Modified alternate-day fasting and cardioprotection: relation to adipose tissue dynamics and dietary fat intake.

Modified alternate-day fasting and cardioprotection: relation to adipose tissue dynamics and dietary fat intake.

Varady KA, Hudak CS, Hellerstein MK.

Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60612, USA. kvarady@gmail.com

The relation between alternate-day fasting (ADF) and cardioprotection remains uncertain. In the present study, we examined the ability of modified ADF, with a low-fat (LF) vs high-fat (HF) background diet, to modulate adipose tissue physiology in a way that may protect against coronary heart disease. In a 4-week study, male C57BL/6 mice were randomized to 1 of 3 groups: (1) ADF-85%-LF (85% energy restriction on fast day, ad libitum fed on feed day, on an LF diet), (2) ADF-85%-HF (same protocol but HF diet), and (3) control (ad libitum fed). Throughout the study, body weight did not differ between ADF and control animals. Proportion of subcutaneous fat increased (P < .01), whereas the proportion of visceral fat decreased (P < .01), in both ADF groups. Triglyceride (TG) synthesis was augmented (P < .05) in subcutaneous fat, but remained unchanged in visceral fat. Adiponectin concentrations were elevated (P < .05), whereas leptin and resistin levels decreased (P < .05). Aortic vascular smooth muscle cell proliferation was reduced (P < .05) by 60% and 76% on the LF and HF diets, respectively. Plasma total cholesterol, TG, and free fatty acid concentrations also decreased (P < .05). In summary, modified ADF regimens alter adipose tissue physiology (ie, body fat distribution, TG metabolism, and adipokines) in a way that may protect against coronary heart disease. These beneficial effects were noted over a wide range of fat intake, suggesting that ADF may be protective even in the presence of HF diets.

Skeletal muscle fat and carbohydrate metabolism during recovery from glycogen-depleting exercise in humans.

Skeletal muscle fat and carbohydrate metabolism during recovery from glycogen-depleting exercise in humans.

Kimber NE, Heigenhauser GJ, Spriet LL, Dyck DJ.
Department of Human Biology and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
The primary aim of the present study was to determine whether intramuscular triacylglycerol (IMTG) utilization contributed significantly to the increase in lipid oxidation during recovery from exercise, as determined from the muscle biopsy technique. In addition, we also examined the regulation of pyruvate dehydrogenase (PDHa) and changes in muscle acetyl units during an 18 h recovery period after glycogen-depleting exercise. Eight endurance-trained males completed an exhaustive bout of exercise (approximately 90 min) on a cycle ergometer followed by ingestion of carbohydrate (CHO)-rich meals (64-70 % of energy from carbohydrate) at 1, 4 and 7 h of recovery. Duplicate muscle biopsies were obtained at exhaustion, and 3, 6 and 18 h of recovery. Despite the large intake of CHO during recovery (491 +/- 28 g or 6.8 +/- 0.3 g kg-1), respiratory exchange ratio values of 0.77 to 0.84 indicated a greater reliance on lipid as an oxidative fuel. However, there was no net IMTG utilization during recovery. IMTG content at exhaustion was 23.5 +/- 3.5 mmol (kg dry wt)-1, and remained constant at 24.6 +/- 2.6, 25.7 +/- 2.8 and 28.4 +/- 3.0 mmol (kg dry wt)-1 after 3, 6 and 18 h of recovery. Muscle glycogen increased significantly from 37 +/- 11 mmol (kg dry wt)-1 at exhaustion, to 165 +/- 13, 250 +/- 18, and 424 +/- 22 mmol (kg dry wt)-1 at 3, 6 and 18 h of recovery, respectively. PDHa was reduced at 6 and 18 h when compared to exhaustion, but did not change during the recovery period. Acetyl-CoA, acetylcarnitine and pyruvate contents declined significantly after 3 h of recovery compared to exhaustion, and thereafter remained unchanged. We conclude that IMTG has a negligible role in contributing to the enhanced fat oxidation during recovery from exhaustive exercise. Despite the elevation of glucose and insulin following high-CHO meals during recovery, CHO oxidation and PDH activation were decreased, supporting the hypothesis that glycogen resynthesis is of high metabolic priority. Plasma fatty acids, very low density lipoprotein triacylglycerols, as well as intramuscular acetylcarnitine stores are likely to be important fuel sources for aerobic energy, particularly during the first few hours of recovery.

Protein and amino acids for athletes.

Title: Protein and amino acids for athletes.

Personal Authors: Tipton, K. D., Wolfe, R. R.

Author Affiliation: Department of Surgery, University of Texas Medical Branch, Shriner's Hospital for Children, 815 Market Street, Galveston, TX 77550, USA.

Editors: Maughan, R. J., Burke, L. M., Coyle, E. F.

Document Title: Food, nutrition and sports performance II. The International Olympic Committee Consensus Conference on sports nutrition

Abstract:

The main determinants of an athlete's protein needs are their training regime and habitual nutrient intake. Most athletes ingest sufficient protein in their habitual diet. Additional protein will confer only a minimal, albeit arguably important, additional advantage. Given sufficient energy intake, lean body mass can be maintained within a wide range of protein intakes. Since there is limited evidence for harmful effects of a high protein intake and there is a metabolic rationale for the efficacy of an increase in protein, if muscle hypertrophy is the goal, a higher protein intake within the context of an athlete's overall dietary requirements may be beneficial. However, there are few convincing outcome data to indicate that the ingestion of a high amount of protein (2-3 g . kg-1 BW . day-1, where BW=body weight) is necessary. Current literature suggests that it may be too simplistic to rely on recommendations of a particular amount of protein per day. Acute studies suggest that for any given amount of protein, the metabolic response is dependent on other factors, including the timing of ingestion in relation to exercise and/or other nutrients, the composition of ingested amino acids and the type of protein.

Tea Polyphenols Decrease Serum Levels of Prostate-Specific Antigen, Hepatocyte Growth Factor, and Vascular Endothelial Growth Factor in Prostate Cancer Patients and Inhibit Production of Hepatocyte Growth Factor and Vascular Endothelial Growth Factor

Tea Polyphenols Decrease Serum Levels of Prostate-Specific Antigen, Hepatocyte Growth Factor, and Vascular Endothelial Growth Factor in Prostate Cancer Patients and Inhibit Production of Hepatocyte Growth Factor and Vascular Endothelial Growth Factor In vitro
Jerry McLarty2,4, Rebecca L.H. Bigelow1,2, Mylinh Smith2, Don Elmajian2,3, Murali Ankem5 and James A. Cardelli1,2

Authors' Affiliations: 1 Department of Microbiology and Immunology, 2 Feist-Weiller Cancer Center, 3 Department of Urology, and 4 Department of Medicine, Louisiana State University Health Sciences Center; and 5 Overton Brooks VA Medical Center, Shreveport, Louisiana

Requests for reprints: James A. Cardelli, Department of Microbiology/Immunology, Louisiana State University Health Sciences Center at Shreveport, 1501 Kings Highway, Shreveport, LA 71130. Phone: 318-675-5756; Fax: 318-675-5764; E-mail: jcarde@lsuhsc.edu.


The purpose of this study was to determine the effects of short-term supplementation with the active compounds in green tea on serum biomarkers in patients with prostate cancer.

Twenty-six men with positive prostate biopsies and scheduled for radical prostatectomy were given daily doses of Polyphenon E, which contained 800 mg of (–)-epigallocatechin-3-gallate (EGCG) and lesser amounts of (–)-epicatechin, (–)-epigallocatechin, and (–)-epicatechin-3-gallate (a total of 1.3 g of tea polyphenols), until time of radical prostatectomy. Serum was collected before initiation of the drug study and on the day of prostatectomy. Serum biomarkers hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF)-I, IGF binding protein-3 (IGFBP-3), and prostate-specific antigen (PSA) were analyzed by ELISA. Toxicity was monitored primarily through liver function enzymes. Changes in serum components were analyzed statistically using the Wilcoxon signed rank test. Cancer-associated fibroblasts were treated with EGCG, and HGF and VEGF protein and mRNA levels were measured.

HGF, VEGF, PSA, IGF-I, IGFBP-3, and the IGF-I/IGFBP-3 ratio decreased significantly during the study. All of the liver function tests also decreased, five of them significantly: total protein, albumin, aspartate aminotransferase, alkaline phosphatase, and amylase. The decrease in HGF and VEGF was confirmed in prostate cancer–associated fibroblasts in vitro.

Our results show a significant reduction in serum levels of PSA, HGF, and VEGF in men with prostate cancer after brief treatment with EGCG (Polyphenon E), with no elevation of liver enzymes. These findings support a potential role for Polyphenon E in the treatment or prevention of prostate cancer.

Fruit and vegetable intakes and subsequent changes in body weight in European populations: results from the project on Diet, Obesity, and Genes (DiOGenes)

Fruit and vegetable intakes and subsequent changes in body weight in European populations: results from the project on Diet, Obesity, and Genes (DiOGenes)

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

Background: High fruit and vegetable intakes may limit weight gain, particularly in susceptible persons, such as those who stop smoking.

Objective: The objective was to assess the association of fruit and vegetable intake with subsequent weight change in a large-scale prospective study.

Design: The data used were from 89,432 men and women from 5 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). The association between fruit and vegetable intake and weight change after a mean follow-up of 6.5 y was assessed by linear regression. Polytomous logistic regression was used to evaluate whether fruit and vegetable intake relates to weight gain, weight loss, or both.

Results: Per 100-g intake of fruit and vegetables, weight change was –14 g/y (95% CI: –19, –9 g/y). In those who stopped smoking during follow-up, this value was –37 g/y (95% CI: –58, –15 g/y; P for interaction < 0.0001). When weight gain and loss were analyzed separately per 100-g intake of fruit and vegetables in a combined model, the odds ratios (95% CIs) were 0.97 (0.95, 0.98) for weight gain ≥0.5 and <1 kg/y, 0.94 (0.92, 0.96) for weight gain ≥1 kg/y, and 0.97 (0.95, 0.99) for weight loss ≥0.5 kg/y. In those who stopped smoking during follow-up, the odds ratios (95% CIs) were 0.93 (0.88, 0.99), 0.87 (0.81, 0.92), and 0.97 (0.88, 1.07), respectively (P for interaction < 0.0001).

Conclusions: Fruit and vegetable intake relates significantly, albeit weakly inversely, to weight change. For persons who stop smoking, high fruit and vegetable intakes may be recommended to reduce the risk of weight gain.

Longitudinal study of serum carotenoid, retinol, and tocopherol concentrations in relation to breast cancer risk among postmenopausal women

Longitudinal study of serum carotenoid, retinol, and tocopherol concentrations in relation to breast cancer risk among postmenopausal women

from American Journal of Clinical Nutrition current issue by Kabat, G. C, Kim, M., Adams-Campbell, L. L, Caan, B. J, Chlebowski, R. T, Neuhouser, M. L, Shikany, J. M, Rohan, T. E

Background: Prospective studies have examined the association of serum and plasma carotenoids and micronutrients and breast cancer; however, to date, studies have only assessed exposure at one point in time.

Objective: This study analyzed baseline and repeated serum measurements of carotenoids, retinol, and tocopherols to assess their associations with postmenopausal breast cancer risk.

