A high‐fibre bean‐rich diet versus a low‐carbohydrate diet for obesity. (30th April 2013) - Tonstad, S.
Abstract: Background: High‐fibre and low‐carbohydrate diets may enhance satiety and promote weight loss. We compared a diet rich in beans aiming to increase dietary fibre and promote weight loss with a low‐carbohydrate diet in a randomised controlled trial to assess effect and tolerability of the high‐fibre bean‐rich diet. Methods and results: One hundred and seventy‐three women and men, with a mean body mass index of approximately 36 kg m −2 (one‐fifth with diabetes type 2) were randomised to a high‐fibre bean‐rich diet that achieved mean (SD) fibre intakes of 35.5 (18.6) g day −1 for women and 42.5 (30.3) g day −1 for men, or a low‐carbohydrate diet. Both diets were induced gradually over 4 weeks and included a 3‐day feeding phase. Among 123 (71.1%) completers at 16 weeks, mean (SD) weight loss was 4.1 (4.0) kg in the high‐fibre versus 5.2 (4.5) kg in the low‐carbohydrate group [difference, 1.1 kg, 95% confidence interval (CI) = −2.6 to −0.5; P = 0.2], with results similar to the intent‐to‐treat population. Low‐density lipoprotein (LDL)‐cholesterol levels decreased with the high‐fibre diet (difference in LDL‐cholesterol versus low‐carbohydrate diet, 0.2 mmol L −1, 95% CI = 0.01–0.44 mmol L −1 ; P = 0.045), as did total cholesterol ( P = 0.038), whereas changes in other lipids and glucose did not differ. After 52 weeks, the low‐carbohydrate ( n = 24) group tended to retain weight loss better than the high‐fibre group ( P = 0.06), although total cholesterol remained lower with the bean‐rich diet ( P = 0.049). Conclusions: A high‐fibre bean‐rich diet was as effective as a low‐carbohydrate diet for weight loss, although only the bean‐rich diet lowered atherogenic lipids.