptoms). If a participant was consuming antidepressants, he or she was considered to have depressive symptoms.

Results: The prevalence of mild and severe and severe depressive symptoms was 34.1% and 20.2%, respectively. After adjustment for confounding factors, the odds ratios (95% CI) for mild and severe depressive symptoms when higher green tea consumption was compared with green tea consumption of ≤1 cup/d were as follows: 2–3 cups green tea/d (0.96; 95% CI: 0.66, 1.42) and ≥4 cups green tea/d (0.56; 95% CI: 0.39, 0.81) (P for trend: 0.001). Similar relations were also observed in the case of severe depressive symptoms.

Conclusion: A more frequent consumption of green tea was associated with a lower prevalence of depressive symptoms in the community-dwelling older population.

Effect of a dietary intervention and n-3 fatty acid supplementation on measures of serum lipid and insulin sensitivity in persons with HIV

Effect of a dietary intervention and n-3 fatty acid supplementation on measures of serum lipid and insulin sensitivity in persons with HIV [AIDS and other wasting syndromes]

from American Journal of Clinical Nutrition current issue by Woods, M. N, Wanke, C. A, Ling, P.-R., Hendricks, K. M, Tang, A. M, Knox, T. A, Andersson, C. E, Dong, K. R, Skinner, S. C, Bistrian, B. R

Background: Elevated serum triglyceride and low HDL-cholesterol concentrations have been reported in persons with HIV.

Objective: The effect of a dietary intervention plus n–3 (–3) fatty acid supplementation on serum triglycerides and markers of insulin sensitivity was investigated.

Design: Fifty-four persons with HIV and elevated serum triglycerides (>150 mg/dL) and/or abnormal Quantitative Insulin Sensitivity Check Index values (<0.35 but >0.30) were recruited for a dietary intervention in which total fat, type of fat, fiber, and glycemic load were controlled along with supplementation with n–3 fatty acids to achieve an intake of 6 g/d. The subjects were randomly assigned to an intervention or control group, and serum lipids, markers of insulin sensitivity, and serum phospholipid fatty acids were measured in both groups at baseline, 3 wk, and 13 wk.

Results: Triglycerides in the intervention group decreased from a median of 180 mg/dL (interquartile range: 141, 396) to 114 mg/dL (interquartile range: 84, 169) from baseline to 3 wk, whereas they remained stable in the control group (P = 0.003). Serum phospholipid fatty acids indicated a decrease in de novo lipogenesis and a decrease in arachidonic acid (% nmol; P ≤ 0.001) in the intervention group. At 3 wk, the insulin area under the curve decreased but not significantly.

Conclusions: Diet and n–3 fatty acid supplementation dramatically reduced serum triglycerides, decreased arachidonic acid in the phospholipids fraction, and appeared to decrease the de novo lipogenesis associated with the metabolic syndrome in the intervention group.

Short-term sleep loss decreases physical activity under free-living conditions but does not increase food intake under time-deprived laboratory conditions in healthy men

Short-term sleep loss decreases physical activity under free-living conditions but does not increase food intake under time-deprived laboratory conditions in healthy men [Obesity and eating disorders]

from American Journal of Clinical Nutrition current issue by Schmid, S. M, Hallschmid, M., Jauch-Chara, K., Wilms, B., Benedict, C., Lehnert, H., Born, J., Schultes, B.

Background: Short sleep duration is correlated with an increased risk of developing obesity and cardiovascular disease, but the mechanisms behind this relation are largely unknown.

Objective: We aimed to test the hypothesis that acute sleep loss decreases physical activity while increasing food intake, thereby shifting 2 crucial behavioral components of energy homeostasis toward weight gain.

Design: In 15 healthy, normal-weight men, spontaneous physical activity was registered by accelerometry during the entire experiment, and food intake as well as relevant hormones were assessed during a 15-h daytime period after 2 nights of regular sleep (bed time: 2245–0700) and after 2 nights of restricted sleep (bed time: 0245–0700). Experiments were performed in a crossover design.

Results: Sleep restriction significantly decreased physical activity during the daytime spent under free-living conditions after the first night of sleep manipulation (P = 0.008). Also, intensities of physical activity were shifted toward lower levels, with less time spent with intense activities (P = 0.046). Total energy intake, feelings of hunger, and appetite as well as ghrelin and leptin concentrations during day 2 remained unaffected by acute sleep restriction.

Conclusions: In contrast to our expectation, short-term sleep loss neither increased food intake nor affected concentrations of the hunger-regulating hormones leptin and ghrelin. However, the observed decrease in daytime physical activity may point to another potentially important behavioral mechanism for the health-impairing influence of sleep loss.

Increased food energy supply is more than sufficient to explain the US epidemic of obesity

Increased food energy supply is more than sufficient to explain the US epidemic of obesity

from American Journal of Clinical Nutrition current issue by Swinburn, B., Sacks, G., Ravussin, E.

Background: The major drivers of the obesity epidemic are much debated and have considerable policy importance for the population-wide prevention of obesity.

Objective: The objective was to determine the relative contributions of increased energy intake and reduced physical activity to the US obesity epidemic.

Design: We predicted the changes in weight from the changes in estimated energy intakes in US children and adults between the 1970s and 2000s. The increased US food energy supply (adjusted for wastage and assumed to be proportional to energy intake) was apportioned to children and adults and inserted into equations that relate energy intake to body weight derived from doubly labeled water studies. The weight increases predicted from the equations were compared with weight increases measured in representative US surveys over the same period.

Results: For children, the measured weight gain was 4.0 kg, and the predicted weight gain for the increased energy intake was identical at 4.0 kg. For adults, the measured weight gain was 8.6 kg, whereas the predicted weight gain was somewhat higher (10.8 kg).

Conclusions: Increased energy intake appears to be more than sufficient to explain weight gain in the US population. A reversal of the increase in energy intake of 2000 kJ/d (500 kcal/d) for adults and of 1500 kJ/d (350 kcal/d) for children would be needed for a reversal to the mean body weights of the 1970s. Alternatively, large compensatory increases in physical activity (eg, 110–150 min of walking/d), or a combination of both, would achieve the same outcome. Population approaches to reducing obesity should emphasize a reduction in the drivers of increased energy intake.

Green tea, black tea, and epigallocatechin modify body composition, improve glucose tolerance, and differentially alter metabolic gene expression in rats fed a high-fat diet

Green tea, black tea, and epigallocatechin modify body composition, improve glucose tolerance, and differentially alter metabolic gene expression in rats fed a high-fat diet

from Nutrition Research
by Nora Chen, Rebecca Bezzina, Edward Hinch, Paul A. Lewandowski, David Cameron-Smith, Michael L. Mathai, Markandeya Jois, Andrew J. Sinclair, Denovan P. Begg, John D. Wark, Harrison S. Weisinger, Richard S. Weisinger

Abstract: The mechanisms of how tea and epigallocatechin-3-gallate (EGCG) lower body fat are not completely understood. This study investigated long-term administration of green tea (GT), black tea (BT), or isolated EGCG (1 mg/kg per day) on body composition, glucose tolerance, and gene expression related to energy metabolism and lipid homeostasis; it was hypothesized that all treatments would improve the indicators of metabolic syndrome. Rats were fed a 15% fat diet for 6 months from 4 weeks of age and were supplied GT, BT, EGCG, or water. GT and BT reduced body fat, whereas GT and EGCG increased lean mass. At 16 weeks GT, BT, and EGCG improved glucose tolerance. In the liver, GT and BT increased the expression of genes involved in fatty acid synthesis (SREBP-1c, FAS, MCD, ACC) and oxidation (PPAR-α, CPT-1, ACO); however, EGCG had no effect. In perirenal fat, genes that mediate adipocyte differentiation were suppressed by GT (Pref-1, C/EBP-β, and PPAR-γ) and BT (C/EBP-β), while decreasing LPL, HSL, and UCP-2 expression; EGCG increased expression of UCP-2 and PPAR-γ genes. Liver triacylglycerol content was unchanged. The results suggest that GT and BT suppressed adipocyte differentiation and fatty acid uptake into adipose tissue, while increasing fat synthesis and oxidation by the liver, without inducing hepatic fat accumulation. In contrast, EGCG increased markers of thermogenesis and differentiation in adipose tissue, while having no effect on liver or muscle tissues at this dose. These results show novel and separate mechanisms by which tea and EGCG may improve glucose tolerance and support a role for these compounds in obesity prevention.

Perceived Stress and Weight Gain in Adolescence: A Longitudinal Analysis

Perceived Stress and Weight Gain in Adolescence: A Longitudinal Analysis

Cornelia H.M. van Jaarsveld1, Jennifer A. Fidler1, Andrew Steptoe2, David Boniface1 and Jane Wardle1
1Health Behaviour Research Centre, Department of Epidemiology and Public Health, University College London, London, UK
2Psychobiology Group, Department of Epidemiology and Public Health, University College London, London, UK

Abstract

Although perceived stress has been hypothesized to be a risk factor for obesity, epidemiological studies relating stress to weight gain have shown mixed results. We examined prospective associations between perceived stress and changes in waist circumference and BMI in a large study of adolescents. As part of the Health and Behaviour in Teenagers Study (HABITS), height, weight, and waist circumference were measured annually in 4,065 adolescents aged from 11 to 16. Waist and BMI standard deviation scores (SDS) were used as indices of adiposity. Adolescents completed a measure of perceived stress each year, from which mean stress scores over the 5-year period were also calculated and divided by tertile into lower, moderate, and higher stress. Associations between perceived stress at each year and adiposity 1–4 years later and also adiposity trajectories over the whole period in relation to mean stress were investigated. Analyses were adjusted for age, sex, ethnicity, socioeconomic deprivation, pubertal timing, and smoking. Perceived stress in any year was not related prospectively to increases in waist or BMI SDS 1–4 years later, nor was there any evidence that higher stress over the whole period was associated with greater gains in waist or BMI SDS. However, waist and BMI SDS were significantly higher in the moderate- and higher-stress groups than the lower-stress group across the whole 5-year period. Persistent stress was associated with higher waist circumference and BMI in adolescence, but did not lead to differential changes over 5 years.