Design: Serum concentrations of -carotene, β-carotene, β-cryptoxanthin, lycopene, lutein + zeaxanthin, retinol, -tocopherol, and -tocopherol were measured in a 6% sample of women in the Women's Health Initiative clinical trials at baseline and at years 1, 3, and 6 and in a 1% sample of women in the observational study at baseline and at year 3. The association of baseline compounds and breast cancer risk was estimated by Cox proportional hazards models. In addition, repeated measurements were analyzed as time-dependent covariates. Of 5450 women with baseline measurements, 190 incident cases of breast cancer were ascertained over a median of 8.0 y of follow-up.

Results: After multivariable adjustment, risk of invasive breast cancer was inversely associated with baseline serum -carotene concentrations (hazard ratio for highest compared with the lowest tertile: 0.55; 95% CI: 0.34, 0.90; P = 0.02) and positively associated with baseline lycopene (hazard ratio: 1.47; 95% CI: 0.98, 2.22; P = 0.06). Analysis of repeated measurements indicated that -carotene and β-carotene were inversely associated with breast cancer and that -tocopherol was associated with increased risk.

Conclusions: The present study, which was the first to assess repeated measurements of serum carotenoids and micronutrients in relation to breast cancer, adds to the evidence of an inverse association of specific carotenoids with breast cancer. The positive associations observed for lycopene and -tocopherol require confirmation.

Skim milk compared with a fruit drink acutely reduces appetite and energy intake in overweight men and women

Skim milk compared with a fruit drink acutely reduces appetite and energy intake in overweight men and women

from American Journal of Clinical Nutrition current issue by Dove, E. R, Hodgson, J. M, Puddey, I. B, Beilin, L. J, Lee, Y. P, Mori, T. A

Background: Several studies show that proteins, including whey and casein, are more satiating than carbohydrates. It follows that skim milk would be more satiating than sugar-rich beverages. However, this has yet to be shown.

Objective: The objective was to investigate the effects of drinking skim milk in comparison with a fruit drink at breakfast on self-reported postmeal satiety and energy intake at lunch.

Design: In a randomized crossover trial, 34 overweight women (n = 21) and men (n = 13) attended 2 sessions 1 wk apart. At each session, participants consumed a fixed-energy breakfast together with either 600 mL skim milk (25 g protein, 36 g lactose, <1 g fat; 1062 kJ) or 600 mL fruit drink (<1 g protein, 63 g sugar, <1 g fat; 1062 kJ). Participants provided satiety ratings throughout the morning. Four hours after breakfast they consumed an ad libitum lunch, and energy intake was assessed.

Results: Participants consumed significantly less energy at lunch after consuming skim milk (mean: 2432 kJ; 95% CI: 2160, 2704 kJ) than after consuming the fruit drink (mean: 2658 kJ; 95% CI: 2386, 2930 kJ), with a mean difference of 8.5% (P < 0.05). In addition, self-reports of satiety were higher throughout the morning after consumption of skim milk than after consumption of the fruit drink (P < 0.05) with the differences becoming larger over the 4 h (P < 0.05).

Conclusion: Consumption of skim milk, in comparison with a fruit drink, leads to increased perceptions of satiety and to decreased energy intake at a subsequent meal.

Effects of walnut consumption on blood lipids and other cardiovascular risk factors: a meta-analysis and systematic review

Effects of walnut consumption on blood lipids and other cardiovascular risk factors: a meta-analysis and systematic review

from American Journal of Clinical Nutrition current issue by Banel, D. K, Hu, F. B

Background: Consumption of nuts has been associated with a decreased risk of cardiovascular disease events and death. Walnuts in particular have a unique profile: they are rich in polyunsaturated fatty acids, which may improve blood lipids and other cardiovascular disease risk factors.

Objectives: We aimed to conduct a literature review and a meta-analysis to combine the results from several trials and to estimate the effect of walnuts on blood lipids.

Design: Literature databases were searched for published trials that compared a specifically walnut-enhanced diet with a control diet. We conducted a random-effects meta-analysis of weighted mean differences (WMDs) of lipid outcomes.

Results: Thirteen studies representing 365 participants were included in the analysis. Diets lasted 4–24 wk with walnuts providing 10–24% of total calories. When compared with control diets, diets supplemented with walnuts resulted in a significantly greater decrease in total cholesterol and in LDL-cholesterol concentrations (total cholesterol: WMD = –10.3 mg/dL, P < 0.001; LDL cholesterol: WMD = –9.2 mg/dL, P < 0.001). HDL cholesterol and triglycerides were not significantly affected by walnut diets more than with control diets (HDL cholesterol: WMD = –0.2, P = 0.8; triglycerides: WMD = –3.9, P = 0.3). Other results reported in the trials indicated that walnuts provided significant benefits for certain antioxidant capacity and inflammatory markers and had no adverse effects on body weight [body mass index (kg/m2): WMD = –0.4, P = 0.5; weight (kg): WMD = –0.05, P = 0.97].

Conclusions: Overall, high-walnut-enriched diets significantly decreased total and LDL cholesterol for the duration of the short-term trials. Larger and longer-term trials are needed to address the effects of walnut consumption on cardiovascular risk and body weight.

Long-term effects of a very-low-carbohydrate weight loss diet compared with an isocaloric low-fat diet after 12 mo

Long-term effects of a very-low-carbohydrate weight loss diet compared with an isocaloric low-fat diet after 12 mo
from American Journal of Clinical Nutrition current issue by Brinkworth, G. D, Noakes, M., Buckley, J. D, Keogh, J. B, Clifton, P. M

Background: Long-term weight loss and cardiometabolic effects of a very-low-carbohydrate, high-saturated-fat diet (LC) and a high-carbohydrate, low-fat diet (LF) have not been evaluated under isocaloric conditions.

Objective: The objective was to compare an energy-controlled LC diet with an LF diet at 1 y.

Design: Men and women (n = 118) with abdominal obesity and at least one additional metabolic syndrome risk factor were randomly assigned to either an energy-restricted (6–7 MJ) LC diet (4%, 35%, and 61% of energy as carbohydrate, protein, and fat, respectively) or an isocaloric LF diet (46%, 24%, and 30% of energy as carbohydrate, protein, and fat, respectively) for 1 y. Weight, body composition, and cardiometabolic risk markers were assessed.

Results: Sixty-nine participants (59%) completed the trial: 33 in the LC group and 36 in the LF group. Both groups lost similar amounts of weight (LC: –14.5 ± 1.7 kg; LF: –11.5 ± 1.2 kg; P = 0.14, time x diet) and body fat (LC: –11.3 ± 1.5 kg; LF: –9.4 ± 1.2 kg; P = 0.30). Blood pressure, fasting glucose, insulin, insulin resistance, and C-reactive protein decreased independently of diet composition. Compared with the LF group, the LC group had greater decreases in triglycerides (–0.36 ± 0.15 mmol/L; 95% CI: –0.67, –0.05 mmol/L; P = 0.011), increases in HDL cholesterol (0.23 ± 0.09 mmol/L; 95% CI: 0.06, 0.40 mmol/L; P = 0.018) and LDL cholesterol (0.6 ± 0.2 mmol/L; 95% CI: 0.2, 1.0 mmol/L; P = 0.001), and a greater but nonsignificant increase in apolipoprotein B (0.08 ± 0.04 g/L; 95% CI: –0.004, 0.171 g/L; P = 0.17).

Conclusions: Under planned isoenergetic conditions, as expected, both dietary patterns resulted in similar weight loss and changes in body composition. The LC diet may offer clinical benefits to obese persons with insulin resistance. However, the increase in LDL cholesterol with the LC diet suggests that this measure should be monitored.

Conjugated Linoleic Acids Reduce Body Fat in Healthy Postmenopausal Women

Conjugated Linoleic Acids Reduce Body Fat in Healthy Postmenopausal Women

from Journal of Nutrition current issue by Raff, M., Tholstrup, T., Toubro, S., Bruun, J. M., Lund, P., Straarup, E. M., Christensen, R., Sandberg, M. B., Mandrup, S.

Isomers of conjugated linoleic acids (CLA) reduce fat mass (FM) and increase insulin sensitivity in some, but not all, murine studies. In humans, this effect is still debatable. In this study, we compared the effect of 2 CLA supplements on total and regional FM assessed by dual energy X-ray absorptiometry, changes in serum insulin and glucose concentrations, and adipose tissue (AT) gene expression in humans. In a double-blind, parallel, 16-wk intervention, we randomized 81 healthy postmenopausal women to 1) 5.5 g/d of 40/40% of cis9,trans11-CLA (c9,t11-CLA) and trans10,cis12-CLA (t10,c12-CLA) (CLA-mix); 2) cis9, trans11-CLA (c9,t11-CLA); or 3) control (olive oil). We assessed all variables before and after the intervention. The CLA-mix group had less total FM (4%) and lower-body FM (7%) than the control (P = 0.02 and < 0.001, respectively). Post hoc analyses showed that serum insulin concentrations were greater in the CLA-mix group (34%) than the control group (P = 0.02) in the highest waist circumference tertile only. AT mRNA expression of glucose transporter 4, leptin, and lipoprotein lipase was lower, whereas expression of tumor necrosis factor- was higher in the CLA-mix group than in the control group (P < 0.04). In conclusion, a 50:50 mixture of c9,t11- and t10,c12-CLA isomers resulted in less total and lower-body FM in postmenopausal women and greater serum insulin concentrations in the highest waist circumference tertile. Future research is needed to confirm the insulin desensitizing effect of the CLA mixture and the effect on the mRNA expression of adipocyte-specific genes in humans.

Regular Consumption of Nuts Is Associated with a Lower Risk of Cardiovascular Disease in Women with Type 2 Diabetes

Regular Consumption of Nuts Is Associated with a Lower Risk of Cardiovascular Disease in Women with Type 2 Diabetes

from Journal of Nutrition current issue by Li, T. Y., Brennan, A. M., Wedick, N. M., Mantzoros, C., Rifai, N., Hu, F. B.

Higher nut consumption has been associated with lower risk of coronary heart disease (CHD) events in several epidemiologic studies. The study examined the association between intake of nuts and incident cardiovascular disease (CVD) in a cohort of women with type 2 diabetes. For the primary analysis, there were 6309 women with type 2 diabetes who completed a validated FFQ every 2–4 y between 1980 and 2002 and were without CVD or cancer at study entry. Major CVD events included incident myocardial infarction (MI), revascularization, and stroke. During 54,656 person-years of follow-up, there were 452 CHD events (including MI and revascularization) and 182 incident stroke cases. Frequent nut and peanut butter consumption was inversely associated with total CVD risk in age-adjusted analyses. After adjustment for conventional CVD risk factors, consumption of at least 5 servings/wk of nuts or peanut butter [serving size, 28 g (1 ounce) for nuts and 16 g (1 tablespoon) for peanut butter] was significantly associated with a lower risk of CVD (relative risk = 0.56; 95% CI: 0.36–0.89). Furthermore, when we evaluated plasma lipid and inflammatory biomarkers, we observed that increasing nut consumption was significantly associated with a more favorable plasma lipid profile, including lower LDL cholesterol, non-HDL cholesterol, total cholesterol, and apolipoprotein-B-100 concentrations. However, we did not observe significant associations for HDL cholesterol or inflammatory markers. These data suggest that frequent nut and peanut butter consumption is associated with a significantly lower CVD risk in women with type 2 diabetes.

Nonlinear Periodization Maximizes Strength Gains in Split Resistance Training Routines.

