Nutrition

J Nutrition August, 2006

[essential amino acid intake prevents muscle loss during trauma] Interplay of Stress and Physical Inactivity on Muscle Loss: Nutritional Countermeasures J. Nutr. 2006 136: 2123-2126 D. Paddon-Jones “nactivity-mediated protein catabolism occurs in many circumstances ranging from catastrophic events such as severe illness or injury, to unique environments such as spaceflight/microgravity, to more insidious causes such as physical frailty and the progression of aging. Nevertheless, regardless of the etiology, the consequences of inactivity are readily observable and debilitating. Mechanistically, the loss of lean body mass during inactivity is the result of a chronic imbalance between muscle protein synthesis and breakdown. When inactivity is accompanied by the stress of trauma or disease, the rate of muscle protein catabolism can increase several fold. ..The prerequisite for muscle protein synthesis and the most readily adaptable stimulus is dietary-derived amino acids. This review focuses on the role of amino acid supplementation in the maintenance of skeletal muscle mass during age-related and clinically mandated inactivity.”

The Discovery of a Vitamin Role for Carnitine: the First 50 Years J. Nutr. 2006 136: 2131-2134. Carnitine is called a quasi-vitamin, because we normally make them, but with age, disease, and stress, we may require them from dietary or supplement sources. Choline is essential for adult men and is now recognized as a vitamin. Carnitine is advertised as a supplement for aid in weight loss and improved exercise performance.

[sugars from dietary fiber are important] L-Rhamnose and Lactulose Decrease Serum Triacylglycerols and Their Rates of Synthesis, but Do Not Affect Serum Cholesterol Concentrations in Men J. Nutr. 2006 136: 2160-2166 Colonic short-chain fatty acids (SCFA) may affect hepatic lipid metabolism. Lactulose increases colonic acetate production, whereas L-rhamnose increases propionate. ..We conclude that these results do not support a primary role for propionate in the cholesterol-lowering effect of soluble fiber. However, both lactulose and L-rhamnose lowered serum TG (expressed as a percentage change) and TGFA synthesis, compared with D-glucose, which increased them…”

[more variety in fruits and vegetables is better for health] Dietary Botanical Diversity Affects the Reduction of Oxidative Biomarkers in Women due to High Vegetable and Fruit Intake J. Nutr. 2006 136: 2207-2212 “…Two diets were developed that varied in botanical diversity and provided 8–10 servings of VF/d. The high botanical diversity diet (HBD) included foods from the 18 botanical families that induced a reduction in oxidative damage of lipids or DNA. The low botanical diversity diet (LBD) emphasized 5 of these botanical families based on reports that their bioactive components had high antioxidant activity…These findings indicate that botanical diversity plays a role in determining the bioactivity of high-VF diets and that smaller amounts of many phytochemicals may have greater beneficial effects than larger amounts of fewer phytochemicals.”

[olive oil protects health] The Olive Constituent Oleuropein Exhibits Anti-Ischemic, Antioxidative, and Hypolipidemic Effects in Anesthetized Rabbits J. Nutr. 2006 136: 2213-2219 ” The goal of this study was to evaluate the efficacy of the antioxidant olive constituent, oleuropein, on infarct size, oxidative damage, and the metabolic profile in rabbits subjected to ischemia. Oleuropein, 10 or 20 mg/(kg·d), was administered … Oleuropein, for 3 or 6 wk, reduced the infarct size, conferred strong antioxidant protection and reduced the circulating lipids. This is the first experimental study in vivo that suggests the possibility of using an olive constituent in the treatment of ischemia.”

[selenium protects prostate] Hemolysate Thioredoxin Reductase and Glutathione Peroxidase Activities Correlate with Serum Selenium in a Group of New Zealand Men at High Prostate Cancer Risk J. Nutr. 2006 136: 2232-2235. ” The study provides data relating serum selenium concentration to activities of 2 key selenoenzymes, hemolysate thioredoxin reductase (TR) and glutathione peroxidase (GPx), measured by spectrophotometry, in a group of men at high risk for prostate cancer. ..men participated in a randomized, double-blind, placebo-controlled selenium supplementation trial for 6 mo and received a placebo, or 200 or 400 µg of Se per day, in the form of a seleno yeast. ..After 6 mo of being on trial and with an estimated 66% of the group being supplemented with seleno yeast, the TR activity of the group increased by 80% relative to baseline…”

[Understand and avoid energy-dense foods to control weight] Dietary Energy Density Is Associated with Overweight Status among 5 Ethnic Groups in the Multiethnic Cohort Study J. Nutr. 2006 136: 2243-2248 [energy-dense foods are ones with lots of calories per serving. Fried foods, chips, and soft drinks are very energy-dense foods. (Note diet drinks are not energy-dense, but they also are associated with being overweight. ) High fiber fruits and vegetables are nutrient-rich foods] ” Differences in BMI among ethnic groups may be partially explained by the consumption of energy-dense foods, which influences energy intake in controlled laboratory studies. However, the role of dietary energy density (ED, kJ/g) in free-living persons is less understood. Our objective was to determine whether ED is related to current BMI and the risk for overweight and obesity and whether these relations are consistent among ethnic groups…Our findings suggest that consumption of an energy dense diet is a risk factor for higher BMI in both men and women across ethnic groups.”

[regular information about nutrition reduces weight and cholesterol] Fiber Intakes and Anthropometric Measures are Predictors of Circulating Hormone, Triglyceride, and Cholesterol Concentrations in the Women’s Health Trial J. Nutr. 2006 136: 2249-2254. ” The unhealthy eating patterns and obesity among women in the U.S. are indicated by changes in biomarkers, such as insulin, lipoproteins, and estradiol, that are risk factors for breast cancer and cardiovascular diseases. This article models the inter-relations among diet, serum insulin, estradiol, and sex hormone binding globulin (SHBG) concentrations, plasma LDL and HDL cholesterol, and net triglyceride concentrations, using the data at baseline and 12 mo on 379 and 615 postm enopausal women in the Control and Intervention groups, respectively, of the Women’s Health Trial: Feasibility Study in Minority Populations. Subjects in the Intervention group received detailed advice over a period of 1 y for reducing fat intakes and increasing the consumption of whole grains and fruits and vegetables. The main findings were that there were significant differences between the Control and Intervention groups in the changes from baseline to 12 mo in LDL and HDL cholesterol and SHBG concentrations. Second, using a comprehensive random effects modeling framework, the ratio of fiber to energy intake was significantly associated (P < 0.05) with lower insulin and triglyceride levels, and with a higher HDL cholesterol concentration in the Intervention group. Third, the subjects’ waist-to-hip ratio and BMI were significantly associated with insulin, SHBG, LDL and HDL cholesterol, and triglyceride concentrations. Fourth, insulin levels were significantly negatively associated with SHBG and HDL cholesterol, and positively associated with LDL cholesterol, triglyceride, and estradiol concentrations. Overall, weight loss, especially around the waist, and increased fiber intakes are likely to be beneficial for lipid, cholesterol, and hormone profiles of U.S. women.”

Reply to Chow [Grape Powder Polyphenols] J. Nutr. 2006 136: 2273. This letter provides an analysis of what is in grapes that makes them so beneficial for health – as grapes, grape powder, juice (without high fructose corn syrup), and wine. Grapes with the water removed are about 90% sugars glucose and fructose, and 0.58% polyphenols (the good stuff that makes fruits and vegetables colored and healthful). Flavanols are the major flavonoids, followed by anthocyhanins, and stilbenes, especially resveratrol. Resveratrol is one of the most exciting molecules being studied by nutrition researchers because of its extremely beneficial properties.)