Antiobesity Effects of yerba maté Extract (Ilex paraguariensis) in High-fat Diet–induced Obese Mice

Antiobesity Effects of yerba maté Extract (Ilex paraguariensis) in High-fat Diet–induced Obese Mice

Demétrius P. Arçari1,2, Waldemar Bartchewsky1, Tanila W. dos Santos1, Karim A. Oliveira1, Alexandre Funck1, José Pedrazzoli1, Marina F.F. de Souza2, Mario J. Saad3, Deborah H.M. Bastos2, Alessandra Gambero1, Patricia de O. Carvalho4 and Marcelo L. Ribeiro1
1Unidade Integrada de Farmacologia e Gastroenterologia, Universidade São Francisco, Bragança Paulista, Brazil
2Departamento de Nutrição, Faculdade de Saúde Publica, Universidade de São Paulo, São Paulo, Brazil
3Departamento de Medicina Interna UNICAMP, Campinas, Brazil
4Laboratório Multidisciplinar de Pesquisa, Universidade São Francisco, Bragança Paulista, Brazil

Abstract

Because the potential of yerba maté (Ilex paraguariensis) has been suggested in the management of obesity, the aim of the present study was to evaluate the effects of yerba maté extract on weight loss, obesity-related biochemical parameters, and the regulation of adipose tissue gene expression in high-fat diet–induced obesity in mice. Thirty animals were randomly assigned to three groups. The mice were introduced to standard or high-fat diets. After 12 weeks on a high-fat diet, mice were randomly assigned according to the treatment (water or yerba maté extract 1.0 g/kg). After treatment intervention, plasma concentrations of total cholesterol, high-density lipoprotein cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, and glucose were evaluated. Adipose tissue was examined to determine the mRNA levels of several genes such as tumor necrosis factor- (TNF-), leptin, interleukin-6 (IL-6), C-C motif chemokine ligand-2 (CCL2), CCL receptor-2 (CCR2), angiotensinogen, plasminogen activator inhibitor-1 (PAI-1), adiponectin, resistin, peroxisome proliferator-activated receptor-2 (PPAR-2), uncoupling protein-1 (UCP1), and PPAR- coactivator-1 (PGC-1). The F4/80 levels were determined by immunoblotting. We found that obese mice treated with yerba maté exhibited marked attenuation of weight gain, adiposity, a decrease in epididymal fat-pad weight, and restoration of the serum levels of cholesterol, triglycerides, LDL cholesterol, and glucose. The gene and protein expression levels were directly regulated by the high-fat diet. After treatment with yerba maté extract, we observed a recovery of the expression levels. In conclusion, our data show that yerba maté extract has potent antiobesity activity in vivo. Additionally, we observed that the treatment had a modulatory effect on the expression of several genes related to obesity.

A Meta-Analysis Evaluating the Impact of Chitosan on Serum Lipids in Hypercholesterolemic Patients

A Meta-Analysis Evaluating the Impact of Chitosan on Serum Lipids in Hypercholesterolemic Patients

William L. Bakera, c, Alix Terciusb, Moise Angladeb, C. Michael Whitea, c, Craig I. Colemana, c

University of Connecticut Schools of
aPharmacy and
bMedicine, Storrs, Conn. and Farmington, Conn., and
cEvidence-Based Practice Center at Hartford Hospital, Hartford, Conn., USA

Address of Corresponding Author

Ann Nutr Metab 2009;55:368-374 (DOI: 10.1159/000258633)

Key Words
Chitin
Chitosan
Hypercholesterolemia
Meta-analysis

Abstract

Background/Objective: Chitosan is increasingly being used in the United States as an over-the-counter cholesterol-lowering agent. The positively charged amino groups of chitosan may have the ability to bind negatively charged molecules such as lipids and bile acids, inducing a greater fractional excretion in the feces. To better characterize the impact of chitosan on serum lipids in hypercholesterolemic patients, we performed a meta-analysis of randomized controlled trials. Methods: A systematic literature search of Medline, Embase, Cochrane Central and the Natural Medicines Comprehensive Database was conducted from the earliest possible date through May 2008. Trials were included in the analysis if they were randomized, placebo-controlled trials of chitosan in hypercholesterolemic patients and reported efficacy data on total, low-density lipoprotein (LDL), high-density lipoprotein (HDL) cholesterol or triglycerides. The weighted mean difference (WMD) of the change from baseline (in milligrams per deciliter) with 95% confidence interval was calculated as the difference between the mean in the chitosan and placebo groups using a random-effects model. Results: Six studies (n = 416 patients) met the inclusion criteria. Upon meta-analysis, the use of chitosan significantly lowered total cholesterol [WMD, -11.59 mg/dl (-21.45 to -1.73), p = 0.02] but not LDL cholesterol, HDL cholesterol or triglycerides.

Conclusions: Based upon the currently available literature, we can only say that chitosan beneficially affects total cholesterol with 95% confidence. Additional, larger randomized controlled trials are needed to better characterize the effect of chitosan on other lipoproteins.

Sustained participation in youth sport decreases metabolic syndrome in adulthood

Sustained participation in youth sport decreases metabolic syndrome in adulthood

X Yang1, R Telama2, M Hirvensalo2, J S A Viikari3 and O T Raitakari4
1LIKES Research Center for Sport and Health Sciences, Jyväskylä, Finland
2Department of Sport Sciences, University of Jyväskylä, Jyväskylä, Finland
3Department of Medicine, University of Turku, Turku, Finland
4Department of Clinical Physiology, University of Turku, Turku, Finland

Correspondence: Dr X Yang, LIKES Research Center for Sport and Health Sciences, Yliopistonkatu 20, Jyväskylä 40100, Finland. E-mail: xiaolin.yang@likes.fi

Received 13 May 2009; Revised 18 June 2009; Accepted 28 June 2009; Published online 1 September 2009.

Abstract
Objective: to explore the effect of organized youth sport on metabolic syndrome (MetS) in adulthood.
Design: Longitudinal study data from the cardiovascular risk in young Finns study.
Subjects: A total of 1493 males (n=704) and females (n=789) aged 3, 6, 9, 12, 15 and 18 years were randomly selected from five university towns and their rural surroundings in 1980. They were followed up for 21 years. In 2001 they were 24, 27, 30, 33, 36 and 39 years old.
Measurements: Youth sports participation data (participation in sport-club training and competitions) were assessed in 1980 and 1983 using a self-report questionnaire completed in connection with a medical examination. Participants were divided into athletes and non-athletes at each measurement point, and then classified into four groups: Persistent athlete, Starter, Leaver and Non-athlete. A mean score of youth sport was assessed by calculating the average of four consecutive measurements (1980–1989). MetS risk in 2001 was defined as a categorical variable based on the guidelines of the European Group for the Study of Insulin Resistance (EGIR) and as a continuous MetS-score variable by summing the z-scores of individual metabolic variables.
Results: In males and females, intense participation in youth sports over 3 years was inversely and significantly associated with clustered MetS score and prevalence of MetS defined by EGIR in adulthood (P<0.05). The association remained significant after adjustment for age, baseline clustered MetS score, smoking and total caloric intake and after additional adjustments for adult leisure-time physical activity. Starters during 3 years were less likely to have MetS than non-athletes. Leavers were at a higher risk for MetS than persistent athletes. These associations were attenuated in males by adjustment for all potential confounders. Similar associations were found using EGIR MetS as an outcome.
Conclusions: Sustained participation in organized sport lasting at least 3 years in youth is associated with reduced risk for developing MetS in adulthood.

Alcohol as a Risk Factor for Type 2 Diabetes: A systematic review and meta-analysis

Alcohol as a Risk Factor for Type 2 Diabetes: A systematic review and meta-analysis

by Baliunas, D. O., Taylor, B. J., Irving, H., Roerecke, M., Patra, J., Mohapatra, S., Rehm, J.

OBJECTIVE 

To clarify the dose-response relationship between alcohol consumption and type 2 diabetes.

RESEARCH DESIGN AND METHODS 

A systematic computer-assisted and hand search was conducted to identify relevant articles with longitudinal design and quantitative measurement of alcohol consumption. Adjustment was made for the sick-quitter effect. We used fractional polynomials in a meta-regression to determine the dose-response relationships by sex and end point using lifetime abstainers as the reference group.

RESULTS 

The search revealed 20 cohort studies that met our inclusion criteria. A U-shaped relationship was found for both sexes. Compared with lifetime abstainers, the relative risk (RR) for type 2 diabetes among men was most protective when consuming 22 g/day alcohol (RR 0.87 [95% CI 0.76–1.00]) and became deleterious at just over 60 g/day alcohol (1.01 [0.71–1.44]). Among women, consumption of 24 g/day alcohol was most protective (0.60 [0.52–0.69]) and became deleterious at about 50 g/day alcohol (1.02 [0.83–1.26]).

CONCLUSIONS 

Our analysis confirms previous research findings that moderate alcohol consumption is protective for type 2 diabetes in men and women.

Sleep Duration, Lifestyle Intervention, and Incidence of Type 2 Diabetes in Impaired Glucose Tolerance: The Finnish Diabetes Prevention Study

Sleep Duration, Lifestyle Intervention, and Incidence of Type 2 Diabetes in Impaired Glucose Tolerance: The Finnish Diabetes Prevention Study

by Tuomilehto, H., Peltonen, M., Partinen, M., Lavigne, G., Eriksson, J. G., Herder, C., Aunola, S., Keinanen-Kiukaanniemi, S., Ilanne-Parikka, P., Uusitupa, M., Tuomilehto, J., Lindstrom, J., on behalf of the Finnish Diabetes Prevention Study Group

OBJECTIVE 

Both short and long sleep duration have frequently been found to be associated with an increased risk for diabetes. The aim of the present exploratory analysis was to examine the association between sleep duration and type 2 diabetes after lifestyle intervention in overweight individuals with impaired glucose tolerance in a 7-year prospective follow-up.

RESEARCH DESIGN AND METHODS 

A total of 522 individuals (aged 40–64 years) were randomly allocated either to an intensive diet-exercise counseling group or to a control group. Diabetes incidence during follow-up was calculated according to sleep duration at baseline. Sleep duration was obtained for a 24-h period. Physical activity, dietary intakes, body weight, and immune mediators (C-reactive protein and interleukin-6) were measured.