Nonlinear Periodization Maximizes Strength Gains in Split Resistance Training Routines.

Monteiro AG, Aoki MS, Evangelista AL, Alveno DA, Monteiro GA, Piçarro ID, Ugrinowitsch C.

Department of Rehabilitation, Federal University of Sao Paulo-UNIFESP, Sao Paulo, Brazil; 2School of Arts, Sciences and Humanities, University of São Paulo, Sao Paulo, SP, Brazil; 3University City of Sao Paulo-UNICID, Sao Paulo, Brazil; and 4Department of Sport, School of Physical Education and Sport, University of São Paulo, Sao Paulo, SP, Brazil.

Monteiro, AG, Aoki, MS, Evangelista, AL, Alveno, DA, Monteiro, GA, Piçarro, IDC, and Ugrinowitsch, C. Nonlinear periodization maximizes strength gains in split resistance training routines. J Strength Cond Res 00(0): 1-6, 2009-The purpose of our study was to compare strength gains after 12 weeks of nonperiodized (NP), linear periodized (LP), and nonlinear periodized (NLP) resistance training models using split training routines. Twenty-seven strength-trained men were recruited and randomly assigned to one of 3 balanced groups: NP, LP, and NLP. Strength gains in the leg press and in the bench press exercises were assessed. There were no differences between the training groups in the exercise pre-tests (p > 0.05) (i.e., bench press and leg press). The NLP group was the only group to significantly increase maximum strength in the bench press throughout the 12-week training period. In this group, upper-body strength increased significantly from pre-training to 4 weeks (p < 0.0001), from 4 to 8 weeks (p = 0.004), and from 8 weeks to the post-training (p < 0.02). The NLP group also exhibited an increase in leg press 1 repetition maximum at each time point (pre-training to 4 weeks, 4-8 week, and 8 weeks to post-training, p < 0.0001). The LP group demonstrated strength increases only after the eight training week (p = 0.02). There were no further strength increases from the 8-week to the post-training test. The NP group showed no strength increments after the 12-week training period. No differences were observed in the anthropometric profiles among the training models. In summary, our data suggest that NLP was more effective in increasing both upper- and lower-body strength for trained subjects using split routines.

Obesity and Migraine: The Effect of Age, Gender and Adipose Tissue Distribution.

Obesity and Migraine: The Effect of Age, Gender and Adipose Tissue Distribution.

Peterlin BL, Rosso AL, Rapoport AM, Scher AI.

From the Drexel University College of Medicine - Neurology, Philadelphia, PA, USA (B.L. Peterlin and A.L. Rosso); UCLA - Neurology, Los Angeles, CA, USA (A.M. Rapoport); Uniformed Services University - Preventive Medicine Biometrics, Bethesda, MD, USA (A.I. Scher).

(Headache 2009;**:**-**) Objective.- To evaluate the prevalence of migraine/severe headaches in those with and without general obesity and abdominal obesity (Abd-O) and the effect of gender and age on this relationship. Background.- General, or total body obesity (TBO), as estimated by body mass index, is a risk factor for migraine chronification. However, there are conflicting data as to whether TBO is associated with migraine prevalence. Abd-O has been shown to be a better predictor of various disease states than TBO, but has not been evaluated in general population studies in association with migraine. Methods.- Data from a general population survey, the National Health and Nutrition Examination Survey, were used to obtain demographics, self-report of migraine/severe headaches and measured body mass indices, including height, weight, and waist circumference. All analyses were stratified by age and gender and multivariate analyses were determined through use of logistic regression models. Results.- A total of 21,783 participants were included in the analysis. Between 20-55 years of age, the prevalence of migraine was increased in both men and women with TBO as compared with those without, (P </= .001). Migraine was also more prevalent in those with Abd-O as compared with those without (men: 20.1% vs 15.9%, P < .001; women: 36.9% vs 28.8.2%, P < .001). After 55 years of age, the prevalence of migraine in men was no longer associated with either TBO or Abd-O. Similarly, after 55 years of age, the prevalence of migraine in women was no longer associated with TBO. However, in women older than 55 years, the prevalence of migraine was decreased in those with Abd-O as compared with those without Abd-O (14.4% vs 17.4%, P < .05). After adjusting for demographics, cardiovascular risk factors and Abd-O, results were similar for the association between migraine prevalence and TBO in both younger and older men and women. After adjusting for demographics, cardiovascular risk factors and TBO, migraine prevalence was no longer associated with Abd-O in younger men, but remained associated with an increased odds ratio of having migraine in younger women, as well as a decreased odds ratio in older women. Conclusion.- The relationship between migraine and obesity varies by age, gender, and adipose tissue distribution (eg, TBO vs Abd-O). In men and women </=55 years old, migraine prevalence is increased in those with TBO, independent of Abd-O. In addition, in men and women </=55 years old, migraine prevalence is increased in those with Abd-O; and in women this association is independent of TBO. In men older than 55 years, migraine is not associated with either TBO or Abd-O. However, in women older than 55 years, migraine prevalence is decreased in those with Abd-O and is independent of TBO.

Antidepressant activity of zinc and magnesium in view of the current hypotheses of antidepressant action.

Antidepressant activity of zinc and magnesium in view of the current hypotheses of antidepressant action.

Szewczyk B, Poleszak E, Sowa-Kućma M, Siwek M, Dudek D, Ryszewska-Pokraśniewicz B, Radziwoń-Zaleska M, Opoka W, Czekaj J, Pilc A, Nowak G.

Department of Neurobiology, Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, PL 31-343 Kraków, Poland. szewczyk@if-pan.krakow.pl

The clinical efficacy of current antidepressant therapies is unsatisfactory; antidepressants induce a variety of unwanted effects, and, moreover, their therapeutic mechanism is not clearly understood. Thus, a search for better and safer agents is continuously in progress. Recently, studies have demonstrated that zinc and magnesium possess antidepressant properties. Zinc and magnesium exhibit antidepressant-like activity in a variety of tests and models in laboratory animals. They are active in forced swim and tail suspension tests in mice and rats, and, furthermore, they enhance the activity of conventional antidepressants (e.g., imipramine and citalopram). Zinc demonstrates activity in the olfactory bulbectomy, chronic mild and chronic unpredictable stress models in rats, while magnesium is active in stress-induced depression-like behavior in mice. Clinical studies demonstrate that the efficacy of pharmacotherapy is enhanced by supplementation with zinc and magnesium. The antidepressant mechanisms of zinc and magnesium are discussed in the context of glutamate, brain-derived neurotrophic factor (BDNF) and glycogen synthase kinase-3 (GSK-3) hypotheses. All the available data indicate the importance of zinc and magnesium homeostasis in the psychopathology and therapy of affective disorders.

Effect of calcium from dairy and dietary supplements on faecal fat excretion: a meta-analysis of randomized controlled trials.

Obes Rev. 2009 Jun 1. [Epub ahead of print]

Effect of calcium from dairy and dietary supplements on faecal fat excretion: a meta-analysis of randomized controlled trials.

Christensen R, Lorenzen JK, Svith CR, Bartels EM, Melanson EL, Saris WH, Tremblay A, Astrup A.

The Parker Institute, Musculoskeletal Statistics Unit, Frederiksberg Hospital, Frederiksberg, Denmark.

Summary Observational studies have found that dietary calcium intake is inversely related to body weight and body fat mass. One explanatory mechanism is that dietary calcium increases faecal fat excretion. To examine the effect of calcium from dietary supplements or dairy products on quantitative faecal fat excretion, we performed a systematic review with meta-analysis. We included randomized, controlled trials of calcium (supplements or dairy) in healthy subjects, where faecal fat excretion was measured. Meta-analyses used random-effects models with changes in faecal fat excreted expressed as standardized mean differences, as the studies assessed the same outcome but measured in different ways. An increased calcium intake resulted in increased excretion of faecal fat by a standardized mean difference of 0.99 (95% confidence intervals: 0.63-1.34; P < 0.0001; expected to correspond to approximately 2g day(-1)) with moderate heterogeneity (I(2) = 49.5%) indicating some inconsistency in trial outcomes. However, the dairy trials showed homogeneous outcomes (I(2)=0%) indicating consistency among these trials. We estimated that increasing the dairy calcium intake by 1241 mg day(-1) resulted in an increase in faecal fat of 5.2 (1.6-8.8) g day(-1). In conclusion, dietary calcium has the potential to increase faecal fat excretion to an extent that could be relevant for prevention of weight (re-)gain. Long-term studies are required to establish its potential contribution.

Excretion of endogenous boldione in human urine: influence of phytosterol consumption.

    Excretion of endogenous boldione in human urine: influence of phytosterol consumption.

    Verheyden K, Noppe H, Vanhaecke L, Wille K, Bussche JV, Bekaert K, Thas O, Janssen CR, De Brabander HF.
    Ghent University, Faculty of Veterinary Medicine, Research Group of Veterinary Public Health and Zoonoses, Laboratory of Chemical Analysis, Salisburylaan 133, B-9820 Merelbeke, Belgium.
    Boldenone (17-hydroxy-androsta-1,4-diene-3-one, Bol) and boldione (androst-1,4-diene-3,17-dione, ADD), are currently listed as exogenous anabolic steroids by the World Anti-Doping Agency. However, it has been reported that these analytes can be produced endogenously. Interestingly, only for Bol a comment is included in the list on its potential endogenous origin. In this study, the endogenous origin of ADD in human urine was investigated, and the potential influence of phytosterol consumption was evaluated.We carried out a 5-week in vivo trial with both men (n=6) and women (n=6) and measured alpha-boldenone, ss-boldenone, boldione, androstenedione, ss-testosterone and alpha-testosterone in their urine using gas chromatography coupled to multiple mass spectrometry (GC-MS-MS). The results demonstrate that endogenous ADD is sporadically produced at concentrations ranging from 0.751ngmL(-1) to 1.73ngmL(-1), whereas endogenous Bol could not be proven. We also tested the effect of the daily consumption of a commercially available phytosterol-enriched yogurt drink on the presence of these analytes in human urine. Results from this study could not indicate a relation of ADD-excretion with the consumption of phytosterols at the recommended dose. The correlations between ADD and other steroids were consistently stronger for volunteers consuming phytosterols (test) than for those refraining from phytosterol consumption (control). Excretion of AED, bT and aT did not appear to be dependent on the consumption of phytosterols.This preliminary in vivo trial indicates the endogenous origin of boldione or ADD in human urine, independent on the presence of any structural related analytes such as phytosterols.

