Effect of capsaicin on substrate oxidation and weight maintenance after modest body-weight loss in human subjects

The aim of the present study was to investigate whether capsaicin assists weight maintenance by limiting weight regain after weight loss of 5 to 10 %. In this randomized double-blind placebo-controlled study, ninety-one moderately overweight subjects were randomly assigned to an intensive group that underwent all the measurements, and an extensive group that underwent the same measurements except the metabolism measurements. After a 4-week very-low-energy diet (VLED) intervention, a 3-month weight-maintenance period followed. During weight maintenance, subjects were divided into a capsaicin (135 mg capsaicin/d) and a placebo group. Body mass was measured before and after the VLED and after 1, 2 and 3 months of weight maintenance. The mean body-mass loss during the VLED was 6·6 (SD 2·0) kg (7·8 (SD 1·8) % initial body mass), and was not different between the subsequent treatment and placebo group. During weight maintenance, mean % regain during treatment was not significantly different compared with placebo (33·3 (SD 35·7) v. 19·2 (SD 41·8) %, P0·09). RQ was significantly less increased during weight maintenance in the treatment group compared with placebo (0·04 (SD 0·06) v. 0·07 (SD 0·05), P,0·05), indicating a relatively more sustained fat oxidation. Fat oxidation (g/h) after weight mainten-ance was higher in the capsaicin group compared with placebo (4·2 (SD 1·1) v. 3·5 (SD 0·9), P,0·05). These results indicate that capsaicin treatment caused sustained fat oxidation during weight maintenance compared with placebo. However, capsaicin treatment has no limiting effect on 3-month weight regain after modest weight loss. Appetite: Energy expenditure: Fat oxidation The increasing incidence of obesity is a recognized medi