RESULTS 

Interaction between sleep duration and treatment group was statistically significant (P = 0.003). In the control group, the adjusted hazard ratios (HRs) (95% CI) for diabetes were 2.29 (1.38–3.80) and 2.74 (1.67–4.50) in the sleep duration groups 9–9.5 h and ?10 h, respectively, compared with for that of the 7–8.5 h group. In contrast, sleep duration did not influence the incidence of diabetes in the intervention group; for sleep duration groups 9–9.5 h and ?10 h, the adjusted HRs (95% CI) were 1.10 (0.60–2.01) and 0.73 (0.34–1.56), respectively, compared with that in the reference group (7–8.5 h sleep). Lifestyle intervention resulted in similar improvement in body weight, insulin sensitivity, and immune mediator levels regardless of sleep duration.

CONCLUSIONS 

Long sleep duration is associated with increased type 2 diabetes risk. Lifestyle intervention with the aim of weight reduction, healthy diet, and increased physical activity may ameliorate some of this excess risk.

Eat less and exercise more - is it really enough to knock down the obesity pandemia?

Eat less and exercise more - is it really enough to knock down the obesity pandemia?

Hubácek JA.

Institute for Clinical and Experimental Medicine-CEM-LMG, Prague, Czech Republic. jahb@ikem.cz.

Reduced physical activity and abundant energy intake are two most common factors leading to uncontrolled body weight gain. But these factors are not under entire internal consciousness control; they are also partially genetically determined and are affected by for example food marketing practices. In addition to these two widely accepted factors, there are some other factors, whose could also contribute to the recent increase of obesity prevalence. For example, non-exercise activity thermogenesis, sleeping habits, more stable inside room temperatures (using of heating and air conditioning), high prescription of medications with weight gain as side effect, psychosocial factors, unfavourable socioeconomic status and unpleasant urban environment are the background factors which should not be omitted if obesity/BMI determination should be fully understood and kept under control. In conclusion, unhealthy life style is necessary, but not sufficient for obesity development.

Viral obesity: fact or fiction?

Viral obesity: fact or fiction?

Mitra AK, Clarke K.

Department of Community Health Sciences, The University of Southern Mississippi, Hattiesburg, MS, USA.

Summary The aetiology of obesity is multifactorial. An understanding of the contributions of various causal factors is essential for the proper management of obesity. Although it is primarily thought of as a condition brought on by lifestyle choices, recent evidence shows there is a link between obesity and viral infections. Numerous animal models have documented an increased body weight and a number of physiologic changes, including increased insulin sensitivity, increased glucose uptake and decreased leptin secretion that contribute to an increase in body fat in adenovirus-36 infection. Other viral agents associated with increasing obesity in animals included canine distemper virus, rous-associated virus 7, scrapie, Borna disease virus, SMAM-1 and other adenoviruses. This review attempted to determine if viral infection is a possible cause of obesity. Also, this paper discussed mechanisms by which viruses might produce obesity. Based on the evidence presented in this paper, it can be concluded that a link between obesity and viral infections cannot be ruled out. Further epidemiologic studies are needed to establish a causal link between the two, and determine if these results can be used in future management and prevention of obesity.

Eating Slowly Increases the Postprandial Response of the Anorexigenic Gut Hormones, Peptide YY and Glucagon-Like Peptide-1.

Eating Slowly Increases the Postprandial Response of the Anorexigenic Gut Hormones, Peptide YY and Glucagon-Like Peptide-1.

Kokkinos A, le Roux CW, Alexiadou K, Tentolouris N, Vincent RP, Kyriaki D, Perrea D, Ghatei MA, Bloom SR, Katsilambros N.

First Department of Propaedeutic Medicine (A.K., K.A., N.T., D.K., D.P., N.K.), Athens University Medical School, Laiko General Hospital, 11527 Athens, Greece; and Department of Metabolic Medicine (C.W.l.R., R.P.V., M.A.G., S.R.B.), Hammersmith Hospital, Imperial College, London W12 ONN, United Kingdom.

Context: The rate at which people eat has been suggested to be positively associated with obesity, although appetite and related gut hormones have not been measured. Objective: The objective of the study was to determine whether eating the same meal at varying speeds elicits different postprandial gut peptide responses. Design and Setting: This was a crossover study at a clinical research facility. Study Participants: Seventeen healthy adult male volunteers participated in the study. Intervention: A test meal consisting of 300 ml ice cream (675 kcal) was consumed in random order on two different sessions by each subject: meal duration took either 5 or 30 min. Main Outcome Measures: The postprandial response of the orexigenic hormone ghrelin and the anorexigenic peptides peptide YY and glucagon-like peptide-1 over 210 min was assessed. Visual analog scales for the subjective feelings of hunger and fullness were completed throughout each session. Results: Peptide YY area under the curve (AUC) was higher after the 30-min meal than after the 5-min meal (mean +/- SEM AUC 5 min meal: 4133 +/- 324, AUC 30 min meal: 5250 +/- 330 pmol/liter . min, P = 0.004), as was glucagon-like peptide-1 AUC (mean +/- SEM AUC 5 min meal: 6219 +/- 256, AUC 30 min meal: 8794 +/- 656 pmol/liter . min, P = 0.001). There was a trend for higher visual analog scale fullness ratings immediately after the end of the 30-min meal compared with immediately after the 5-min meal. There were no differences in ghrelin response. Conclusions: Eating at a physiologically moderate pace leads to a more pronounced anorexigenic gut peptide response than eating very fast.

The energy expenditure of using a "walk-and-work" desk for office workers with obesity.

The energy expenditure of using a "walk-and-work" desk for office workers with obesity.

Levine JA, Miller JM.

Endocrine Research Unit, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA. levine.james@mayo.edu

OBJECTIVE: For many people, most of the working day is spent sitting in front of a computer screen. Approaches for obesity treatment and prevention are being sought to increase workplace physical activity because low levels of physical activity are associated with obesity. Our hypothesis was that a vertical workstation that allows an obese individual to work while walking would be associated with significant and substantial increases in energy expenditure over seated work. METHODS: The vertical workstation is a workstation that allows an office worker to use a standard personal computer while walking on a treadmill at a self-selected velocity. 15 sedentary individuals with obesity (14 women, one man; 43 (7.5) years, 86 (9.6) kg; body mass index 32 (2.6) kg/m(2)) underwent measurements of energy expenditure at rest, seated working in an office chair, standing and while walking at a self-selected speed using the vertical workstation. Body composition was measured using dual x ray absorptiometry. RESULTS: The mean (SD) energy expenditure while seated at work in an office chair was 72 (10) kcal/h, whereas the energy expenditure while walking and working at a self-selected velocity of 1.1 (0.4) mph was 191 (29) kcal/h. The mean (SD) increase in energy expenditure for walking-and-working over sitting was 119 (25) kcal/h. CONCLUSIONS: If sitting computer-time were replaced by walking-and-working, energy expenditure could increase by 100 kcal/h. Thus, if obese individuals were to replace time spent sitting at the computer with walking computer time by 2-3 h/day, and if other components of energy balance were constant, a weight loss of 20-30 kg/year could occur.

Effect of cocoa powder on the modulation of inflammatory biomarkers in patients at high risk of cardiovascular disease

Effect of cocoa powder on the modulation of inflammatory biomarkers in patients at high risk of cardiovascular disease 

[Cardiovascular disease risk]

from American Journal of Clinical Nutrition current issue by Monagas, M., Khan, N., Andres-Lacueva, C., Casas, R., Urpi-Sarda, M., Llorach, R., Lamuela-Raventos, R. M., Estruch, R.

Background: Epidemiologic studies have suggested that flavonoid intake plays a critical role in the prevention of coronary heart disease. Because atherosclerosis is considered a low-grade inflammatory disease, some feeding trials have analyzed the effects of cocoa (an important source of flavonoids) on inflammatory biomarkers, but the results have been controversial.

Objective: The objective was to evaluate the effects of chronic cocoa consumption on cellular and serum biomarkers related to atherosclerosis in high-risk patients.

Design: Forty-two high-risk volunteers (19 men and 23 women; mean ± SD age: 69.7 ± 11.5 y) were included in a randomized crossover feeding trial. All subjects received 40 g cocoa powder with 500 mL skim milk/d (C+M) or only 500 mL skim milk/d (M) for 4 wk. Before and after each intervention period, cellular and serum inflammatory biomarkers related to atherosclerosis were evaluated.

Results: Adherence to the dietary protocol was excellent. No significant changes in the expression of adhesion molecules on T lymphocyte surfaces were found between the C+M and M groups. However, in monocytes, the expression of VLA-4, CD40, and CD36 was significantly lower (P = 0.005, 0.028, and 0.001, respectively) after C+M intake than after M intake. In addition, serum concentrations of the soluble endothelium-derived adhesion molecules P-selectin and intercellular adhesion molecule-1 were significantly lower (both P = 0.007) after C+M intake than after M intake.

Conclusions: These results suggest that the intake of cocoa polyphenols may modulate inflammatory mediators in patients at high risk of cardiovascular disease. These antiinflammatory effects may contribute to the overall benefits of cocoa consumption against atherosclerosis.

Short-term modified alternate-day fasting: a novel dietary strategy for weight loss and cardioprotection in obese adults

Short-term modified alternate-day fasting: a novel dietary strategy for weight loss and cardioprotection in obese adults 

[Obesity and eating disorders]

from American Journal of Clinical Nutrition current issue by Varady, K. A, Bhutani, S., Church, E. C, Klempel, M. C

Background: The ability of modified alternate-day fasting (ADF; ie, consuming 25% of energy needs on the fast day and ad libitum food intake on the following day) to facilitate weight loss and lower vascular disease risk in obese individuals remains unknown.

Objective: This study examined the effects of ADF that is administered under controlled compared with self-implemented conditions on body weight and coronary artery disease (CAD) risk indicators in obese adults.

Design: Sixteen obese subjects (12 women, 4 men) completed a 10-wk trial, which consisted of 3 phases: 1) a 2-wk control phase, 2) a 4-wk weight loss/ADF controlled food intake phase, and 3) a 4-wk weight loss/ADF self-selected food intake phase.