Influence of sex on total and regional fat loss in overweight and obese men and women

Influence of sex on total and regional fat loss in overweight and obese men and women
J L Kuk1 and R Ross2
   1. 1School of Kinesiology and Health Science, Faculty of Health Science, York University, Toronto, Ontario, Canada
   2. 2School of Kinesiology and Health Studies, Department of Medicine, Division of Endocrinology and Metabolism, Queen's University, Kingston, Ontario, Canada
Received 26 November 2008; Revised 4 February 2009; Accepted 8 February 2009; Published online 10 March 2009.
Abstract
Objective:
To determine the influence of sex on the association between reductions in body weight (BW) and waist circumference (WC) with reductions in total (TAT), subcutaneous (SAT) and visceral adipose tissue (VAT) in response to lifestyle-based interventions.
Design:
Changes in TAT, SAT and VAT were assessed using magnetic resonance imaging in 81 men and 72 women who had participated in various diet and/or exercise interventions at Queen's University, Ontario, Canada.
Results:
Reductions in BW and WC were significantly (P<0.001) correlated with TAT, SAT and VAT loss in men and women. For a given weight loss, men had a significantly greater decrease in WC than women, and the sex difference in WC reduction increased with increasing weight loss (P<0.05). Similarly, for a given reduction in BW or WC, men have significantly greater reductions in VAT, but smaller reductions in total and lower body SAT than women, differences that progressively increased in magnitude with the increasing BW or WC loss (P<0.05). Accordingly, there were no sex differences in the TAT reduction for a given BW or WC reduction (P>0.05). Reductions in BW and WC were both independent predictors of VAT loss.
Conclusions:
These observations suggest that for a given reduction in BW or WC, men lose more VAT and less SAT than women; however, the TAT loss observed for a given reduction in BW or WC in men and women is not different.

Prospective study of nut consumption, long-term weight change, and obesity risk in women

Prospective study of nut consumption, long-term weight change, and obesity risk in women

from American Journal of Clinical Nutrition current issue by Bes-Rastrollo, M., Wedick, N. M, Martinez-Gonzalez, M. A., Li, T. Y, Sampson, L., Hu, F. B

Background: Data concerning the long-term association between nut consumption and weight change in a free-living population are sparse.

Objective: The objective was to determine the relation between nut consumption and long-term weight change.

Design: The participants were 51,188 women in the Nurses' Health Study II aged 20–45 y, who had no cardiovascular disease, diabetes, or cancer. We prospectively evaluated the dietary intake of nuts and subsequent weight changes from 1991 to 1999.

Results: Women who reported eating nuts ?2 times/wk had slightly less mean (± SE) weight gain (5.04 ± 0.12 kg) than did women who rarely ate nuts (5.55 ± 0.04 kg) (P for trend < 0.001). For the same comparison, when total nut consumption was subdivided into peanuts and tree nuts, the results were similar (ie, less weight gain in women eating either peanuts or tree nuts ?2 times/wk). The results were similar in normal-weight, overweight, and obese participants. In multivariate analyses in which lifestyle and other dietary factors were controlled for, we found that greater nut consumption (?2 times/wk compared with never/almost never) was associated with a slightly lower risk of obesity (hazard ratio: 0.77; 95% CI: 0.57, 1.02; P for trend = 0.003).

Conclusions: Higher nut consumption was not associated with greater body weight gain during 8 y of follow-up in healthy middle-aged women. Instead, it was associated with a slightly lower risk of weight gain and obesity. The results of this study suggest that incorporating nuts into diets does not lead to greater weight gain and may help weight control.

Appl Physiol Nutr Metab. 2009 Jun;34(3):403-10.Related Articles, Links Physiologic and molecular bases of muscle hypertrophy and atrophy: impact of resistance exercise on human skeletal muscle (protein and exercise dose effects). Phillips SM. Exercis

Physiologic and molecular bases of muscle hypertrophy and atrophy: impact of resistance exercise on human skeletal muscle (protein and exercise dose effects).

Phillips SM.

Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, 1280 Main St. West, Hamilton, ON L8S 4K1, Canada (e-mail: phillis@mcmaster.ca).

Normally, skeletal muscle mass is unchanged, beyond periods of growth, but it begins to decline in the fourth or fifth decade of life. The mass of skeletal muscle is maintained by ingestion of protein-containing meals. With feeding, muscle protein synthesis (MPS) is stimulated and a small suppression of muscle protein breakdown (MPB) occurs, such that protein balance becomes positive (MPS > MPB). As the postprandial period subsides and a transition toward fasting occurs, the balance of muscle protein turnover becomes negative again (MPB > MPS). Thus, during maintenance of skeletal muscle mass, the long-term net result is that MPS is balanced by MPB. Acutely, however, it is of interest to determine what regulates feeding-induced increases in MPS, since it appears that, in a number of scenarios (for example aging, disuse, and wasting diseases), a suppression of MPS in response to feeding is a common finding. In fact, recent findings point to the fact that loss of skeletal muscle mass with disuse and aging is due not chronic changes in MPS or MPB, but to a blunted feeding-induced rise in MPS. Resistance exercise is a potent stimulator of MPS and appears to synergistically enhance the gains stimulated by feeding. As such, resistance exercise is an important countermeasure to disuse atrophy and to age-related declines in skeletal muscle mass. What is less well understood is how the intensity and volume of the resistance exercise stimulus is sufficient to result in rises in MPS. Recent advances in this area are discussed here, with a focus on human in vivo data.

Almonds have a neutral effect on serum lipid profiles: a meta-analysis of randomized trials.

Almonds have a neutral effect on serum lipid profiles: a meta-analysis of randomized trials.

Phung OJ, Makanji SS, White CM, Coleman CI.

University of Connecticut, Hartford Hospital Evidence-Based Practice Center, Hartford, CT 06102-5037, USA.

Almond consumption may be associated with improvements in serum lipid profiles. The aim was to evaluate the influence of almonds on lipid parameters to help define the role of almonds as a lipid modulator. MEDLINE, EMBASE, Cochrane CENTRAL, and the Natural Medicines Comprehensive Database were searched through July 2008, with no language restrictions, for randomized controlled trials of almonds in human patients that reported efficacy data on at least one of the following endpoints: total, low-density lipoprotein (LDL), or high-density lipoprotein (HDL) cholesterol, triglycerides, or the LDL:HDL ratio. A manual search of references from primary or review articles was performed to identify additional relevant trials. Five randomized, controlled trials (totaling 142 participants) met all inclusion criteria. Upon meta-analysis, almond consumption ranging from 25 to 168 g/day significantly lowered total cholesterol [weighted mean difference -6.95 mg/dL (95% confidence interval [CI] -13.12 to -0.772) (-0.18 mmol/L [95% CI -0.34 to -0.02])] and showed a strong trend toward reducing LDL cholesterol [weighted mean difference -5.79 mg/dL (95% CI -11.2 to 0.00) (-0.15 mmol/L [95% CI -0.29 to 0.00])]. No significant effect on HDL cholesterol, triglycerides, or LDL:HDL ratio was found. No statistical heterogeneity was observed for any analysis (I2=0% for all). Review of funnel plots and the Egger's weighted regression statistic P values suggested a low likelihood of publication bias in all analyses (P>0.25 for all). Almond consumption may decrease total cholesterol and does not significantly affect LDL or HDL cholesterol, triglycerides, or the LDL:HDL ratio. The current body of randomized trials does not support the ingestion of almonds solely for their lipid modifying effects. Both the lipid modulating effects and the safety/tolerability of almonds should be further investigated through the conduction of larger randomized, double-blinded trials of longer duration. Such studies might focus specifically on whether the efficacy of almonds as a lipid modulator varies by dose or comorbidity.

Calcium absorption from fortified ice cream formulations compared with calcium absorption from milk.

Calcium absorption from fortified ice cream formulations compared with calcium absorption from milk.

van der Hee RM, Miret S, Slettenaar M, Duchateau GS, Rietveld AG, Wilkinson JE, Quail PJ, Berry MJ, Dainty JR, Teucher B, Fairweather-Tait SJ.

Unilever Food and Health Research Institute, PO Box 114, 3130 AC Vlaardingen, The Netherlands. Regine-van-der.Hee@unilever.com

OBJECTIVE: Optimal bone mass in early adulthood is achieved through appropriate diet and lifestyle, thereby protecting against osteoporosis and risk of bone fracture in later life. Calcium and vitamin D are essential to build adequate bones, but calcium intakes of many population groups do not meet dietary reference values. In addition, changes in dietary patterns are exacerbating the problem, thereby emphasizing the important role of calcium-rich food products. We have designed a calcium-fortified ice cream formulation that is lower in fat than regular ice cream and could provide a useful source of additional dietary calcium. Calcium absorption from two different ice cream formulations was determined in young adults and compared with milk. SUBJECTS/SETTING: Sixteen healthy volunteers (25 to 45 years of age), recruited from the general public of The Netherlands, participated in a randomized, reference-controlled, double-blind cross-over study in which two test products and milk were consumed with a light standard breakfast on three separate occasions: a standard portion of ice cream (60 g) fortified with milk minerals and containing a low level (3%) of butter fat, ice cream (60 g) fortified with milk minerals and containing a typical level (9%) of coconut oil, and reduced-fat milk (1.7% milk fat) (200 mL). Calcium absorption was measured by the dual-label stable isotope technique. STATISTICAL ANALYSIS: Effects on calcium absorption were evaluated by analysis of variance. RESULTS: Fractional absorption of calcium from the 3% butterfat ice cream, 9% coconut oil ice cream, and milk was 26%+/-8%, 28%+/-5%, and 31%+/-9%, respectively, and did not differ significantly (P=0.159). CONCLUSIONS: Results indicate that calcium bioavailability in the two calcium-fortified ice cream formulations used in this study is as high as milk, indicating that ice cream may be a good vehicle for delivery of calcium.

Effects of a popular exercise and weight loss program on weight loss, body composition, energy expenditure and health in obese women

Effects of a popular exercise and weight loss program on weight loss, body composition, energy expenditure and health in obese women

from Nutrition & Metabolism - Latest articles 

by Chad Kerksick, Ashli Thomas, Bill Campbell, Lem Taylor, Colin Wilborn, Brandon Marcello, Mike Roberts, Emily Pfau, Megan Grimstvedt, Jasmine Opusunju, Teresa Magrans-Courtney, Chris Rasmussen, Ron Wilson and Richard Kreider

Objective

To determine the safety and efficacy of altering the ratio of carbohydrate and protein in low-energy diets in conjunction with a popular exercise program in obese women. Design: 

Matched, prospective clinical intervention study to assess efficacy of varying ratios of carbohydrate and protein intake in conjunction with a regular exercise program. Participants: 

One-hundred sixty one sedentary, obese, pre-menopausal women (38.5+/-8.5 yrs, 164.2+/-6.7 cm, 94.2+/-18.8 kg, 34.9+/-6.4 kg * m-2, 43.8+/-4.2 %) participated in this study. Participants were weight stable and not participating in additional weight loss programs. All participants were medically cleared for disease and were excluded if they were taking any form of dietary supplementation to facilitate weight loss and/or any were currently being treated with other prescription medications. Methods: 

Participants were assigned to either a no exercise + no diet control (CON), a no diet + exercise group (ND), or one of four diet + exercise groups (presented as kcals; % carbohydrate: protein: fat): 1) a high energy, high carbohydrate (CHO), low protein diet (HED) [2,600; 55:15:30 %], 2) a very low carbohydrate, high protein diet (VLCHP) [1,200 kcals; 63:7:30 %], 3) a low carbohydrate, moderate protein diet (LCMP) [1,200 kcals; 50:20:30 %] and 4) a high carbohydrate, low protein diet (HCLP) [1,200 kcals; 55:15:30 %]. Participants in exercise groups (all but CON) performed a pneumatic resistance, circuit training program under supervision three times per week. 

Measurements: 

At 0, 2, 10 and 14 weeks, anthropometric, body composition, resting energy expenditure (REE), fasting blood samples, and muscular fitness assessments were completed. 

