Diet, Carbohydrate-Restricted

A key determinant of the relationship between diet and longevity is the balance of protein and carbohydrate in the diet. Eating excess protein relative to carbohydrate shortens lifespan in solitary insects. Here, we investigated the link between high-protein diet and longevity, both at the level of individual ants and colonies in black garden ants, Lasius niger. We explored how lifespan was affected by the dietary protein-to-carbohydrate ratio and the duration of exposure to a high-protein diet.

OBJECTIVES: The objective of this prospective, single-site, 2-year dietary intervention study was to evaluate the effects of moderate weight reduction and subsequent partial weight regain on cardiovascular structure and function. BACKGROUND: Obesity is associated with adverse cardiac and vascular structural and functional alterations. METHODS: Sixty obese subjects (age 46 + or - 10 years, body mass index 37 + or - 3 kg/m(2)) were evaluated during their participation in a weight loss study.

BACKGROUND: Previous studies comparing low-carbohydrate and low-fat diets have not included a comprehensive behavioral treatment, resulting in suboptimal weight loss. OBJECTIVE: To evaluate the effects of 2-year treatment with a low-carbohydrate or low-fat diet, each of which was combined with a comprehensive lifestyle modification program. DESIGN: Randomized parallel-group trial. (ClinicalTrials.gov registration number: NCT00143936) SETTING: 3 academic medical centers.

This prospective study tested whether (a) baseline outcome expectations regarding the benefits of a weight-loss diet, (b) 6-month outcome realizations regarding perceived benefits actually experienced, and/or (c) the interaction between them predicted 6-12-month weight regain among overweight/obese women randomized to one of four popular weight-loss diets (N=311).

The study objective was to evaluate the effect of prescribing a low-carbohydrate diet (LCD) and a low-fat diet (LFD) on food cravings, food preferences, and appetite. Obese adults were randomly assigned to a LCD (n = 134) or a LFD (n = 136) for 2 years. Cravings for specific types of foods (sweets, high-fats, fast-food fats, and carbohydrates/starches); preferences for high-sugar, high-carbohydrate, and low-carbohydrate/high-protein foods; and appetite were measured during the trial and evaluated during this secondary analysis of trial data.

BACKGROUND AND OBJECTIVES: Concerns exist about deleterious renal effects of low-carbohydrate high-protein weight loss diets. This issue was addressed in a secondary analysis of a parallel randomized, controlled long-term trial. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Between 2003 and 2007, 307 obese adults without serious medical illnesses at three United States academic centers were randomly assigned to a low-carbohydrate high-protein or a low-fat weight-loss diet for 24 months.

Previous research shows diminished weight loss success in insulin-resistant (IR) women assigned to a low-fat (LF) diet compared to those assigned to a low-carbohydrate (LC) diet. These secondary analyses examined the relationship between insulin-resistance status and dietary adherence to either a LF-diet or LC-diet among 81 free-living, overweight/obese women [age = 41.9 ± 5.7 years; body mass index (BMI) = 32.6 ± 3.6 kg/m(2)]. This study found differential adherence by insulin-resistance status only to a LF-diet, not a LC-diet.

OBJECTIVE: The effect of weight loss on obesity-associated endothelial dysfunction is not clear because of conflicting data, demonstrating both improvement and no change in endothelial function after weight loss in obese subjects. A 2-year prospective study (n = 121) was conducted to examine: (1) the effect of obesity and weight loss (either a low-carbohydrate or and low-fat diet) on flow mediated vasodilatation (FMD), a measure of endothelial function.

Phytosterols reduce cholesterol absorption and low-density lipoprotein cholesterol concentrations, but the quantity and physiological significance of phytosterols in common diets are generally unknown because nutrient databases do not contain comprehensive phytosterol data. The primary aim of this study was to design prototype phytosterol-deficient and high-phytosterol diets for use in controlled feeding studies of the influence of phytosterols on health. A second aim was to quantify the phytosterol content of these prototype diets and three other diets consumed in the United States.

BACKGROUND: There is evidence that reducing blood glucose concentrations, inducing weight loss, and improving the lipid profile reduces cardiovascular risk in people with type 2 diabetes. OBJECTIVE: We assessed the effect of various diets on glycemic control, lipids, and weight loss. DESIGN: We conducted searches of PubMed, Embase, and Google Scholar to August 2011.