Results: Dietary adherence remained high throughout the controlled food intake phase (days adherent: 86%) and the self-selected food intake phase (days adherent: 89%). The rate of weight loss remained constant during controlled food intake (0.67 ± 0.1 kg/wk) and self-selected food intake phases (0.68 ± 0.1 kg/wk). Body weight decreased (P < 0.001) by 5.6 ± 1.0 kg (5.8 ± 1.1%) after 8 wk of diet. Percentage body fat decreased (P < 0.01) from 45 ± 2% to 42 ± 2%. Total cholesterol, LDL cholesterol, and triacylglycerol concentrations decreased (P < 0.01) by 21 ± 4%, 25 ± 10%, and 32 ± 6%, respectively, after 8 wk of ADF, whereas HDL cholesterol remained unchanged. Systolic blood pressure decreased (P < 0.05) from 124 ± 5 to 116 ± 3 mm Hg.

Conclusion: These findings suggest that ADF is a viable diet option to help obese individuals lose weight and decrease CAD risk. This trial was registered at clinicaltrials.gov as UIC-004-2009.

Circadian Timing of Food Intake Contributes to Weight Gain

Circadian Timing of Food Intake Contributes to Weight Gain

Deanna M. Arble1, Joseph Bass1,2, Aaron D. Laposky1, Martha H. Vitaterna1 and Fred W. Turek1

Abstract

Studies of body weight regulation have focused almost entirely on caloric intake and energy expenditure. However, a number of recent studies in animals linking energy regulation and the circadian clock at the molecular, physiological, and behavioral levels raise the possibility that the timing of food intake itself may play a significant role in weight gain. The present study focused on the role of the circadian phase of food consumption in weight gain. We provide evidence that nocturnal mice fed a high-fat diet only during the 12-h light phase gain significantly more weight than mice fed only during the 12-h dark phase. A better understanding of the role of the circadian system for weight gain could have important implications for developing new therapeutic strategies for combating the obesity epidemic facing the human population today.

A very low carbohydrate ketogenic diet improves glucose tolerance in ob/ob mice independently of weight loss

A very low carbohydrate ketogenic diet improves glucose tolerance in ob/ob mice independently of weight loss

by Badman, M. K., Kennedy, A. R., Adams, A. C., Pissios, P., Maratos-Flier, E.

In mice of normal weight and with diet-induced obesity, a high-fat, low-carbohydrate ketogenic diet (KD) causes weight loss, reduced circulating glucose and lipids, and dramatic changes in hepatic gene expression. Many of the effects of KD are mediated by fibroblast growth factor 21 (FGF21). We tested the effects of KD feeding on ob/ob mice to determine if metabolic effects would occur in obesity secondarily to leptin deficiency. We evaluated the effect of prolonged KD feeding on weight, energy homeostasis, circulating metabolites, glucose homeostasis, and gene expression. Subsequently, we evaluated the effects of leptin and fasting on FGF21 expression in ob/ob mice. KD feeding of ob/ob mice normalized fasting glycemia and substantially reduced insulin and lipid levels in the absence of weight loss. KD feeding was associated with significant increases in lipid oxidative genes and reduced expression of lipid synthetic genes, including stearoyl-coenzyme A desaturase 1, but no change in expression of inflammatory markers. In chow-fed ob/ob mice, FGF21 mRNA was elevated 10-fold compared with wild-type animals, and no increase from this elevated baseline was seen with KD feeding. Administration of leptin to chow-fed ob/ob mice led to a 24-fold induction of FGF21. Fasting also induced hepatic FGF21 in ob/ob mice. Thus, KD feeding improved ob/ob mouse glucose homeostasis without weight loss or altered caloric intake. These data demonstrate that manipulation of dietary macronutrient composition can lead to marked improvements in metabolic profile of leptin-deficient obese mice in the absence of weight loss.

Inflammation and impaired adipogenesis in hypertrophic obesity in man

Inflammation and impaired adipogenesis in hypertrophic obesity in man

by Gustafson, B., Gogg, S., Hedjazifar, S., Jenndahl, L., Hammarstedt, A., Smith, U.

Obesity is associated mainly with adipose cell enlargement in adult man (hypertrophic obesity), whereas the formation of new fat cells (hyperplastic obesity) predominates in the prepubertal age. Adipose cell size, independent of body mass index, is negatively correlated with whole body insulin sensitivity. Here, we review recent findings linking hypertrophic obesity with inflammation and a dysregulated adipose tissue, including local cellular insulin resistance with reduced IRS-1 and GLUT4 protein content. In addition, the number of preadipocytes in the abdominal subcutaneous adipose tissue capable of undergoing differentiation to adipose cells is reduced in hypertrophic obesity. This is likely to promote ectopic lipid accumulation, a well-known finding in these individuals and one that promotes insulin resistance and cardiometabolic risk. We also review recent results showing that TNF, but not MCP-1, resistin, or IL-6, completely prevents normal adipogenesis in preadipocytes, activates Wnt signaling, and induces a macrophage-like phenotype in the preadipocytes. In fact, activated preadipocytes, rather than macrophages, may completely account for the increased release of chemokines and cytokines by the adipose tissue in obesity. Understanding the molecular mechanisms for the impaired preadipocyte differentiation in the subcutaneous adipose tissue in hypertrophic obesity is a priority since it may lead to new ways of treating obesity and its associated metabolic complications.

The origin of intermuscular adipose tissue and its pathophysiological implications

The origin of intermuscular adipose tissue and its pathophysiological implications

by Vettor, R., Milan, G., Franzin, C., Sanna, M., De Coppi, P., Rizzuto, R., Federspil, G.

The intermuscular adipose tissue (IMAT) is a depot of adipocytes located between muscle bundles. Several investigations have recently been carried out to define the phenotype, the functional characteristics, and the origin of the adipocytes present in this depot. Among the different mechanisms that could be responsible for the accumulation of fat in this site, the dysdifferentiation of muscle-derived stem cells or other mesenchymal progenitors has been postulated, turning them into cells with an adipocyte phenotype. In particular, muscle satellite cells (SCs), a heterogeneous stem cell population characterized by plasticity and self-renewal that allow muscular growth and regeneration, can acquire features of adipocytes, including the abilities to express adipocyte-specific genes and accumulate lipids. Failure to express the transcription factors that direct mesenchymal precursors into fully differentiated functionally specialized cells may be responsible for their phenotypic switch into the adipogenic lineage. We proved that human SCs also possess a clear adipogenic potential that could explain the presence of mature adipocytes within skeletal muscle. This occurs under some pathological conditions (i.e., primary myodystrophies, obesity, hyperglycemia, high plasma free fatty acids, hypoxia, etc.) or as a consequence of thiazolidinedione treatment or simply because of a sedentary lifestyle or during aging. Several pathways and factors (PPARs, WNT growth factors, myokines, GEF-GAP-Rho, p66shc, mitochondrial ROS production, PKCß) could be implicated in the adipogenic conversion of SCs. The understanding of the molecular pathways that regulate muscle-to-fat conversion and SC behavior could explain the increase in IMAT depots that characterize many metabolic diseases and age-related sarcopenia.

Transdifferentiation properties of adipocytes in the adipose organ

Transdifferentiation properties of adipocytes in the adipose organ

by Cinti, S.

Mammals have two types of adipocytes, white and brown, but their anatomy and physiology is different. White adipocytes store lipids, and brown adipocytes burn them to produce heat. Previous descriptions implied their localization in distinct sites, but we demonstrated that they are mixed in many depots, raising the concept of adipose organ. We explain the reason for their cohabitation with the hypothesis of reversible physiological transdifferentiation; they are able to convert one into each other. If needed, the brown component of the organ could increase at the expense of the white component and vice versa. This plasticity is important because the brown phenotype of the organ associates with resistance to obesity and related disorders. Another example of physiological transdifferetiation of adipocytes is offered by the mammary gland; the pregnancy hormonal stimuli seems to trigger a reversible transdifferentiation of adipocytes into milk-secreting epithelial glands. The obese adipose organ is infiltrated by macrophages inducing chronic inflamation that is widely considered as a causative factor for insulin resistance. We showed that the vast majority of macrophages infiltrating the obese organ are arranged around dead adipocytes, forming characteristic crown-like structures. We recently found that visceral fat is more infiltrated than the subcutaneous fat despite a smaller size of visceral adipocytes. This suggests a different susceptibility of visceral and subcutaneous adipocytes to death, raising the concept of smaller critical death size that could be important to explain the key role of visceral fat for the metabolic disorders associated with obesity.

Exercise Training and Dietary Glycemic Load May Have Synergistic Effects on Insulin Resistance in Older Obese Adults

Exercise Training and Dietary Glycemic Load May Have Synergistic Effects on Insulin Resistance in Older Obese Adults

John P. Kirwana-d, Hope Barkoukisd, Latina M. Brooksa, b, Christine M. Marchettie, Bradley P. Stetzere, Frank Gonzalezf

  Abstract

Background/Aims: The aim of this study was to assess the combined effects of exercise and dietary glycemic load on insulin resistance in older obese adults. Methods: Eleven men and women (62 ± 2 years; 97.6 ± 4.8 kg; body mass index 33.2 ± 2.0) participated in a 12-week supervised exercise program, 5 days/week, for about 1 h/day, at 80-85% of maximum heart rate. Dietary glycemic load was calculated from dietary intake records. Insulin resistance was determined using the euglycemic (5.0 mM) hyperinsulinemic (40 mU/m2/min) clamp. Results: The intervention improved insulin sensitivity (2.37 ± 0.37 to 3.28 ± 0.52 mg/kg/min, p < 0.004), increased VO2max (p < 0.009), and decreased body weight (p < 0.009). Despite similar caloric intakes (1,816 ± 128 vs. 1,610 ± 100 kcal/day), dietary glycemic load trended towards a decrease during the study (140 ± 10 g before, vs. 115 ± 8 g during, p < 0.04). The change in insulin sensitivity correlated with the change in glycemic load (r = 0.84, p < 0.009). Four subjects reduced their glycemic load by 61 ± 8%, and had significantly greater increases in insulin sensitivity (78 ± 11 vs. 23 ± 8%, p < 0.003), and decreases in body weight (p < 0.004) and plasma triglycerides (p < 0.04) compared to the rest of the group. Conclusion: The data suggest that combining a low-glycemic diet with exercise may provide an alternative and more effective treatment for insulin resistance in older obese adults.