Results: 

All groups except CON experienced significant reductions (P<0.05 - 0.001) in waist circumference over 14 weeks. VLCHP, LCHP and LPHC participants experienced similar but significant (P<0.05 - 0.001) reductions in body mass when compared to other groups. Delta responses indicated that fat loss after 14 weeks was significantly greatest in VLCHP (95% CI: -5.2, -3.2 kg), LCMP (-4.0, -1.9 kg) and HCLP (-3.8, -2.1 kg) when compared to other groups. Subsequent reductions in % body fat were significantly greater in VLCHP, LCMP and HCLP participants. Initial dieting decreased (P<0.05) relative REE similarly in all groups. All exercise groups significantly (P<0.05) improved in muscular fitness, but these improvements were not different among groups. Favorable but non-significant mean changes occurred in lipid panels, glucose and HOMA-IR. Leptin levels decreased (P<0.05) in all groups, except for CON, after two weeks of dieting and remained lower throughout the 14 week program. Exercise participation resulted in significant improvements in quality of life and body image. 

Conclusions: 

Exercise alone (ND) appears to have minimal impact on measured outcomes with positive outcomes apparent when exercise is combined with a hypoenergetic diet. Greater improvements in waist circumference and body composition occurred when carbohydrate is replaced in the diet with protein. Weight loss in all diet groups (VLCHP, LCMP and HCLP) was primarily fat and stimulated improvements in markers of cardiovascular disease risk, body composition, energy expenditure and psychosocial parameters.

Minimal Resistance Training Improves Daily Energy Expenditure and Fat Oxidation.

Minimal Resistance Training Improves Daily Energy Expenditure and Fat Oxidation.

Kirk EP, Donnelly JE, Smith BK, Honas J, Lecheminant JD, Bailey BW, Jacobsen DJ, Washburn RA.


Long-term resistance training (RT) may result in a chronic increase in 24-h energy expenditure (EE) and fat oxidation to a level sufficient to assist in maintaining energy balance and preventing weight gain. However, the impact of a minimal RT program on these parameters in an overweight college-aged population, a group at high risk for developing obesity, is unknown. PURPOSE:: We aimed to evaluate the effect of 6 months of supervised minimal RT in previously sedentary, overweight (mean +/- SEM, BMI = 27.7 +/- 0.5 kg.m) young adults (21.0 +/- 0.5 yr) on 24-h EE, resting metabolic rate (RMR), sleep metabolic rate (SMR), and substrate oxidation using whole-room indirect calorimetry 72 h after the last RT session. METHODS:: Participants were randomized to RT (one set, 3 d.wk, three to six repetition maximums, nine exercises; N = 22) or control (C, N = 17) groups and completed all assessments at baseline and at 6 months. RESULTS:: There was a significant (P < 0.05) increase in 24-h EE in the RT (527 +/- 220 kJ.d) and C (270 +/- 168 kJ.d) groups; however, the difference between groups was not significant (P = 0.30). Twenty-four hours of fat oxidation (g.d) was not altered after RT; however, reductions in RT assessed during both rest (P < 0.05) and sleep (P < 0.05) suggested increased fat oxidation in RT compared with C during these periods. SMR (8.4 +/- 8.6%) and RMR (7.4 +/- 8.7%) increased significantly in RT (P < 0.001) but not in C, resulting in significant (P < 0.001) between-group differences for SMR with a trend for significant (P = 0.07) between-group differences for RMR. CONCLUSION:: A minimal RT program that required little time to complete (11min per session) resulted in a chronic increase in energy expenditure. This adaptation in energy expenditure may have a favorable impact on energy balance and fat oxidation sufficient to assist with the prevention of obesity in sedentary, overweight young adults, a group at high risk for developing obesity.

Preliminary data about the influence of vitamin D status on the loss of body fat in young overweight/obese women following two types of hypocaloric diet.

Preliminary data about the influence of vitamin D status on the loss of body fat in young overweight/obese women following two types of hypocaloric diet.

Ortega RM, Aparicio A, Rodríguez-Rodríguez E, Bermejo LM, Perea JM, López-Sobaler AM, Ruiz-Roso B, Andrés P.

Departamento de Nutrición, Facultad de Farmacia, Universidad Complutense, Madrid 28040, Spain. rortega@farm.ucm.es

The loss of weight was analysed in a group of sixty overweight/obese women of childbearing age (20-35 years) according to their initial vitamin D status. Subjects were randomly assigned to one of two slightly hypocaloric diets: Diet V, in which the consumption of vegetables was increased, or Diet C, in which the relative consumption of cereals (especially breakfast cereals) was increased. Dietetic, anthropometric and biochemical data were collected at the start of the study and again at 2 weeks after dividing the women into groups depending on their having an initial serum 25-hydroxyvitamin D (25(OH)D) concentration of < 50 nmol/l (LD) or>or=50 nmol/l (HD). Dietary intervention led to a reduction in energy intake, body weight and BMI in all groups. The HD women showed greater body fat losses during the study than the LD women (1.7 (SD 1.8) kg compared to 0.5 (SD 0.8) kg). A better vitamin D status therefore aided the loss of body fat over the experimental period (OR 0.462; CI 0.271, 0.785; P < 0.001). However, when the dietary groups were analysed separately, this effect was only seen in the C subjects (OR 0.300; CI 0.121, 0.748; P < 0.001). The present results suggest that women with a better vitamin D status respond more positively to hypocaloric diets and lose more body fat; this was especially clear among the C subjects who had a greater vitamin D supply during the experimental period.

Vitamin D3 enhances mood in healthy subjects during winter.

Vitamin D3 enhances mood in healthy subjects during winter.

Lansdowne AT, Provost SC.

Department of Psychology, The University of Newcastle, Callaghan NSW, Australia.

Mood changes synchronised to the seasons exist on a continuum between individuals, with anxiety and depression increasing during the winter months. An extreme form of seasonality is manifested as the clinical syndrome of seasonal affective disorder (SAD) with carbohydrate craving, hypersomnia, lethargy, and changes in circadian rhythms also evident. It has been suggested that seasonality and the symptoms of SAD may be due to changing levels of vitamin D3, the hormone of sunlight, leading to changes in brain serotonin. Forty-four healthy subjects were given 400 IU, 800 IU, or no vitamin D3 for 5 days during late winter in a random double-blind study. Results on a self-report measure showed that vitamin D3 significantly enhanced positive affect and there was some evidence of a reduction in negative affect. Results are discussed in terms of their implications for seasonality, SAD, serotonin, food preference, sleep, and circadian rhythms.

Green tea: potential health benefits.

Green tea: potential health benefits.

Schneider C, Segre T.

Department of Family Medicine, Maine Medical Center, Portland, Maine 04102, USA.

Green tea has been used widely and in high doses for centuries as a health tonic in many societies. Evidence suggests that green tea is effective for treating genital warts. There is some supportive evidence for the use of green tea in cancer prevention. Drinking green tea is associated with a decrease in all-cause mortality, but not in cancer-related mortality. Small clinical studies have found that green tea may also be helpful in losing and managing weight, and lowering cholesterol. Epidemiologic evidence suggests that green tea may prevent stroke and cardiovascular disease. Green tea appears to be safe, although there have been case reports of hepatotoxicity possibly related to a specific extract in pill or beverage form. Green tea seems to be a low-risk complementary therapy for a number of conditions, but more studies are needed.

Effects of selenite and genistein on G2/M cell cycle arrest and apoptosis in human prostate cancer cells.

Effects of selenite and genistein on G2/M cell cycle arrest and apoptosis in human prostate cancer cells.

Zhao R, Xiang N, Domann FE, Zhong W.

Department of Pathology and Laboratory Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792, USA.

Combination of chemopreventive agents with distinct molecular mechanisms is considered to offer a potential for enhancing cancer prevention efficacy while minimizing toxicity. Here we report two chemopreventive agents, selenite and genistein, that have synergistic effects on apoptosis, cell cycle arrest, and associated signaling pathways in p53-expressing LNCaP and p53-null PC3 prostate cancer cells. We show that selenite induced apoptosis only, whereas genistein induced both apoptosis and G2/M cell cycle arrest. Combination of these two agents exhibited enhanced effects, which were slightly greater in LNCaP than PC3 cells. Selenite or genistein alone upregulated protein levels of p53 in LNCaP cells only and p21(waf1) and Bax in both cell lines. Additionally, genistein inhibited AKT phosphorylation. Downregulation of AKT by siRNA caused apoptosis and G2/M cell cycle arrest and masked the effects of genistein. Treatment with insulin-like growth factor I (IGF-I) elevated levels of total and phosphorylated AKT and suppressed the effects of genistein. Neither downregulation of AKT nor IGF-I treatment altered the cellular effects of selenite. Our study demonstrates that selenium and genistein act via different molecular mechanisms and exhibit enhanced anticancer effects, suggesting that a combination of selenium and genistein may offer better efficacy and reduction of toxicity in prostate cancer prevention.

Fatty Fish Intake Decreases Lipids Related to Inflammation and Insulin Signaling—A Lipidomics Approach

Fatty Fish Intake Decreases Lipids Related to Inflammation and Insulin Signaling—A Lipidomics Approach

by Maria Lankinen et al.

Background

The evidence of the multiple beneficial health effects of fish consumption is strong, but physiological mechanisms behind these effects are not completely known. Little information is available on the effects of consumption of different type of fish. The aim of this study was to investigate how fatty fish or lean fish in a diet affect serum lipidomic profiles in subjects with coronary heart disease.

Methodology and Principal Findings

A pilot study was designed which included altogether 33 subjects with myocardial infarction or unstable ischemic attack in an 8-week parallel controlled intervention. The subjects were randomized to either fatty fish (n = 11), lean fish (n = 12) or control (n = 10) groups. Subjects in the fish groups had 4 fish meals per week and subjects in the control group consumed lean beef, pork and chicken. A fish meal was allowed once a week maximum. Lipidomics analyses were performed using ultra performance liquid chromatography coupled to electrospray ionization mass spectrometry and gas chromatography. Multiple bioactive lipid species, including ceramides, lysophosphatidylcholines and diacylglycerols, decreased significantly in the fatty fish group, whereas in the lean fish group cholesterol esters and specific long-chain triacylglycerols increased significantly (False Discovery Rate q-value <0.05).

Conclusions/Significance

The 8-week consumption of fatty fish decreased lipids which are potential mediators of lipid-induced insulin resistance and inflammation, and may be related to the protective effects of fatty fish on the progression of atherosclerotic vascular diseases or insulin resistance.

Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans

Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans

from Journal of Clinical Investigation

by Kimber L. Stanhope, Jean Marc Schwarz, Nancy L. Keim, Steven C. Griffen, Andrew A. Bremer, James L. Graham, Bonnie Hatcher, Chad L. Cox, Artem Dyachenko, Wei Zhang, John P. McGahan, Anthony Seibert, Ronald M. Krauss, Sally Chiu, Ernst J. Schaefer, Masumi Ai, Seiko Otokozawa, Katsuyuki Nakajima, Takamitsu Nakano, Carine Beysen, Marc K. Hellerstein, Lars Berglund, Peter J. Havel

Studies in animals have documented that, compared with glucose, dietary fructose induces dyslipidemia and insulin resistance. To assess the relative effects of these dietary sugars during sustained consumption in humans, overweight and obese subjects consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 weeks. Although both groups exhibited similar weight gain during the intervention, visceral adipose volume was significantly increased only in subjects consuming fructose. Fasting plasma triglyceride concentrations increased by approximately 10% during 10 weeks of glucose consumption but not after fructose consumption. In contrast, hepatic de novo lipogenesis (DNL) and the 23-hour postprandial triglyceride AUC were increased specifically during fructose consumption. Similarly, markers of altered lipid metabolism and lipoprotein remodeling, including fasting apoB, LDL, small dense LDL, oxidized LDL, and postprandial concentrations of remnant-like particle–triglyceride and –cholesterol significantly increased during fructose but not glucose consumption. In addition, fasting plasma glucose and insulin levels increased and insulin sensitivity decreased in subjects consuming fructose but not in those consuming glucose. These data suggest that dietary fructose specifically increases DNL, promotes dyslipidemia, decreases insulin sensitivity, and increases visceral adiposity in overweight/obese adults.

