RANDOMIZED COMPARISON OF DIETS FOR MAINTAINING OBESE SUBJECTS WEIGHT AFTER MAJOR WEIGHT-LOSS - AD-LIB, LOW-FAT, HIGH-CARBOHYDRATE DIET V FIXED-ENERGY INTAKE

Objectives: To compare importance of rate of initial weight loss for l ong term outcome in obese patients and to compare efficacy of two diff erent weight maintenance programmes. Design: Subjects were randomised to either rapid or slow initial weight loss. Completing patients were re-randomised to one year weight maintenance programme of ad lib diet or fixed energy intake diet Patients were followed up one year later. Setting: University research department in Copenhagen, Denmark. Subjec ts: 43 (41 women) obese adults (body mass index 27-40) who were otherw ise healthy living in or around Copenhagen. Interventions: 8 weeks of low energy diet (2 MJ/day) or 17 weeks of conventional diet (5 MJ/day) , both supported by an anorectic compound (ephedrine 20 mg and caffein e 200 mg thrice daily); one year weight maintenance programme of ad li b, low fat, high carbohydrate diet or fixed energy intake diet (less t han or equal to 7.8 MJ/day), both with reinforcement sessions 2-3 time s monthly. Main outcome measures: Mean initial weight loss and proport ion of patients maintaining a weight loss of > 5 kg at follow up. Resu lts: Mean initial weight loss was 12.6 kg (95% confidence interval 10. 9 to 14.3 kg) in rapid weight loss group and 12.6 (9.9 to 15.3) kg in conventional diet group. Rate of initial weight loss had no effect on weight maintenance after 6 or 12 months of weight maintenance or at fo llow up. After weight maintenance programme, the ad lib group had main tained 13.2 (8.1 to 18.3) kg of the initial weight loss of 13.5 (11.4 to 15.5) kg, and the fixed energy intake group had maintained 9.7 (6.1 to 13.3) kg of the initial 13.8 (11.8 to 1.7) kg weight loss (group d ifference 3.5 (-2.4 to 9.3) kg). Regained weight at follow up was grea ter in fixed energy intake group than in ad lib group (11.3 (7.1 to 15 .5) kg v 5.4 (2.3 to 8.6) kg, group difference 5.9 (0.7 to 11.1) kg, P < 0.03), At follow up, 65% of ad lib group and 40% of fixed energy in take group had maintained a weight loss of > 5 kg (P < 0.07). Conclusi on: Ad lib, low fat, high carbohydrate diet was superior to fixed ener gy intake for maintaining weight after a major weight loss. The rate o f the initial weight loss did not influence long term outcome.