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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. Patients 307 participants with a mean age of 45.5 years (SD, 9.7 years) and mean body mass index of 36.1 kg/m2 (SD, 3.5 kg/m2). Intervention A low-carbohydrate diet, which consisted of limited carbohydrate intake (20 g/d for 3 months) in the form of low–glycemic index vegetables with unrestricted consumption of fat and protein. After 3 months, participants in the low-carbohydrate diet group increased their carbohydrate intake (5 g/d per wk) until a stable and desired weight was achieved. A low-fat diet consisted of limited energy intake (1200 to 1800 kcal/d; ≤30% calories from fat). Both diets were combined with comprehensive behavioral treatment. Measurements Weight at 2 years was the primary outcome. Secondary measures included weight at 3, 6, and 12 months and serum lipid concentrations, blood pressure, urinary ketones, symptoms, bone mineral density, and body composition throughout the study. Results Weight loss was approximately 11 kg (11%) at 1 year and 7 kg (7%) at 2 years. There were no differences in weight, body composition, or bone mineral density between the groups at any time point. During the first 6 months, the low-carbohydrate diet group had greater reductions in diastolic blood pressure, triglyceride levels, and very-low-density lipoprotein cholesterol levels, lesser reductions in low-density lipoprotein cholesterol levels, and more adverse symptoms than did the low-fat diet group. The low-carbohydrate diet group had greater increases in high-density lipoprotein cholesterol levels at all time points, approximating a 23% increase at 2 years. Limitation Intensive behavioral treatment was provided, patients with dyslipidemia and diabetes were excluded, and attrition at 2 years was high. Conclusion Successful weight loss can be achieved with either a low-fat or low-carbohydrate diet when coupled with behavioral treatment. A low-carbohydrate diet is associated with favorable changes in cardiovascular disease risk factors at 2 years. Primary Funding Source National Institutes of Health.

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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. Differences between the LCD and LFD on change in outcome variables were examined with mixed linear models. Compared to the LFD, the LCD had significantly larger decreases in cravings for carbohydrates/starches and preferences for high‐carbohydrate and high‐sugar foods. The LCD group reported being less bothered by hunger compared to the LFD group. Compared to the LCD group, the LFD group had significantly larger decreases in cravings for high‐fat foods and preference for low‐carbohydrate/high‐protein foods. Men had larger decreases in appetite ratings compared to women. Prescription of diets that promoted restriction of specific types of foods resulted in decreased cravings and preferences for the foods that were targeted for restriction. The results also indicate that the LCD group was less bothered by hunger compared to the LFD group and that men had larger reductions in appetite compared to women.

This study described the relationship between amount of sleep and behavior problems among preschoolers. Participants were 510 children aged 2 to 5 years who were enrolled through 68 private pediatric practices. Parents reported on the amount of sleep their child obtained at night and in 24-hour periods. With demographic variables controlled, regression models were used to determine whether sleep was associated with behavior problems. The relationship between less sleep at night and the presence of a DSM-III-R psychiatric diagnosis was significant (odds ratio = 1.23, p = .026). Less night sleep (p < .0001) and less sleep in a 24-hour period (p < .004) were associated with increased total behavior problems on the Child Behavior Checklist; less night sleep (p < .0002) and less 24-hour sleep (p < .004) were also associated with more externalizing problems on that measure. Further research is needed to ascertain whether sleep is playing a causal role in the increase of behavior problems.

This study aimed to extend the literature by examining several psychological factors (i.e. depression, anxiety, and stress) in relation to binge eating. Data were collected via online surveys from a community sample of men and women of diverse backgrounds. The main study hypotheses were supported, indicating a unique relation between anxiety and binge eating, and between stress and binge eating, independent of the impact of depression. Gender differences are discussed. The results of this study suggest a need for a more detailed examination of negative affect in binge eating. Furthermore, the role of anxiety may be important for future research.

SummaryBackground 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 highprotein or a low-fat weight-loss diet for 24 months. Main outcomes included renal filtration (GFR) indices (serum creatinine, cystatin C, creatinine clearance); 24-hour urinary volume; albumin; calcium excretion; and serum solutes at 3, 12, and 24 months.Results Compared with the low-fat diet, low-carbohydrate high-protein consumption was associated with minor reductions in serum creatinine (relative difference, 24.2%) and cystatin C (28.4%) at 3 months and relative increases in creatinine clearance at 3 (15.8 ml/min) and 12 (20.8 ml/min) months; serum urea at 3 (14.4%), 12 (9.0%), and 24 (8.2%) months; and 24-hour urinary volume at 12 (438 ml) and 24 (268 ml) months. Urinary calcium excretion increased at 3 (36.1%) and 12 (35.7%) months without changes in bone density or clinical presentations of new kidney stones.Conclusions In healthy obese individuals, a low-carbohydrate high-protein weight-loss diet over 2 years was not associated with noticeably harmful effects on GFR, albuminuria, or fluid and electrolyte balance compared with a low-fat diet. Further follow-up is needed to determine even longer-term effects on kidney function.