Nutrition

BACKGROUND/OBJECTIVES: The contemporary American diet figures centrally in the pathogenesis of numerous chronic diseases--'diseases of civilization'--such as obesity and diabetes. We investigated in type 2 diabetes whether a diet similar to that consumed by our pre-agricultural hunter-gatherer ancestors ('Paleolithic' type diet) confers health benefits. SUBJECTS/METHODS: We performed an outpatient, metabolically controlled diet study in type 2 diabetes patients...

Over the past 20 y, higher-protein diets have been touted as a successful strategy to prevent or treat obesity through improvements in body weight management. These improvements are thought to be due, in part, to modulations in energy metabolism, appetite, and energy intake. Recent evidence also supports higher-protein diets for improvements in cardiometabolic risk factors. This article provides an overview of the literature that explores the mechanisms of action after acute protein consumption and the clinical health outcomes after consumption of long-term, higher-protein diets...

The finding that people who eat the most whole grains have a lower risk of cardiovascular disease and diabetes, compared with those who eat the least, is one of the most consistent findings in nutritional epidemiology. However, criteria for reporting whole-grain intake have varied widely, making it difficult to precisely explore the relation of whole grains and grain components with health outcomes. To enable better understanding of the health benefits of whole grain-rich diets, we propose that both observational and intervention studies should as far as possible be required to report as follows when describing whole grains: 1) quantify the amount of whole grain in the food or product in grams on a dry-weight basis, 2) describe the whole-grain definition used, 3) report and separate the different types of grains used, 4) if possible, report the structure of the grains (intact, crushed, partially milled) in foods, and 5) describe the main types of products used and processes used to make them...

PURPOSE OF REVIEW: The purpose of this study is to discuss the involvement of bone and morphogenetic proteins (BMPs) in the control of muscle mass. RECENT FINDINGS: The transforming growth factor-beta (TGFβ) superfamily comprises a large number of secreted proteins that regulate a variety of fundamental biological processes. Sequence similarities define two ligand subfamilies: the TGFβ/Activin subfamily and the BMP subfamily. Within the members of TGFβ subfamily, myostatin emerged as the most critical ligand that affects muscle size and function...

PURPOSE OF REVIEW: We provide an update on the recent advances in nutrition research regarding the role of protein intake in the development and treatment of sarcopenia of aging. RECENT FINDINGS: Specific muscle mass, strength and function cut-points for the diagnosis of sarcopenia have been identified. There is mounting evidence, as highlighted by multiple consensus statements, that the Recommended Dietary Allowance (0.8 g/kg body weight) may be inadequate to promote optimal health in older adults...

PURPOSE OF REVIEW: The literature on the influence of dietary omega-3 polyunsaturated fatty acid (ω-3 PUFA) on brain aging has grown exponentially during the last decade. Many avenues have been explored but no global picture or clear evidence has emerged. Experimental studies have shown that ω-3 PUFA is involved in many neurobiological processes that are involved in neurotransmission and neuroprotection, indicating that these PUFAs may prevent age-related brain damage. Human studies have revealed only a weak link between ω-3 PUFA status and cognitive aging, whereas interventional studies have yet to confirm it...

OBJECTIVE: Increases in childhood obesity correspond with shifts in children's snacking behaviors and food portion sizes. This study examined parents' conceptualizations of portion size and the strategies they use to portion snacks in the context of preschool-aged children's snacking. METHODS: Semi-structured qualitative interviews were conducted with non-Hispanic white (W), African American (AA), and Hispanic (H) low-income parents (n = 60) of preschool-aged children living in Philadelphia and Boston...

Performance in many sports is at least partially dependent on motor control, coordination, decision-making, and other cognitive tasks. This review summarizes available evidence about the ingestion of selected nutrients or isolated compounds (dietary constituents) and potential acute effects on motor skill and/or cognitive performance in athletes. Dietary constituents discussed include branched-chain amino acids, caffeine, carbohydrate, cocoa flavanols, Gingko biloba, ginseng, guarana, Rhodiola rosea, sage, L-theanine, theobromine, and tyrosine...

Although reviews of the association between polyphenol intake and cognition exist, research examining the cognitive effects of fruit, vegetable, and juice consumption across epidemiological and intervention studies has not been previously examined. For the present review, critical inclusion criteria were human participants, a measure of fruit, vegetable, or 100% juice consumption, an objective measure of cognitive function, and a clinical diagnosis of neuropsychological disease. Studies were excluded if consumption of fruits, vegetables, or juice was not assessed in isolation from other food groups, or if there was no statistical control for education or IQ...