Effects of apple juice on risk factors of lipid profile, inflammation and coagulation, endothelial markers and atherosclerothic lesions in highcholesterolemic rabbits

Effects of apple juice on risk factors of lipid profile, inflammation and coagulation, endothelial markers and atherosclerothic lesions in highcholesterolemic rabbits

by Nafiseh Esmaeil

Background: Atherosclerosis which results from gradual deposition of lipids in medium and large arteries is a leading cause of mortality worldwide. The objective of this study was to determine the effect of apple juice on some risk factors of atherosclerosis and on the development of atherosclerosis in rabbits fed a high-cholesterol diet. Methods: Thirty two male rabbits were randomly divided into four groups: normal diet, high cholesterol diet (%1 cholesterol), 1 % cholesterol supplemented with 5ml apple juice(low dose) and 1 % cholesterol supplemented with 10ml apple juice (high dose) for 2 month. The C-reactive protein (CRP), nitrite, nitrate, fibrinogen,total cholesterol(TC) and factor VII were measured before the experiment and by the end of period. At the end ofstudy, fatty streak formation in right and left coronary arteries were determined using Chekanov method in all groups. Results: Both doses of apple juice significantly were decreased TC, TG, CRP, fibrinogen, factor VII levels, atherosclerotic lesion in right and left coronary arteries and increased nitrite and nitrate compared to cholesterolemic diet.Also using 10ml apple juice caused significant reduce in LDL-C and increase HDL-C , but 5 ml apple juice did not change these factors. Significant differences were observed between 5 and 10ml apple juice groups by LDL-C. No significant difference was found between 5 and 10 ml apple juice groups with regard to CRP, nitrite, nitrate, fibrinogen, factor VII, TG, HDL-C and TC concentrations. Conclusion: Apple juice can effectively prevent the progress of atherosclerosis.This is likely due to antioxidant and anti-inflammatory effect of apple juice.

Short-term effects of replacing milk with cola beverages on insulin-like growth factor-I and insulin-glucose metabolism: a 10 d interventional study in young men.

Short-term effects of replacing milk with cola beverages on insulin-like growth factor-I and insulin-glucose metabolism: a 10 d interventional study in young men.

Hoppe C, Kristensen M, Boiesen M, Kudsk J, Fleischer Michaelsen K, Mølgaard C.

Department of Human Nutrition, University of Copenhagen, Rolighedsvej 30, DK-1958 Fredericksberg, Denmark.

In the Western world, a trend towards increased consumption of carbonated soft drinks combined with a decreasing intake of milk is observed. This may affect circulating insulin-like growth factor I (IGF-I) and fasting insulin, as seen in pre-pubertal children. The present study was designed to reflect the trend of replacing milk with carbonated beverages in young men and to study the effects of this replacement on IGF-I, IGF-binding protein 3 (IGFBP-3), IGF-I:IGFBP-3 and glucose-insulin metabolism. A randomised, controlled crossover intervention study, in which eleven men aged 22-29 years were given a low-Ca diet in two 10 d periods with 10 d washout in between. In one period, they drank 2.5 litres of Coca Cola(R) per day and the other period 2.5 litres of semi-skimmed milk. Serum IGF-I, IGFBP-3 (RIA), insulin (fluoro immunoassay) and glucose (Cobas) were determined at baseline and end point of each intervention period. Insulin resistance and beta-cell function were calculated with the homeostasis model assessment. A decrease in serum IGF-I was observed in the cola period compared with the milk period (P < 0.05). No effects of treatment were observed on IGFBP-3, IGF-I:IGFBP-3, insulin, glucose, insulin resistance or beta-cell function. The present study demonstrates that high intake of cola over a 10 d period decreases total IGF-I compared with a high intake of milk, with no effect on glucose-insulin metabolism in adult men. It is unknown whether this is a transient phenomenon or whether it has long-term consequences.

Effects of a Low Carbohydrate Weight Loss Diet on Exercise Capacity and Tolerance in Obese Subjects

Effects of a Low Carbohydrate Weight Loss Diet on Exercise Capacity and Tolerance in Obese Subjects

Grant D. Brinkworth1, Manny Noakes1, Peter M. Clifton1 and Jonathan D. Buckley2

1Preventative Health Flagship, Commonwealth Scientific and Industrial Research Organisation–Human Nutrition, Adelaide, South Australia, Australia

2Australian Technology Network (ATN) Centre for Metabolic Fitness and Nutritional Physiology Research Centre, University of South Australia, Division of Health Sciences, Adelaide, South Australia, Australia

Correspondence: Grant D. Brinkworth (grant.brinkworth@csiro.au)

Received 11 May 2008; Accepted 8 October 2008; Published online 16 April 2009.

Abstract

Dietary restriction and increased physical activity are recommended for obesity treatment. Very low carbohydrate diets are used to promote weight loss, but their effects on physical function and exercise tolerance in overweight and obese individuals are largely unknown. The aim of this study was to compare the effects of a very low carbohydrate, high fat (LC) diet with a conventional high carbohydrate, low fat (HC) diet on aerobic capacity, fuel utilization during submaximal exercise, perceived exercise effort (RPE) and muscle strength. Sixty subjects (age: 49.2  1.2 years; BMI: 33.6  0.5 kg/m2) were randomly assigned to an energy restricted (~6–7 MJ, 30% deficit), planned isocaloric LC or HC for 8 weeks. At baseline and week 8, subjects performed incremental treadmill exercise to exhaustion and handgrip and isometric knee extensor strength were assessed. Weight loss was greater in LC compared with HC (8.4  0.4% and 6.7  0.5%, respectively; P = 0.01 time  diet). Peak oxygen uptake and heart rate were unchanged in both groups (P > 0.17). Fat oxidation increased during submaximal exercise in LC but not HC (P < 0.001 time diet effect). On both diets, perception of effort during submaximal exercise and handgrip strength decreased (P  0.03 for time), but knee extensor strength remained unchanged (P > 0.25). An LC weight loss diet shifted fuel utilization toward greater fat oxidation during exercise, but had no detrimental effect on maximal or submaximal markers of aerobic exercise performance or muscle strength compared with an HC diet. Further studies are required to determine the interaction of LC diets with regular exercise training and the long-term health effects.

Diet Quality Is Associated with Better Cognitive Test Performance among Aging Men and Women

Diet Quality Is Associated with Better Cognitive Test Performance among Aging Men and Women [Nutritional Epidemiology]

from Journal of Nutrition current issue by Wengreen, H. J., Neilson, C., Munger, R., Corcoran, C.

Most studies of association between diet and cognition among the elderly focus on the role of single nutrients or foods and ignore the complexity of dietary patterns and total diet quality. We prospectively examined associations between an index of diet quality and cognitive function and decline among elderly men and women of the Cache County Study on Memory and Aging in Utah. In 1995, 3634 resident men and women ?65 y of age completed a baseline survey that included a 142-item FFQ. Cognition was assessed using an adapted version of the Modified Mini-Mental State Examination (3MS) at baseline and 3 subsequent interviews spanning ~11 y. A recommended food score (RFS) and non-RFS were computed by summing the number of recommended foods (n = 57) and nonrecommended foods (n = 23) regularly consumed. Multivariable-mixed models were used to estimate associations between the RFS and non-RFS and average 3MS score over time. Those in the highest quartile of RFS scored 1.80 points higher on the baseline 3MS test than did those in the lowest quartile of RFS (P < 0.001). This effect was strengthened over 11 y of follow-up. Those with the highest RFS declined by 3.41 points over 11 y compared with the 5.2-point decline experienced by those with the lowest RFS (P = 0.0013). The non-RFS was not associated with cognitive scores. Consuming a diverse diet that includes a variety of recommended foods may help to attenuate age-related cognitive decline among the elderly.

Choline in anxiety and depression: the Hordaland Health Study

Choline in anxiety and depression: the Hordaland Health Study [Nutritional epidemiology and public health]

from American Journal of Clinical Nutrition current issue by Bjelland, I., Tell, G. S, Vollset, S. E, Konstantinova, S., Ueland, P. M

Background: Despite its importance in the central nervous system as a precursor for acetylcholine and membrane phosphatidylcholine, the role of choline in mental illness has been little studied.

Objective: We examined the cross-sectional association between plasma choline concentrations and scores of anxiety and depression symptoms in a general population sample.

Design: We studied a subsample (n = 5918) of the Hordaland Health Study, including both sexes and 2 age groups of 46–49 and 70–74 y who had valid information on plasma choline concentrations and symptoms of anxiety and depression measured by the Hospital Anxiety and Depression Scale—the latter 2 as continuous measures and dichotomized at a score ?8 for both subscales.

Results: The lowest choline quintile was significantly associated with high anxiety levels (odds ratio: 1.33; 95% CI: 1.06, 1.69) in the fully adjusted (age group, sex, time since last meal, educational level, and smoking habits) logistic regression model. Also, the trend test in the anxiety model was significant (P = 0.007). In the equivalent fully adjusted linear regression model, a significant inverse association was found between choline quintiles and anxiety levels (standardized regression coefficient = –0.027, P = 0.045). We found no significant associations in the corresponding analyses of the relation between plasma choline and depression symptoms.

Conclusion: In this large population–based study, choline concentrations were negatively associated with anxiety symptoms but not with depression symptoms.

Fish consumption during pregnancy, prenatal mercury exposure, and anthropometric measures at birth in a prospective mother-infant cohort study in Spain

Fish consumption during pregnancy, prenatal mercury exposure, and anthropometric measures at birth in a prospective mother-infant cohort study in Spain [Pregnancy and lactation]

from American Journal of Clinical Nutrition current issue by Ramon, R., Ballester, F., Aguinagalde, X., Amurrio, A., Vioque, J., Lacasana, M., Rebagliato, M., Murcia, M., Iniguez, C.

Background: Birth size has been shown to be related to maternal fish intake, although the results are inconsistent.

Objective: The objective was to assess the association of consumption of different types of fish and prenatal mercury exposure with birth weight, birth length, and classification as small for gestational age (SGA) in newborns.

Design: Cord blood total mercury was measured in 554 newborns in a population-based cohort born from 2004 to 2006. Fish consumption was classified in 4 frequency categories (<1 portion/mo, 1–3 portions/mo, 1 portion/wk, and ?2 portions/wk).