Dietary sugars: a fat difference

Dietary sugars: a fat difference

from Journal of Clinical Investigation

by Susanna M. Hofmann, Matthias H. 

Coronary heart disease is a major cause of morbidity and mortality in Western societies. The metabolic syndrome, characterized by obesity, insulin resistance, elevated blood pressure, elevated triglycerides, and low levels of high-density lipoprotein cholesterol, confers substantial risk of coronary heart disease. Current pathogenetic models suggest that postprandial hyperlipidemia is one specific metabolic abnormality that is typically associated with increased morbidity. In this issue of the JCI, Stanhope and colleagues demonstrate that consumption of fructose-sweetened but not glucose-sweetened beverages for 10 weeks increases de novo lipid synthesis, promotes dyslipidemia, impairs insulin sensitivity, and increases visceral adiposity in overweight or obese adults 

Walnuts and fatty fish influence different serum lipid fractions in normal to mildly hyperlipidemic individuals: a randomized controlled study

Walnuts and fatty fish influence different serum lipid fractions in normal to mildly hyperlipidemic individuals: a randomized controlled study

from American Journal of Clinical Nutrition current issue by Rajaram, S., Haddad, E. H., Mejia, A., Sabate, J.

Background: Increased consumption of n–3 (omega-3) fatty acids decreases the incidence of coronary heart disease (CHD).

Objective: The objective was to determine whether walnuts (plant n–3 fatty acid) and fatty fish (marine n–3 fatty acid) have similar effects on serum lipid markers at intakes recommended for primary prevention of CHD.

Design: In a randomized crossover feeding trial, 25 normal to mildly hyperlipidemic adults consumed 3 isoenergetic diets (30% total fat and <10% saturated fat) for 4 wk each: a control diet (no nuts or fish), a walnut diet (42.5 g walnuts/10.1 mJ), or a fish diet (113 g salmon, twice/wk). Fasting blood was drawn at baseline and at the end of each diet period and analyzed for serum lipids.

Results: Serum total cholesterol and LDL cholesterol concentrations in adults who followed the walnut diet (4.87 ± 0.18 and 2.77 ± 0.15 mmol/L, respectively) were lower than in those who followed the control diet (5.14 ± 0.18 and 3.06 ± 0.15 mmol/L, respectively) and those who followed the fish diet (5.33 ± 0.18 and 3.2 ± 0.15 mmol/L, respectively; P < 0.0001). The fish diet resulted in decreased serum triglyceride and increased HDL-cholesterol concentrations (1.0 ± 0.11 and 1.23 ± 0.05 mmol/L, respectively) compared with the control diet (1.12 ± 0.11 and 1.19 ± 0.05 mmol/L, respectively) and the walnut diet (1.11 ± 0.11 mmol/L, P < 0.05, and 1.18 ± 0.05 mmol/L, P < 0.001, respectively). The ratios of total cholesterol:HDL cholesterol, LDL cholesterol:HDL cholesterol, and apolipoprotein B:apolipoprotein A-I were lower (P < 0.05) in those who followed the walnut diet compared with those who followed the control and fish diets.

Conclusion: Including walnuts and fatty fish in a healthy diet lowered serum cholesterol and triglyceride concentrations, respectively, which affects CHD risk favorably.

Should dairy be recommended as part of a healthy vegetarian diet? Point

Should dairy be recommended as part of a healthy vegetarian diet? Point

from American Journal of Clinical Nutrition current issue by Weaver, C. M

A benefit-risk evaluation of the evidence for including dairy foods in the diet is presented. For many persons dairy products provide a substantial portion of essential nutrients, but especially calcium, potassium, and magnesium. Dietary supplements and fortified foods can be alternative sources of these nutrients, although other components of dairy foods such as amino acid composition and conjugated linoleic acid may be instrumental in the benefits associated with dairy product consumption for bone health and reduced risk of stroke, metabolic syndrome, and some cancers. Newer evidence shows that protein-induced calciuria does not have a detrimental effect on net calcium retention, and the concentrations of hormones in milk are not outside of the range of endogenous concentrations. Increased dietary protein, including from milk, can elevate serum concentrations of insulin-like growth factor I, which has an unknown relation to cancer. The concern over consumption of milk leading to increased risk of prostate cancer through reduction of serum 1,25-dihydroxyvitamin D, a potent anti-prostate cancer hormone, has been resolved with new evidence that local production of this hormone is independent of diet. Overall, evidence suggests that being a lactovegetarian has greater health benefits and reduced health risks than being a vegan.

Fruit, vegetables, and colorectal cancer risk: the European Prospective Investigation into Cancer and Nutrition

Fruit, vegetables, and colorectal cancer risk: the European Prospective Investigation into Cancer and Nutrition

from American Journal of Clinical Nutrition current issue by van Duijnhoven, F. J., Bueno-De-Mesquita, H B., Ferrari, P., Jenab, M., Boshuizen, H. C, Ros, M. M, Casagrande, C., Tjonneland, A., Olsen, A., Overvad, K., Thorlacius-Ussing, O., Clavel-Chapelon, F., Boutron-Ruault, M.-C., Morois, S., Kaaks, R., Linseisen, J., Boeing, H., Nothlings, U., Trichopoulou, A., Trichopoulos, D., Misirli, G., Palli, D., Sieri, S., Panico, S., Tumino, R., Vineis, P., Peeters, P. H., van Gils, C. H, Ocke, M. C, Lund, E., Engeset, D., Skeie, G., Suarez, L. R., Gonzalez, C. A, Sanchez, M.-J., Dorronsoro, M., Navarro, C., Barricarte, A., Berglund, G., Manjer, J., Hallmans, G., Palmqvist, R., Bingham, S. A, Khaw, K.-T., Key, T. J, Allen, N. E, Boffetta, P., Slimani, N., Rinaldi, S., Gallo, V., Norat, T., Riboli, E.

Background: A high consumption of fruit and vegetables is possibly associated with a decreased risk of colorectal cancer (CRC). However, the findings to date are inconsistent.

Objective: We examined the relation between self-reported usual consumption of fruit and vegetables and the incidence of CRC.

Design: In the European Prospective Investigation into Cancer and Nutrition (EPIC), 452,755 subjects (131,985 men and 320,770 women) completed a dietary questionnaire in 1992–2000 and were followed up for cancer incidence and mortality until 2006. A multivariate Cox proportional hazard model was used to estimate adjusted hazard ratios (HRs) and 95% CIs.

Results: After an average follow-up of 8.8 y, 2,819 incident CRC cases were reported. Consumption of fruit and vegetables was inversely associated with CRC in a comparison of the highest with the lowest EPIC-wide quintile of consumption (HR: 0.86; 95% CI: 0.75, 1.00; P for trend = 0.04), particularly with colon cancer risk (HR: 0.76; 95% CI: 0.63, 0.91; P for trend < 0.01). Only after exclusion of the first 2 y of follow-up were these findings corroborated by calibrated continuous analyses for a 100-g increase in consumption: HRs of 0.95 (95% CI: 0.91, 1.00; P = 0.04) and 0.94 (95% CI: 0.89, 0.99; P = 0.02), respectively. The association between fruit and vegetable consumption and CRC risk was inverse in never and former smokers, but positive in current smokers. This modifying effect was found for fruit and vegetables combined and for vegetables alone (P for interaction < 0.01 for both).

Conclusions: These findings suggest that a high consumption of fruit and vegetables is associated with a reduced risk of CRC, especially of colon cancer. This effect may depend on smoking status.

Effect of age and frailty on ghrelin and cholecystokinin responses to a meal test

Effect of age and frailty on ghrelin and cholecystokinin responses to a meal test

from American Journal of Clinical Nutrition current issue by Serra-Prat, M., Palomera, E., Clave, P., Puig-Domingo, M.

Background: Ghrelin and cholecystokinin (CCK) are among the peripheral signals that regulate hunger and satiety.

Objective: The objective was to assess whether ghrelin and CCK responses to a standard nutritional load are related to age and frailty.

Design: Ghrelin, CCK, insulin, glucose, and 4-h visual analog hunger scale curves after a standard nutritional load test (380 kcal) were described and compared between 3 groups: old (>75 y) and frail persons (group A), old (>75 y) but nonfrail persons (group B), and young (25–65 y) adults (group C).

Results: Frail persons showed no postprandial ghrelin suppression, and old subjects, frail and nonfrail, showed no significant postprandial ghrelin recovery compared with young adults. Frailty was also associated with lower fasting ghrelin concentrations. No differences in fasting CCK were observed between young and old persons; however, postprandial CCK concentrations were enhanced in young persons, whereas no frailty effect on the CCK curve was observed in the old subjects. No correlations between mean ghrelin and hunger values over time were found, but strong negative correlations were shown between CCK and hunger (group A: rs = –0.88, P = 0.009; group B: rs = –0.86, P = 0.014; group C: rs = –0.71, P = 0.071) and insulin and hunger (group A: rs = –0.901, P = 0.006; group B: rs = –0.964, P < 0.001; group C: rs = –0.929, P = 0.003).

Conclusions: Advanced age determines a poorer ghrelin postprandial recuperation phase, a reduced CCK postprandial response, and an exaggerated postprandial insulin release. A loss of ghrelin prandial rhythm is present in old frail persons. The impaired response of these hunger regulatory hormones with age might contribute to the mechanisms of anorexia associated with aging.

Meta-analysis of animal fat or animal protein intake and colorectal cancer

Meta-analysis of animal fat or animal protein intake and colorectal cancer

from American Journal of Clinical Nutrition current issue by Alexander, D. D, Cushing, C. A, Lowe, K. A, Sceurman, B., Roberts, M. A

Background: In the recent World Cancer Research Fund/American Institute for Cancer Research report of diet and cancer, it was concluded that there is limited but suggestive evidence that animal fat intake increases the risk of colorectal cancer.

Objective: To clarify this potential relation, we conducted meta-analyses across a variety of subgroups, incorporating data from additional studies.

Design: Analyses of high compared with low animal fat intakes and categorical dose-response evaluations were conducted. Subgroup analyses, consisting of evaluations by study design, sex, and tumor site were also performed.

Results: Six prospective cohort studies with comprehensive dietary assessments, contributing 1070 cases of colorectal cancer and 1.5 million person-years of follow-up, were identified. The summary relative risk estimate (SRRE) for these studies was 1.04 (95% CI: 0.83, 1.31; P for heterogeneity = 0.221) on the basis of high compared with low intakes. When data from case-control studies were combined with the cohort data, the resulting SRRE was 1.15 (95% CI: 0.93, 1.42) with increased variability (P for heterogeneity = 0.015). In our dose-response analysis of the cohort studies, no association between a 20-g/d increment in animal fat intake and colorectal cancer was observed (SRRE: 1.02; 95% CI: 0.95, 1.09). In a separate analysis of 3 prospective cohort studies that reported data for animal protein or meat protein, no significant association with colorectal cancer was observed (SRRE: 0.90; 95% CI: 0.70, 1.15).

