Use of low-carbohydrate, high-protein diets among Americans: Correlates, duration, and weight loss

Context: Although low-carbohydrate, high-protein (LCHP) diets reemerged as popular diets, there are scant data on patterns of use in the general US population. Objective: We examined the prevalence of reported LCHP diet use (eg, Sugar Busters, The Zone, The Carbohydrate Addict's Diet, The Atkins Diet), associated weight control behaviors, diet duration, and amount of weight loss while on the diet. Design: Population-based cross-sectional survey. Setting: Telephone survey of US adults conducted from September 2002 to December 2002 (N = 9300). Main outcome measures: We used multivariable logistic regression models to determine predictors of current LCHP diet use. Results: At the time of the survey, 12.5% of Americans reported ever using a LCHP diet, and 3.4% reported current use. Prevalence of current use was similar across sex, race/ethnicity, and education levels. Among those trying to lose weight (n = 3790), 5.9% reported currently using an LCHP diet. Among current users, mean weight loss was 18.3 (median, 11.7) lb, with 18.2% reporting ≥ 30 lb weight loss, 34.0% ≥ 20 lb weight loss, and 8.8% no weight loss. More men thanwomen reported a duration of use of more than 12 months (42.2% vs 29.6%, P = .04) and median duration was greater in men than women (5.7 vs 2.8 months, P = .08). Among those trying to control weight, a significantly higher proportion of current LCHP diet users reported eating fewer calories and meeting physical activity recommendations (38.0%) compared with nonusers (29.8%). Conclusions: LCHP diets were equally prevalent across sociodemographic subgroups and many users reported significant weight loss. Approximately 40% of male users and 30% of female users reported long-term use of the diet, suggesting that for some, this dietary approach may be well tolerated.