Results: When multivariate models were adjusted, newborns in the higher quartile of total mercury weighed 143.7 g less (95% CI: –251.8, –35.6; P for trend = 0.02) and had higher odds of being SGA for length (odds ratio: 5.3; 95% CI: 1.2, 23.9; P from likelihood ratio test = 0.03) without a linear relation (P for trend = 0.13) compared with those in the lowest quartile. Mothers consuming ?2 portions/wk of canned tuna had newborns who weighed more than those who consumed <1 portion/mo (P for trend = 0.03) and a lower risk of having infants who were SGA for weight (P for trend = 0.01). Consumption of ?2 portions/wk of large oily fish was associated with a higher risk of being SGA for weight and consumption of lean fish with a lower risk of being SGA for length compared with the consumption of <1 portion/mo, but in neither case was there a linear relation (P for trend >0.05).

Conclusions: The role of fish in fetal growth depends on the amount and type of fish consumed. The findings for mercury warrant further investigation in other settings.

Application of the Dietary Reference Intakes in developing a recommendation for pregnancy iron supplements in Canada

Application of the Dietary Reference Intakes in developing a recommendation for pregnancy iron supplements in Canada [Vitamins, minerals, and phytochemicals]

from American Journal of Clinical Nutrition current issue by Cockell, K. A, Miller, D. C, Lowell, H.

Background: For many pregnant Canadian women, usual iron intakes from food appear to be inadequate compared with Dietary Reference Intake requirement estimates.

Objective: Dietary intake modeling was undertaken to determine an amount of iron supplementation that would confer acceptably low prevalence of apparently inadequate and apparently excessive intakes.

Design: The distribution of usual dietary iron intakes was estimated with the use of 24-h recalls from pregnant women aged 19–50 y in the Canadian Community Health Survey, Cycle 2.2. The prevalence of usual intakes below the Estimated Average Requirement for pregnancy (22 mg/d) or above the Tolerable Upper Intake Level (45 mg/d) was estimated. Iterative modeling with incremental iron supplement was performed to determine a suitable supplement amount. Because the sample of pregnant women was small (148 day 1 recalls), estimates of the tails of the distributions had large SDs, and supporting analyses based on intake data from nonpregnant women (4540 day 1 recalls) were made.

Results: Daily supplementation shifted the intake distribution curve without changing its shape. Supplementation with 16 mg iron/d was consistent with low (<3%) prevalence of apparently inadequate intakes. This amount of supplementation should not be associated with an increase in apparently excessive intakes by pregnant women in this population.

Conclusions: On the basis of Dietary Reference Intakes, an iron supplement of 16 mg/d throughout pregnancy is justified as both efficacious and safe for healthy women living in Canadian households. This does not preclude the need for therapeutic iron doses for some individuals on the basis of iron status. The method can be applied to other populations if suitable baseline iron intake data are available.

Contribution of individual organ mass loss to weight loss-associated decline in resting energy expenditure

Contribution of individual organ mass loss to weight loss-associated decline in resting energy expenditure [Energy and protein metabolism]

from American Journal of Clinical Nutrition current issue by Bosy-Westphal, A., Kossel, E., Goele, K., Later, W., Hitze, B., Settler, U., Heller, M., Gluer, C.-C., Heymsfield, S. B, Muller, M. J

Background: Weight loss leads to reduced resting energy expenditure (REE) independent of fat-free mass (FFM) and fat mass (FM) loss, but the effect of changes in FFM composition is unclear.

Objective: We hypothesized that a decrease in REE adjusted for FFM with weight loss would be partly explained by a disproportionate loss in the high metabolic activity component of FFM.

Design: Forty-five overweight and obese women [body mass index (in kg/m2): 28.7–46.8] aged 22–46 y followed a low-calorie diet for 12.7 ± 2.2 wk. Body composition was measured by magnetic resonance imaging, dual-energy X-ray absorptiometry, and a 4-compartment model. REE measured by indirect calorimetry (REEm) was compared with REE calculated from detailed body-composition analysis (REEc) by using specific organ metabolic rates (ie, organ REE/mass).

Results: Weight loss was 9.5 ± 3.4 kg (8.0 ± 2.9 kg FM and 1.5 ± 3.1 kg FFM). Decreases in REE (–8%), free triiodothyronine concentrations (–8%), muscle (–3%), heart (–5%), liver (–4%), and kidney mass (–6%) were observed (all P < 0.05). Relative loss in organ mass was significantly higher (P < 0.01) than was the change in low metabolically active FFM components (muscle, bone, and residual mass). After weight loss, REEm – REEc decreased from 0.24 ± 0.58 to 0.01 ± 0.44 MJ/d (P = 0.01) and correlated with the decrease in free triiodothyronine concentrations (r = 0.33, P < 0.05). Women with high adaptive thermogenesis (defined as REEm – REEc < –0.17 MJ/d) had less weight loss and conserved FFM, liver, and kidney mass.

Conclusions: After weight loss, almost 50% of the decrease in REEm was explained by losses in FFM and FM. The variability in REEm explained by body composition increased to 60% by also considering the weight of individual organs.

Effect of vegetarian diets on bone mineral density: a Bayesian meta-analysis

Effect of vegetarian diets on bone mineral density: a Bayesian meta-analysis [Nutritional status, dietary intake, and body composition]

from American Journal of Clinical Nutrition current issue by Ho-Pham, L. T, Nguyen, N. D, Nguyen, T. V

Background: The association between vegetarian diets and bone mineral density (BMD) is controversial because of conflicting findings from previous studies.

Objective: The aim of this study was to estimate the effect of vegetarian diets on BMD by using a meta-analytic approach.

Design: A systematic electronic literature search was conducted to identify all relevant articles on the association between vegetarian diet and BMD. Nine studies of 2749 subjects (1880 women and 869 men) were included in the analysis. Traditional and Bayesian methods of meta-analysis were applied to synthesize the data.

Results: Overall, BMD was 4% lower in vegetarians than in omnivores (95% CI: 2%, 7%) at both the femoral neck and the lumbar spine. Compared with omnivores, vegans had a significantly lower lumbar spine BMD (6% lower; 95% CI: 2%, 9%), which was more pronounced than in lactoovovegetarians (2% lower; 95% CI: 1%, 4%). The probability that BMD was ?5% lower in vegetarians than in omnivores (or 0.3 SD) was 42% for the femoral neck and 32% for the lumbar spine. There was no evidence of publication bias. There was a moderate degree of between-study heterogeneity; the coefficient of heterogeneity varied between 46% and 51%.

Conclusion: The results suggest that vegetarian diets, particularly vegan diets, are associated with lower BMD, but the magnitude of the association is clinically insignificant.

Beverage intake of girls at age 5 y predicts adiposity and weight status in childhood and adolescence

Beverage intake of girls at age 5 y predicts adiposity and weight status in childhood and adolescence [Obesity and eating disorders]

from American Journal of Clinical Nutrition current issue by Fiorito, L. M, Marini, M., Francis, L. A, Smiciklas-Wright, H., Birch, L. L

Background: Increased consumption of sweetened beverage has been linked to higher energy intake and adiposity in childhood.

Objective: The objective was to assess whether beverage intake at age 5 y predicted energy intake, adiposity, and weight status across childhood and adolescence.

Design: Participants were part of a longitudinal study of non-Hispanic white girls and their parents (n = 170) who were assessed biennially from age 5 to 15 y. At each assessment, beverage intake (milk, fruit juice, and sweetened beverages) and energy intake were assessed by using three 24-h recalls. Percentage body fat and waist circumference were measured. Height and weight were measured and used to calculate body mass index. Multiple regression analyses were used to predict the girls' adiposity. In addition, at age 5 y, girls were categorized as consuming <1, ?1 and <2, or ?2 servings of sweetened beverages. A mixed modeling approach was used to assess longitudinal differences and patterns of change in sweetened beverage and energy intake, adiposity, and weight status by frequency of sweetened beverage intake.

Results: Sweetened beverage intake at age 5 y, but not milk or fruit juice intake, was positively associated with adiposity from age 5 to 15 y. Greater consumption of sweetened beverages at age 5 y (?2 servings/d) was associated with a higher percentage body fat, waist circumference, and weight status from age 5 to 15 y.

Conclusion: These findings provide new longitudinal evidence that early intake of sweetened beverages predicts adiposity and weight status across childhood and adolescence.

Effect of exercise on lipolysis in adipose tissue

Effect of exercise on lipolysis in adipose tissue

Jan Polak†, Magda Bajzova & Vladimir Stich

Adipose tissue is a major source of nonesterified fatty acids, which are involved in the etiopathogenesis of several metabolic diseases. Mechanisms regulating the processes of lipolysis are of major importance because they represent potential drug targets. Physical exercise is a cost-effective prevention strategy and important therapy for civilization diseases and is an important physiological stimulus of lipolysis in adipose tissue. Besides the traditional role of catecholamines in the regulation of lipolysis, other recently described lipolytic factors, for example, atrial natriuretic peptide and IL-6, are discussed in the context of lipolysis. In vitro as well as in vivo studies provide a substantial amount of data, which are sometimes contradictory. Exercise modifies the functional balance between β and α adrenergic receptors, increases atrial natriuretic peptide-induced lipolysis and improves sensitivity of adipose tissue to insulin. Actual lipolytic rate is the summary of these complex interactions.

Differential effects of casein versus whey on fasting plasma levels of insulin, IGF-1 and IGF-1/IGFBP-3: results from a randomized 7-day supplementation study in prepubertal boys.

Differential effects of casein versus whey on fasting plasma levels of insulin, IGF-1 and IGF-1/IGFBP-3: results from a randomized 7-day supplementation study in prepubertal boys.

Hoppe, C 1,2; Molgaard, C 1; Dalum, C 1; Vaag, A 3; Michaelsen, K F 1

AB Background/Objectives: Milk increases both fasting insulin and insulin-like growth factor 1 (IGF-1), and thereby growth, in healthy prepubertal boys. It is, however, unknown which components in milk are responsible for milk's growth-stimulating effect. 

Subjects/Methods: To get closer to the identification of which components in milk that stimulate growth, we have performed an intervention study with 57 eight-year-old boys in which we examined the effects of the two major milk protein fractions, whey and casein, and milk minerals (Ca and P) in a 2 x 2 factorial design on IGFs and glucose-insulin metabolism. The amounts of whey and casein were identical to the content in 1.5 l skim milk. The amounts of Ca and P were similar to 1.5 l skim milk in the high-mineral drinks, whereas the amounts of Ca and P were reduced in the low-mineral drinks. 