Conclusion: On the basis of the results of this quantitative assessment, the available epidemiologic evidence does not appear to support an independent association between animal fat intake or animal protein intake and colorectal cancer.

Dietary protein and calcium interact to influence calcium retention: a controlled feeding study

Dietary protein and calcium interact to influence calcium retention: a controlled feeding study

from American Journal of Clinical Nutrition current issue by Hunt, J. R, Johnson, L. K, Fariba Roughead, Z.

Background: The effect of meat protein on calcium retention at different calcium intakes is unresolved.

Objective: The objective was to test the effect of dietary protein on calcium retention at low and high intakes of calcium.

Design: In a randomized controlled feeding study with a 2 x 2 factorial crossover design, healthy postmenopausal women (n = 27) consumed either 675 or 1510 mg Ca/d, with both low and high protein (providing 10% and 20% energy) for 7 wk each, separated by a 3-wk washout period. After 3 wk, the entire diet was extrinsically labeled with 47Ca, and isotope retention was monitored by whole-body scintillation counting. Clinical markers of calcium and bone metabolism were measured.

Results: High compared with low dietary protein significantly increased calcium retention from the low-calcium (29.5% compared with 26.0% absorbed) but not the high-calcium diet (18% absorbed). For the low-calcium diet, this effect nearly balanced a protein-related 0.5-mmol/d greater urinary calcium excretion. Protein-related calciuretic effects were independent of dietary calcium. Testing at 1, 2, 3, 5, and 7 wk showed no long-term adaptation in urinary acidity or urinary calcium excretion. High compared with low dietary protein decreased urinary deoxypyridinoline and increased serum insulin-like growth factor I without affecting parathyroid hormone, osteocalcin, bone-specific alkaline phosphatase, or tartrate-resistant acid phosphatase.

Conclusions: In healthy postmenopausal women, a moderate increase in dietary protein, from 10% to 20% of energy, slightly improved calcium absorption from a low-calcium diet, nearly compensating for a slight increase in urinary calcium excretion. Under practical dietary conditions, increased dietary protein from animal sources was not detrimental to calcium balance or short-term indicators of bone health.

Effects of dietary fatty acid composition on 24-h energy expenditure and chronic disease risk factors in men

Effects of dietary fatty acid composition on 24-h energy expenditure and chronic disease risk factors in men

from American Journal of Clinical Nutrition current issue by Cooper, J. A, Watras, A. C, Adams, A. K, Schoeller, D. A

Background: A high-fat (HF) diet and sedentary lifestyle are implicated in the development of obesity. Controlled feeding studies and measures of short-term resting energy expenditure (REE) have suggested that the type of dietary fat may alter energy expenditure (EE).

Objective: The objective was to examine the effects of an HF diet rich in either monounsaturated or saturated fatty acids (FAs) and of exercise on EE and chronic disease risk factors.

Design: Eight healthy men [age: 18–45 y; body mass index (in kg/m2): 22 ± 3] were randomly assigned in a 2 x 2 crossover design to 1 of 4 treatments: HF diet (50% of energy) with a high amount of saturated fat (22% of energy) plus exercise (SE) or a sedentary (SS) condition or a diet high in monounsaturated fat (30% of energy) plus exercise (UE) or a sedentary (US) condition. The subjects spent 5 d in a metabolic chamber and cycled at 45% of maximal oxygen uptake for 2 h each day during the exercise visits. Respiratory gases and urinary nitrogen were measured to determine 24-h EE. Resting metabolic rate was measured on days 2, 4, and 6.

Results: Average 24-h EE was not different with respect to dietary FA composition (3202 ± 146, 3208 ± 151, 2240 ± 82, and 2270 ± 104 for SE, UE, SS, and US, respectively). Total and LDL cholesterol and blood pressure were significantly greater after the SE and SS treatments than after the UE and US treatments.

Conclusion: Resting metabolic rate and 24-h EE were not significantly different after short-term exposure to an HF diet rich in monounsaturated FAs or after exposure to a diet rich in saturated FAs in healthy, nonobese men.

Vitamin D supplementation enhances the beneficial effects of weight loss on cardiovascular disease risk markers

Vitamin D supplementation enhances the beneficial effects of weight loss on cardiovascular disease risk markers

from American Journal of Clinical Nutrition current issue by Zittermann, A., Frisch, S., Berthold, H. K, Gotting, C., Kuhn, J., Kleesiek, K., Stehle, P., Koertke, H., Koerfer, R.

Background: High blood concentrations of parathyroid hormone and low concentrations of the vitamin D metabolites 25-hydroxyvitamin D [25(OH)D] and calcitriol are considered new cardiovascular disease risk markers. However, there is also evidence that calcitriol increases lipogenesis and decreases lipolysis.

Objective: We investigated the effect of vitamin D on weight loss and traditional and nontraditional cardiovascular disease risk markers in overweight subjects.

Design: Healthy overweight subjects (n = 200) with mean 25(OH)D concentrations of 30 nmol/L (12 ng/mL) received vitamin D (83 µg/d) or placebo in a double-blind manner for 12 mo while participating in a weight-reduction program.

Results: Weight loss was not affected significantly by vitamin D supplementation (–5.7 ± 5.8 kg) or placebo (–6.4 ± 5.6 kg). However, mean 25(OH)D and calcitriol concentrations increased by 55.5 nmol/L and 40.0 pmol/L, respectively, in the vitamin D group but by only 11.8 nmol/L and 9.3 pmol/L, respectively, in the placebo group (P < 0.001), whereas a more pronounced decrease occurred in the vitamin D group than in the placebo group in blood concentrations of parathyroid hormone (–26.5% compared with –18.7%; P = 0.014), triglycerides (–13.5% compared with +3.0%; P < 0.001), and the inflammation marker tumor necrosis factor- (–10.2% compared with –3.2%; P = 0.049). The beneficial biochemical effects were independent of the loss in body weight, fat mass, and sex. However, compared with placebo, vitamin D supplementation also increased LDL-cholesterol concentrations (+5.4% compared with –2.5%; P < 0.001).

Conclusions: The results indicate that a vitamin D supplement of 83 µg/d does not adversely affect weight loss and is able to significantly improve several cardiovascular disease risk markers in overweight subjects with inadequate vitamin D status participating in a weight-reduction program. This trial was registered at clinicaltrials.gov as NCT00493012.

Effect of a proprietary protein supplement on recovery indices following resistance exercise in strength/power athletes.

Amino Acids. 2009 Apr 4. [Epub ahead of print]Click here to read Links
Effect of a proprietary protein supplement on recovery indices following resistance exercise in strength/power athletes.
Hoffman JR, Ratamess NA, Tranchina CP, Rashti SL, Kang J, Faigenbaum AD.

Department of Health and Exercise Science, The College of New Jersey, PO Box 7718, Ewing, NJ, 08628-0718, USA, hoffmanj@tcnj.edu.

The effect of 42 g of protein ingested pre- and post-exercise on recovery from an acute resistance exercise session was examined in 15 male strength/power athletes who were randomly divided into a supplement (SUP) or placebo (PL) group. Subjects reported to the Human Performance Laboratory (HPL) on four separate occasions (T1-T4). Maximal strength [one repetition-maximum (1-RM)] testing was performed during T1. During T2 subjects performed four sets of ten repetitions at 80% of their 1-RM in the squat, dead lift and barbell lunge exercises with 90 s of rest between each set. Blood draws occurred at baseline (BL), immediate and 15 min post-exercise to determine testosterone, cortisol and creatine kinase (CK) concentrations. Subjects reported back to the HPL 24 (T3) and 48 h (T4) post-exercise for a BL blood draw and to perform four sets of ten repetitions with 80% of 1-RM for the squat exercise only. No differences in the number of repetitions performed in the squat exercise were seen between the groups at T2. Relative to T2, PL performed significantly (P < 0.05) fewer repetitions than SUP at T3 and T4 (-9.5 +/- 5.5 repetitions vs. -3.3 +/- 3.6 during T3, respectively, and -10.5 +/- 8.2 repetitions vs. -2.3 +/- 2.9 repetitions during T4, respectively). No differences in hormonal measures were seen between the groups. CK concentrations were significantly (P < 0.05) elevated at T3 for both groups, but continued to elevate (P < 0.05) at T4 for PL only. No significant group differences were noted for CK at any time point. Results indicate that a proprietary protein SUP consumed before and after a resistance training session significantly contributes to improvements in exercise recovery 24 and 48 h post-exercise.

Athletic Performance and Vitamin D.

Athletic Performance and Vitamin D.

Cannell JJ, Hollis BW, Sorenson MB, Taft TN, Anderson JJ.

PURPOSE:: Activated vitamin D (calcitriol) is a pluripotent pleiotropic secosteroid hormone. As a steroid hormone, which regulates more than 1000 vitamin D-responsive human genes, calcitriol may influence athletic performance. Recent research indicates that intracellular calcitriol levels in numerous human tissues, including nerve and muscle tissue, are increased when inputs of its substrate, the prehormone vitamin D, are increased. METHODS:: We reviewed the world's literature for evidence that vitamin D affects physical and athletic performance. RESULTS:: Numerous studies, particularly in the German literature in the 1950s, show vitamin D-producing ultraviolet light improves athletic performance. Furthermore, a consistent literature indicates physical and athletic performance is seasonal; it peaks when 25-hydroxy-vitamin D [25(OH)D] levels peak, declines as they decline, and reaches its nadir when 25(OH)D levels are at their lowest. Vitamin D also increases the size and number of Type II (fast twitch) muscle fibers. Most cross-sectional studies show that 25(OH)D levels are directly associated with musculoskeletal performance in older individuals. Most randomized controlled trials, again mostly in older individuals, show that vitamin D improves physical performance. CONCLUSIONS:: Vitamin D may improve athletic performance in vitamin D-deficient athletes. Peak athletic performance may occur when 25(OH)D levels approach those obtained by natural, full-body, summer sun exposure, which is at least 50 ng.mL. Such 25(OH)D levels may also protect the athlete from several acute and chronic medical conditions.

Fish consumption, omega 3 fatty acids and cardiovascular disease. The science and the clinical trials.

Fish consumption, omega 3 fatty acids and cardiovascular disease. The science and the clinical trials.

Galli C, Risé P.

Laboratory of Lipid Nutrition and Pharmacology, Department of Pharmacological Sciences, University of Milano, Via Balzaretti 9, 20133 Milano, Italy. claudio.galli@unimi.it

Fats in fish and marine animals are rich in highly unsaturated fatty acids (FA with 5 or more double bonds) of the Omega 3 series. These FA, present in aquatic animals as an adaptation to the environmental conditions, reached the human diet through the food chain, with a significant impact on nutrition, life style and cultural conditions. Studies in the 70's showed that high fish consumption is associated with better cardiovascular health and this observation was subsequently confirmed in many studies (epidemiological, cohort, case-control). The evidence is stronger for secondary prevention and when the intakes of fish or omega 3 FA are assessed, rather than just estimated. The major effects are reduction of cardiac, especially sudden, death. Underlying mechanisms concern the antiarrhythmic activities, reduction of thrombotic and inflammatory processes and of serum triacylglycerol levels. In conclusion consumption of fish and its components should be promoted on a global scale especially in the case of subjects with cardiovascular problems. Although still some issues need to be faced especially in large scale interventions (i.e. the assessment of the omega 3 fatty acid status, correlations between levels and cardiovascular indexes and bioavailability of different forms of administration), these recommendations are highly valuable.