The portion size of foods and beverages offered at meals has been shown to significantly affect human food intake. While portion size effects appear to be fairly robust across studies in adults, findings from studies in children are generally more variable and do not reliably predict a significant portion size effect. Eating behaviors are still forming at a young age and individual differences in children's response to portion size will depend upon genetic predisposition interacting with the child's environment...

The implications of sleep for morality are only starting to be explored. Extending the ethics literature, we contend that because bringing morality to conscious attention requires effort, a lack of sleep leads to low moral awareness. We test this prediction with three studies. A laboratory study with a manipulation of sleep across 90 participants judging a scenario for moral content indicates that a lack of sleep leads to low moral awareness. An archival study of Google Trends data across 6 years highlights a national dip in Web searches for moral topics (but not other topics) on the Monday after the Spring time change, which tends to deprive people of sleep...

The popularity of natural bodybuilding is increasing; however, evidence-based recommendations for it are lacking. This paper reviewed the scientific literature relevant to competition preparation on nutrition and supplementation, resulting in the following recommendations. Caloric intake should be set at a level that results in bodyweight losses of approximately 0.5 to 1%/wk to maximize muscle retention. Within this caloric intake, most but not all bodybuilders will respond best to consuming 2.3-3.1 g/kg of lean body mass per day of protein, 15-30% of calories from fat, and the reminder of calories from carbohydrate...

Bangladesh, the eighth most populous country in the world with about 153 million people, has recently been applauded as an exceptional health performer. In the first paper in this Series, we present evidence to show that Bangladesh has achieved substantial health advances, but the country's success cannot be captured simplistically because health in Bangladesh has the paradox of steep and sustained reductions in birth rate and mortality alongside continued burdens of morbidity. Exceptional performance might be attributed to a pluralistic health system that has many stakeholders pursuing women-centred, gender-equity-oriented, highly focused health programmes in family planning, immunisation, oral rehydration therapy, maternal and child health, tuberculosis, vitamin A supplementation, and other activities, through the work of widely deployed community health workers reaching all households...

Omega-3 and n-6 fatty acids are biosynthetic precursors to lipid mediators with antinociceptive and pronociceptive properties. We conducted a randomized, single-blinded, parallel-group clinical trial to assess clinical and biochemical effects of targeted alteration in dietary n-3 and n-6 fatty acids for treatment of chronic headaches. After a 4-week preintervention phase, ambulatory patients with chronic daily headache undergoing usual care were randomized to 1 of 2 intensive, food-based 12-week dietary interventions: a high n-3 plus low n-6 (H3-L6) intervention, or a low n-6 (L6) intervention...

Adipose tissue is no longer considered to be an inert tissue that stores fat. This tissue is capable of expanding to accommodate increased lipids through hypertrophy of existing adipocytes and by initiating differentiation of pre-adipocytes. Adipose tissue metabolism exerts an impact on whole-body metabolism. As an endocrine organ, adipose tissue is responsible for the synthesis and secretion of several hormones. These are active in a range of processes, such as control of nutritional intake (leptin, angiotensin), control of sensitivity to insulin and inflammatory process mediators (tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), resistin, visfatin, adiponectin, among others) and pathways (plasminogen activator inhibitor 1 (PAI-1) and acylation stimulating protein (ASP) for example)...

The purpose of this review is to provide a comprehensive update of epidemiologic studies that have assessed the association between sleep and obesity risk. Data suggest that short sleep is associated with an increased risk for being or becoming overweight/obese or having increased body fat. Late bedtimes are also a risk factor for overweight/obesity. Findings also suggest that changes in eating pathways may lead to increased body fat. Future experimental studies are needed to enhance our understanding of the underlying mechanisms through which sleep may play a role in the development and maintenance of childhood obesity...

No abstract text is available yet for this article.

It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of foods and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This updated position paper couples a rigorous, systematic, evidence-based analysis of nutrition and performance-specific literature with current scientific data related to energy needs, assessment of body composition, strategies for weight change, nutrient and fluid needs, special nutrient needs during training and competition, the use of supplements and ergogenic aids, nutrition recommendations for vegetarian athletes, and the roles and responsibilities of the sports dietitian...

Rates of obesity and insulin resistance have climbed sharply over the past 30 years. These epidemics are temporally related to a dramatic rise in consumption of fast food; until recently, it was not known whether the fast food was driving the obesity, or vice versa. We review the unique properties of fast food that make it the ideal obesigenic foodstuff, and elucidate the mechanisms by which fast food intake contributes to obesity, emphasizing its effects on energy metabolism and on the central regulation of appetite...