Results: There were no interactions between milk mineral groups (high, low) and milk protein groups (whey, casein). Serum IGF-1 increased by 15% (P<0.0001), whereas there was no change in fasting insulin (P=0.36) in the casein group. In the whey group, fasting insulin increased by 21% (P=0.006), with no change in IGF-1 (P=0.27). There were no independent effects of a high milk mineral intake on IGF-1 and insulin. 

Conclusions: The main milk protein fractions exhibit important but different growth-promoting effects by increasing either fasting insulin (whey) or IGF-1 (casein) levels.

Phosphate decreases urine calcium and increases calcium balance: A meta-analysis of the osteoporosis acid-ash diet hypothesis

Phosphate decreases urine calcium and increases calcium balance: A meta-analysis of the osteoporosis acid-ash diet hypothesis

Tanis R Fenton , Andrew W Lyon , Michael Eliasziw , Suzanne C Tough and David A Hanley


Background
The acid-ash hypothesis posits that increased excretion of "acidic" ions derived from the diet, such as phosphate, contributes to net acidic ion excretion, urine calcium excretion, demineralization of bone, and osteoporosis. The public is advised by various media to follow an alkaline diet to lower their acidic ion intakes. The objectives of this meta-analysis were to quantify the contribution of phosphate to bone loss in healthy adult subjects; specifically, a) to assess the effect of supplemental dietary phosphate on urine calcium, calcium balance, and markers of bone metabolism; and to assess whether these affects are altered by the b) level of calcium intake, c) the degree of protonation of the phosphate.

Methods
Literature was identified through computerized searches regarding phosphate with surrogate and/or direct markers of osteoporosis. Studies were assessed for methodological quality. Multiple linear regression analyses, weighted for sample size, were used to combine the study results. Tests of interaction included stratification by calcium intake and degree of protonation of the phosphate supplement.

Results
Twelve studies including 30 intervention arms manipulated 269 subjects' phosphate intakes. Three studies reported net acid excretion. All of the meta-analyses demonstrated significant decreases in urine calcium excretion in response to phosphate supplements whether the calcium intake was high or low, regardless of the degree of protonation of the phosphate supplement. None of the meta-analyses revealed lower calcium balance in response to increased phosphate intakes, whether the calcium intake was high or low, or the composition of the phosphate supplement.

Conclusions
All of the findings from this meta-analysis were contrary to the acid ash hypothesis. Higher phosphate intakes were associated with decreased urine calcium and increased calcium retention. This meta-analysis did not find evidence that phosphate intake contributes to demineralization of bone or to bone calcium excretion in the urine. Dietary advice that dairy products, meats, and grains are detrimental to bone health due to "acidic" phosphate content needs reassessment. There is no evidence that higher phosphate intakes are detrimental to bone health.

Effects of a Diet Higher in Carbohydrate/Lower in Fat Versus Lower in Carbohydrate/Higher in Monounsaturated Fat on Postmeal Triglyceride Concentrations and Other Cardiovascular Risk Factors in Type 1 Diabetes

Effects of a Diet Higher in Carbohydrate/Lower in Fat Versus Lower in Carbohydrate/Higher in Monounsaturated Fat on Postmeal Triglyceride Concentrations and Other Cardiovascular Risk Factors in Type 1 Diabetes

from Diabetes Care Journal current issue by Strychar, I., Cohn, J. S., Renier, G., Rivard, M., Aris-Jilwan, N., Beauregard, H., Meltzer, S., Belanger, A., Dumas, R., Ishac, A., Radwan, F., Yale, J.-F.
OBJECTIVE

To compare the effects of a eucaloric diet higher in carbohydrate/lower in fat versus lower in carbohydrate/higher in monounsaturated fat on postmeal triglyceride (TG) concentrations and other cardiovascular disease risk factors in nonobese subjects with type 1 diabetes and in good glycemic control.
RESEARCH DESIGN AND METHODS

In a parallel group design study, 30 subjects were randomly assigned and completed one of the two eucaloric diets. Assessments included: BMI, blood pressure, A1C, plasma lipids, and markers of oxidation, thrombosis, and inflammation. At 6 months, subjects were hospitalized for 24 h to measure plasma TG excursions.
RESULTS

There were no significant differences between groups other than decreased plasminogen activator inhibitor 1 (PAI-1) levels and weight gain in the lower-carbohydrate/higher–monounsaturated fat group. During the 24-h testing, the lower-carbohydrate/higher–monounsaturated fat group had a lower plasma TG profile.
CONCLUSIONS

A diet lower in carbohydrate/higher in monounsaturated fat could offer an appropriate choice for nonobese type 1 diabetic individuals with good metabolic and weight control.

n-3 PUFA: bioavailability and modulation of adipose tissue function.

n-3 PUFA: bioavailability and modulation of adipose tissue function.

Kopecky J, Rossmeisl M, Flachs P, Kuda O, Brauner P, Jilkova Z, Stankova B, Tvrzicka E, Bryhn M.

Department of Adipose Tissue Biology, Institute of Physiology of the Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague, Czech Republic.

Adipose tissue has a key role in the development of metabolic syndrome (MS), which includes obesity, type 2 diabetes, dyslipidaemia, hypertension and other disorders. Systemic insulin resistance represents a major factor contributing to the development of MS in obesity. The resistance is precipitated by impaired adipose tissue glucose and lipid metabolism, linked to a low-grade inflammation of adipose tissue and secretion of pro-inflammatory adipokines. Development of MS could be delayed by lifestyle modifications, while both dietary and pharmacological interventions are required for the successful therapy of MS. The n-3 long-chain (LC) PUFA, EPA and DHA, which are abundant in marine fish, act as hypolipidaemic factors, reduce cardiac events and decrease the progression of atherosclerosis. Thus, n-3 LC PUFA represent healthy constituents of diets for patients with MS. In rodents n-3 LC PUFA prevent the development of obesity and impaired glucose tolerance. The effects of n-3 LC PUFA are mediated transcriptionally by AMP-activated protein kinase and by other mechanisms. n-3 LC PUFA activate a metabolic switch toward lipid catabolism and suppression of lipogenesis, i.e. in the liver, adipose tissue and small intestine. This metabolic switch improves dyslipidaemia and reduces ectopic deposition of lipids, resulting in improved insulin signalling. Despite a relatively low accumulation of n-3 LC PUFA in adipose tissue lipids, adipose tissue is specifically linked to the beneficial effects of n-3 LC PUFA, as indicated by (1) the prevention of adipose tissue hyperplasia and hypertrophy, (2) the induction of mitochondrial biogenesis in adipocytes, (3) the induction of adiponectin and (4) the amelioration of adipose tissue inflammation by n-3 LC PUFA.

Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men

Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men

from Journal of Applied Physiology recent issues by Tang, J. E., Moore, D. R., Kujbida, G. W., Tarnopolsky, M. A., Phillips, S. M.

This study was designed to compare the acute response of mixed muscle protein synthesis (MPS) to rapidly (i.e., whey hydrolysate and soy) and slowly (i.e., micellar casein) digested proteins both at rest and after resistance exercise. Three groups of healthy young men (n = 6 per group) performed a bout of unilateral leg resistance exercise followed by the consumption of a drink containing an equivalent content of essential amino acids (10 g) as either whey hydrolysate, micellar casein, or soy protein isolate. Mixed MPS was determined by a primed constant infusion of l-[ring-13C6]phenylalanine. Ingestion of whey protein resulted in a larger increase in blood essential amino acid, branched-chain amino acid, and leucine concentrations than either casein or soy (P < 0.05). Mixed MPS at rest (determined in the nonexercised leg) was higher with ingestion of faster proteins (whey = 0.091 ± 0.015, soy = 0.078 ± 0.014, casein = 0.047 ± 0.008%/h); MPS after consumption of whey was ~93% greater than casein (P < 0.01) and ~18% greater than soy (P = 0.067). A similar result was observed after exercise (whey > soy > casein); MPS following whey consumption was ~122% greater than casein (P < 0.01) and 31% greater than soy (P < 0.05). MPS was also greater with soy consumption at rest (64%) and following resistance exercise (69%) compared with casein (both P < 0.01). We conclude that the feeding-induced simulation of MPS in young men is greater after whey hydrolysate or soy protein consumption than casein both at rest and after resistance exercise; moreover, despite both being fast proteins, whey hydrolysate stimulated MPS to a greater degree than soy after resistance exercise. These differences may be related to how quickly the proteins are digested (i.e., fast vs. slow) or possibly to small differences in leucine content of each protein.

Green tea and death from pneumonia in Japan: the Ohsaki cohort study

Green tea and death from pneumonia in Japan: the Ohsaki cohort study

[Nutritional epidemiology and public health]

from American Journal of Clinical Nutrition current issue by Watanabe, I., Kuriyama, S., Kakizaki, M., Sone, T., Ohmori-Matsuda, K., Nakaya, N., Hozawa, A., Tsuji, I.

Background: Experimental and animal studies have shown the activities of catechins, the main constituents of green tea, against infectious agents. No data are available on the association between green tea consumption and the risk of pneumonia in humans.

Objective: We examined the association between green tea consumption and death from pneumonia in humans.

Design: We conducted a population-based cohort study, with follow-up from 1995 to 2006. The participants were National Health Insurance beneficiaries in Japan (19,079 men and 21,493 women aged 40–79 y). We excluded participants for whom data on green tea consumption frequency were missing or who had reported a history of cancer, myocardial infarction, stroke, and extreme daily energy intake at baseline. We used Cox proportional hazards regression analysis to calculate hazard ratios (HRs) and their 95% CIs for death from pneumonia according to green tea consumption.

Results: Over 12 y of follow-up, we documented 406 deaths from pneumonia. In women, the multivariate HRs of death from pneumonia that were associated with different frequencies of green tea consumption were 1.00 (reference) for <1 cup/d, 0.59 (95% CI: 0.36, 0.98) for 1–2 cups/d, 0.55 (95% CI: 0.33, 0.91) for 3–4 cups/d, and 0.53 (95% CI: 0.33, 0.83) for ≥5 cups/d, respectively (P for trend: 0.008). In men, no significant association was observed.

Conclusion: Green tea consumption was associated with a lower risk of death from pneumonia in Japanese women.