Fish oil and the management of hypertriglyceridemia.

Fish oil and the management of hypertriglyceridemia.

Mattar M, Obeid O.

Department of Nutrition and Food Science, American University of Beirut.

Hypertriglyceridemia, regarded as one of the independent clinical markers of metabolic syndrome, is a frequently observed disorder that has been shown to be common in the Arab region. Epidemiologic and clinical trials demonstrated that omega-3 fatty acids have the potential to reduce the incidence of cardiovascular disease (CVD); one of the mechanisms by which this effect is achieved is through reducing plasma triglyceride levels. There is strong scientific evidence from human trials that omega-3 fatty acids from either fish or fish oil supplements significantly reduce blood triglyceride levels and these benefits appear to be dose-dependent. The active ingredients of fish oils include the long chain fatty acids EPA and DHA. The ideal amount of omega-3 fatty acid that should be incorporated into the diet without provoking detrimental effects on other lipid components such as decreasing HDL-C and/or increasing LDL-C has not yet been elucidated. Presently, a prescription form of omega-3 fatty acid has been approved by the United States Food and Drug Administration (USFDA) as an adjunct to the diet for the treatment of very high triglyceride levels (> or = 500 mg/dl) in adults. Patients with hypertriglyceridemia have been shown to respond well to the use of omega-3 fatty acids even when used in conjunction with statins where greater improvements in the lipid profile were found as compared to treatment with statins alone. A determinant of the responsiveness to fish oil could be attributed to the ApoE genotype of individuals.

Liquid carbohydrate/essential amino acid ingestion during a short-term bout of resistance exercise suppresses myofibrillar protein degradation.

Metabolism. 2006 May;55(5):570-7. 

Liquid carbohydrate/essential amino acid ingestion during a short-term bout of resistance exercise suppresses myofibrillar protein degradation.

Bird SP, Tarpenning KM, Marino FE.

School of Human Movement Studies, Charles Sturt University, Bathurst, NSW 2795, Australia. sbird@csu.edu.au

A number of physiological events including the level of contractile activity, nutrient status, and hormonal action influence the magnitude of exercise-induced skeletal muscle growth. However, it is not the independent action of a single mechanism, but the complex interaction between events that enhance the long-term adaptations to resistance training. The purpose of the present investigation was to examine the influence of liquid carbohydrate (CHO) and essential amino acid (EAA) ingestion during resistance exercise and modification of the immediate hormonal response on myofibrillar protein degradation as assessed by 3-methylhistidine (3-MH) excretion. After a 4-hour fast, 32 untrained young men (18-29 years) performed a single bout of resistance exercise (complete body; 3 setsx10 repetitions at 75% of 1-repetition maximum; 1-minute rest between sets), during which they consumed a 6% CHO (n=8) solution, a 6-g EAA (n=8) mixture, a combined CHO+EAA (n=8) supplement, or placebo (PLA; n=8) beverage. Resistance exercise performed in conjunction with CHO and CHO+EAA ingestion resulted in significantly elevated (P<.001) glucose and insulin concentrations above baseline, whereas EAA ingestion only increased the postexercise insulin response (P<.05). Time matched at 60 minutes, the PLA group exhibited a peak cortisol increase of 105% (P<.001) with no significant change in glucose or insulin concentrations. Conversely, the CHO and CHO+EAA groups displayed a decrease in cortisol levels of 11% and 7%, respectively. Coinciding with these hormonal response patterns were significant differences in myofibrillar protein degradation. Ingestion of the EAA and CHO treatments attenuated 3-MH excretion 48 hours after the exercise bout. Moreover, this response was synergistically potentiated when the 2 treatments were combined, with CHO+EAA ingestion resulting in a 27% reduction (P<.01) in 3-MH excretion. In contrast, the PLA group displayed a 56% increase (P<.01) in 3-MH excretion. These data demonstrate that not only does CHO and EAA ingestion during the exercise bout suppress exercise-induced cortisol release; the stimulatory effect of resistance exercise on myofibrillar protein degradation can be attenuated, most dramatically when the treatments are combined (CHO+EAA). Through an "anticatabolic effect," this altered balance may better favor the conservation of myofibrillar protein.

Upper limit of fat-free mass in humans: A study on Japanese Sumo wrestlers

Masakatsu Kondo, Takashi Abe, Ph.D, Shigeki Ikegawa, Yasuo Kawakami, Tetsuo Fukunaga

Upper limit of fat-free mass in humans: A study on Japanese Sumo wrestlers

American Journal of Human Biology, Volume 6 Issue 5, Pages 613 - 618

If limitations exist in skeletal dimensions, fat-free mass (FFM) might have an upper limit. To explore the upper limit to FFM, 37 professional Japanese Sumo wrestlers, 14 highly trained bodybuilders, and 26 untrained men were investigated for body composition (fat mass and FFM) and cross-sectional areas (CSA) of limb muscles, by hydrodensitometry and ultrasound, respectively. Mean % fat of Sumo wrestlers, bodybuilders, and untrained subjects were, respectively, 26.1%, 10.9%, and 12.1%. Sumo wrestlers had a significantly greater FFM than bodybuilders, who had a greater FFM than the untrained men. Six of the wrestlers had more than 100 kg of FFM, including the largest one of 121.3 kg (stature: 186 cm, mass: 181 kg, %fat: 33.0%). The FFM/stature ratio of elite Sumo wrestlers averaged at 0.61 kg/cm, with the highest 0.66 kg/cm. It is suggested that a FFM/stature ratio of 0.7 kg/cm may be an upper limit in humans.

Dietary Conjugated Linoleic Acid Induces Tissue-Specific Lipoprotein Lipase mRNA Modulation in High-Sucrose-Fed Mice

Dietary Conjugated Linoleic Acid Induces Tissue-Specific Lipoprotein Lipase mRNA Modulation in High-Sucrose-Fed Mice

Lyssia Castellanos-Tapiaa, Gloria Yepiz-Plasenciab, Silvia Y. Moya-Camarenaaa

Ann Nutr Metab 2009;54:131-137 (DOI: 10.1159/000210434)

  Abstract

Background/Aims: To delineate the hypotriglyceridemic effect of conjugated linoleic acid (CLA) in mice, the effect of this fatty acid on lipoprotein lipase (LPL) and apolipoprotein C-III (ApoCIII) mRNA accumulation in muscle, adipose and liver tissue was studied. Methods: CD-1 mice were housed in groups of 6 and randomized to one of three experimental diets for 3 weeks: SUC: 65% sucrose by weight; CLA: 1% CLA oil (34.4% c9,t11; 35.1% t10,c12 and 4.1% other conjugated isomers) and 65% sucrose, and DEX: 65% dextrose, as a control. Results: LPL mRNA levels in muscle tissue were increased in the DEX group and in the CLA group (240% increase) compared with the SUC group. In contrast, LPL mRNA levels were 81% lower in epididymal adipose tissue from the CLA group compared with the SUC group. There was no effect of dietary treatments on ApoCIII mRNA accumulation in the liver. Conclusions: These data suggest that dietary CLA may induce partitioning of circulating triglycerides to muscle tissue, preventing their accumulation in adipocytes

Coingestion of protein with carbohydrate during recovery from endurance exercise stimulates skeletal muscle protein synthesis in humans

Coingestion of protein with carbohydrate during recovery from endurance exercise stimulates skeletal muscle protein synthesis in humans

from Journal of Applied Physiology recent issues 

by Howarth, K. R., Moreau, N. A., Phillips, S. M., Gibala, M. J.

Coingestion of protein with carbohydrate (CHO) during recovery from exercise can affect muscle glycogen synthesis, particularly if CHO intake is suboptimal. Another potential benefit of protein feeding is an increased synthesis rate of muscle proteins, as is well documented after resistance exercise. In contrast, the effect of nutrient manipulation on muscle protein kinetics after aerobic exercise remains largely unexplored. We tested the hypothesis that ingesting protein with CHO after a standardized 2-h bout of cycle exercise would increase mixed muscle fractional synthetic rate (FSR) and whole body net protein balance (WBNB) vs. trials matched for total CHO or total energy intake. We also examined whether postexercise glycogen synthesis could be enhanced by adding protein or additional CHO to a feeding protocol that provided 1.2 g CHO·kg–1·h–1, which is the rate generally recommended to maximize this process. Six active men ingested drinks during the first 3 h of recovery that provided either 1.2 g CHO·kg–1·h–1 (L-CHO), 1.2 g CHO + 0.4 g protein·kg–1·h–1 (PRO-CHO), or 1.6 g CHO·kg–1·h–1 (H-CHO) in random order. Based on a primed constant infusion of l-[ring-2H5]phenylalanine, analysis of biopsies (vastus lateralis) obtained at 0 and 4 h of recovery showed that muscle FSR was higher (P < 0.05) in PRO-CHO (0.09 ± 0.01%/h) vs. both L-CHO (0.07 ± 0.01%/h) and H-CHO (0.06 ± 0.01%/h). WBNB assessed using [1-13C]leucine was positive only during PRO-CHO, and this was mainly attributable to a reduced rate of protein breakdown. Glycogen synthesis rate was not different between trials. We conclude that ingesting protein with CHO during recovery from aerobic exercise increased muscle FSR and improved WBNB, compared with feeding strategies that provided CHO only and were matched for total CHO or total energy intake. However, adding protein or additional CHO to a feeding strategy that provided 1.2 g CHO·kg–1·h–1 did not further enhance glycogen resynthesis during recovery.

Nutritional and contractile regulation of human skeletal muscle protein synthesis and mTORC1 signaling

Nutritional and contractile regulation of human skeletal muscle protein synthesis and mTORC1 signaling

from Journal of Applied Physiology recent issues 

by Drummond, M. J., Dreyer, H. C., Fry, C. S., Glynn, E. L., Rasmussen, B. B.

In this review we discuss current findings in the human skeletal muscle literature describing the acute influence of nutrients (leucine-enriched essential amino acids in particular) and resistance exercise on muscle protein synthesis and mammalian target of rapamycin complex 1 (mTORC1) signaling. We show that essential amino acids and an acute bout of resistance exercise independently stimulate human skeletal muscle protein synthesis. It also appears that ingestion of essential amino acids following resistance exercise leads to an even larger increase in the rate of muscle protein synthesis compared with the independent effects of nutrients or muscle contraction. Until recently the cellular mechanisms responsible for controlling the rate of muscle protein synthesis in humans were unknown. In this review, we highlight new studies in humans that have clearly shown the mTORC1 signaling pathway is playing an important regulatory role in controlling muscle protein synthesis in response to nutrients and/or muscle contraction. We propose that essential amino acid ingestion shortly following a bout of resistance exercise is beneficial in promoting skeletal muscle growth and may be useful in counteracting muscle wasting in a variety of conditions such as aging, cancer cachexia, physical inactivity, and perhaps during rehabilitation following trauma or surgery.