Dietary fiber intake and risk of breast cancer in postmenopausal women: the National Institutes of Health-AARP Diet and Health Study

Dietary fiber intake and risk of breast cancer in postmenopausal women: the National Institutes of Health-AARP Diet and Health Study

[Nutritional epidemiology and public health]

from American Journal of Clinical Nutrition current issue by Park, Y., Brinton, L. A, Subar, A. F, Hollenbeck, A., Schatzkin, A.

Background: Although dietary fiber has been hypothesized to lower risk of breast cancer by modulating estrogen metabolism, the association between dietary fiber intake and risk of breast cancer by hormone receptor status is unclear.

Objective: The objective was to examine the relation of dietary fiber intake to breast cancer by hormone receptor status and histologic type among postmenopausal women in the National Institutes of Health–AARP Diet and Health Study (n = 185,598; mean age: 62 y).

Design: Dietary intakes were assessed with a food-frequency questionnaire. Incident breast cancer cases were identified through linkage with state cancer registries. Cox proportional hazard models were used to estimate relative risks (RRs) and 2-sided 95% CIs.

Results: During an average of 7 y of follow-up, 5461 breast cancer cases were identified, of which 3341 cases had estrogen receptor (ER) and progesterone receptor (PR) status. Dietary fiber intake was inversely associated with breast cancer risk [RR for the highest quintile (Q5) compared with the lowest quintile (Q1): 0.87; 95% CI: 0.77, 0.98; P for trend: 0.02]. The inverse association appeared to be stronger for ER–/PR– tumors (RRQ5vsQ1: 0.56; 95% CI: 0.35, 0.90; P for trend: 0.008; 366 cases) than for ER+/PR+ tumors (RRQ5vsQ1: 0.95; 95% CI: 0.76, 1.20; P for trend: 0.47; 1641 cases). The RRQ5vsQ1 of lobular tumors was 0.66 (95% CI: 0.44, 0.97; P for trend: 0.04), and the RRQ5vsQ1 of ductal tumors was 0.90 (95% CI: 0.77, 1.04; P for trend: 0.10). Fiber from grains, fruit, vegetables, and beans was not related to breast cancer.

Conclusion: Our findings suggest that dietary fiber can play a role in preventing breast cancer through nonestrogen pathways among postmenopausal women.

Meat, eggs, dairy products, and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

Meat, eggs, dairy products, and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

[Nutritional epidemiology and public health]

from American Journal of Clinical Nutrition current issue by Pala, V., Krogh, V., Berrino, F., Sieri, S., Grioni, S., Tjonneland, A., Olsen, A., Jakobsen, M. U., Overvad, K., Clavel-Chapelon, F., Boutron-Ruault, M.-C., Romieu, I., Linseisen, J., Rohrmann, S., Boeing, H., Steffen, A., Trichopoulou, A., Benetou, V., Naska, A., Vineis, P., Tumino, R., Panico, S., Masala, G., Agnoli, C., Engeset, D., Skeie, G., Lund, E., Ardanaz, E., Navarro, C., Sanchez, M.-J., Amiano, P., Svatetz, C. A. G., Rodriguez, L., Wirfalt, E., Manjer, J., Lenner, P., Hallmans, G., Peeters, P. H., van Gils, C. H, Bueno-de-Mesquita, H B., van Duijnhoven, F. J., Key, T. J, Spencer, E., Bingham, S., Khaw, K.-T., Ferrari, P., Byrnes, G., Rinaldi, S., Norat, T., Michaud, D. S, Riboli, E.

Background: A Western diet is associated with breast cancer risk.

Objective: We investigated the relation of meat, egg, and dairy product consumption with breast cancer risk by using data from the European Prospective Investigation into Cancer and Nutrition (EPIC).

Design: Between 1992 and 2003, information on diet was collected from 319,826 women. Disease hazard ratios were estimated with multivariate Cox proportional hazard models.

Results: Breast cancer cases (n = 7119) were observed during 8.8 y (median) of follow-up. No consistent association was found between breast cancer risk and the consumption of any of the food groups under study, when analyzed by both categorical and continuous exposure variable models. High processed meat consumption was associated with a modest increase in breast cancer risk in the categorical model (hazard ratio: 1.10; 95% CI: 1.00, 1.20; highest compared with lowest quintile: P for trend = 0.07). Subgroup analyses suggested an association with butter consumption, limited to premenopausal women (hazard ratio: 1.28; 95% CI: 1.06, 1.53; highest compared with lowest quintile: P for trend = 0.21). Between-country heterogeneity was found for red meat (Q statistic = 18.03; P = 0.05) and was significantly explained (P = 0.023) by the proportion of meat cooked at high temperature.

Conclusions: We have not consistently identified intakes of meat, eggs, or dairy products as risk factors for breast cancer. Future studies should investigate the possible role of high-temperature cooking in the relation of red meat intake with breast cancer risk.

One-carbon metabolism-related nutrients and prostate cancer survival

One-carbon metabolism-related nutrients and prostate cancer survival 

[Cancer]

from American Journal of Clinical Nutrition current issue by Kasperzyk, J. L, Fall, K., Mucci, L. A, Hakansson, N., Wolk, A., Johansson, J.-E., Andersson, S.-O., Andren, O.

Background: Folate and other one-carbon metabolism nutrients may influence prostate cancer pathogenesis. Prior studies of these nutrients in relation to prostate cancer incidence have been inconclusive, and none have explored prostate cancer survival.

Objective: The objective was to assess whether dietary intakes of folate, riboflavin, vitamin B-6, vitamin B-12, and methionine measured around the time of prostate cancer diagnosis are associated with prostate cancer survival.

Design: This population-based prospective study comprised 525 men from Örebro, Sweden, who received a diagnosis of incident prostate cancer between 1989 and 1994 and completed a self-administered food-frequency questionnaire. Record linkages to the Swedish Death Registry enabled all cases to be followed for up to 20 y after diagnosis, and the cause of death was assigned via medical record review. Cox proportional hazards regression was used to calculate multivariable hazard ratios (HRs) and 95% CIs. During a median of 6.4 y of follow-up, 218 men (42%) died of prostate cancer and 257 (49%) of other causes.

Results: A comparison of the highest with the lowest quartile showed that vitamin B-6 intake was inversely associated with prostate cancer–specific death (HR: 0.71; 95% CI: 0.46, 1.10; P for trend = 0.08), especially in men with a diagnosis of localized-stage disease (HR; 0.05; 95% CI: 0.01, 0.26; P for trend = 0.0003). However, vitamin B-6 intake was not associated with improved prostate cancer survival among advanced-stage cases (HR: 1.04; 95% CI: 0.64, 1.72; P for trend = 0.87). Folate, riboflavin, vitamin B-12, and methionine intakes were not associated with prostate cancer survival.

Conclusion: A high vitamin B-6 intake may improve prostate cancer survival among men with a diagnosis of localized-stage disease.

Comparison of dietary conjugated linoleic acid with safflower oil on body composition in obese postmenopausal women with type 2 diabetes mellitus

Comparison of dietary conjugated linoleic acid with safflower oil on body composition in obese postmenopausal women with type 2 diabetes mellitus

[Lipids]

from American Journal of Clinical Nutrition current issue by Norris, L. E, Collene, A. L, Asp, M. L, Hsu, J. C, Liu, L.-F., Richardson, J. R, Li, D., Bell, D., Osei, K., Jackson, R. D, Belury, M. A

Background: Weight loss may improve glucose control in persons with type 2 diabetes. The effects of fat quality, as opposed to quantity, on weight loss are not well understood.

Objective: We compared the effects of 2 dietary oils, conjugated linoleic acid (CLA) and safflower oil (SAF), on body weight and composition in obese postmenopausal women with type 2 diabetes.

Design: This was a 36-wk randomized, double-masked, crossover study. Fifty-five obese postmenopausal women with type 2 diabetes received SAF or CLA (8 g oil/d) during two 16-wk diet periods separated by a 4-wk washout period. Subjects met monthly with the study coordinator to receive new supplements and for assessment of energy balance, biochemical endpoints, or anthropometric variables.

Results: Thirty-five women completed the 36-wk intervention. Supplementation with CLA reduced body mass index (BMI) (P = 0.0022) and total adipose mass (P = 0.0187) without altering lean mass. The effect of CLA in lowering BMI was detected during the last 8 wk of each 16-wk diet period. In contrast, SAF had no effect on BMI or total adipose mass but reduced trunk adipose mass (P = 0.0422) and increased lean mass (P = 0.0432). SAF also significantly lowered fasting glucose (P = 0.0343) and increased adiponectin (P = 0.0051). No differences were observed in dietary energy intake, total fat intake, and fat quality in either diet period for either intervention.

Conclusions: Supplementation with CLA and SAF exerted different effects on BMI, total and trunk adipose mass, and lean tissue mass in obese postmenopausal women with type 2 diabetes. Supplementation with these dietary oils may be beneficial for weight loss, glycemic control, or both.

Anticancer and Cancer Chemopreventive Potential of Grape Seed Extract and Other Grape-Based Products

Anticancer and Cancer Chemopreventive Potential of Grape Seed Extract and Other Grape-Based Products

[Supplement: Grapes and Health]

from Journal of Nutrition current issue by Kaur, M., Agarwal, C., Agarwal, R.

With emerging trends in the incidence of cancer of various organ sites, additional approaches are needed to control human malignancies. Intervention or prevention of cancer by dietary constituents, a strategy defined as chemoprevention, holds great promise in our conquest to control cancer, because it can be implemented on a broader population base with less economic burden. Consistent with this, several epidemiological studies have shown that populations that consume diets rich in fruits and vegetables have an overall lower cancer incidence. Based on these encouraging observations, research efforts from across the globe have focused on identifying, characterizing, and providing scientific basis to the efficacy of various phytonutrients in an effort to develop effective strategy to control various human malignancies. Cancer induction, growth, and progression are multi-step events and numerous studies have demonstrated that various dietary agents interfere with these stages of cancer, thus blocking malignancy. Fruits and vegetables represent untapped reservoir of various nutritive and nonnutritive phytochemicals with potential cancer chemopreventive activity. Grapes and grape-based products are one such class of dietary products that have shown cancer chemopreventive potential and are also known to improve overall human health. This review focuses on recent advancements in cancer chemopreventive and anticancer efficacy of grape seed extract and other grape-based products. Overall, completed studies from various scientific groups conclude that both grapes and grape-based products are excellent sources of various anticancer agents and their regular consumption should thus be beneficial to the general population.