Weight maintenance after a very low calorie diet (VLCD) weight reduction period and the effects of VLCD supplementation. A prospective, randomized, comparative, controlled long-term trial.

OBJECTIVES

To evaluate the efficacy of a structured very low calorie diet (VLCD) weight reduction/weight maintenance behaviour programme on weight maintenance in obese patients (BMI > or = 30 kg/m2).

DESIGN

Prospective, randomized, controlled intervention trial.

SETTING

University out-patient obesity clinic.

SUBJECTS

A total of 114 obese patients from the waiting list were invited to participate in the structured weight reduction/weight maintenance programme lasting for 64 weeks. Sixty patients agreed to participate.

INTERVENTION

All 60 patients were placed on a Cambridge 330 kcal day-1 diet during the first 12 weeks. Fifty-two were subsequently randomized to either a well balanced hypocaloric diet (1600 kcal day-1), of which 220 kcal were provided by two sachets of Cambridge diet (group 1), or the same energy provided by the same principal diet (group 2) during the following 52-week weight maintenance period.

MAIN OUTCOME MEASURES

During the VLCD period, the mean body weight decreased significantly from 112.4 +/- 19.8 to 91.6 +/- 17.7 kg (P < 0.0001). Seventy-one per cent of the weight loss was fat. During the weight maintenance period the average body weight increased significantly in group 1: 8.0 +/- 8.2 vs. 12.3 +/- 9.7 kg in group 2 (P < 0.0001). After the 64-week treatment period the mean body weight in group 1 was 93.7 +/- 18.1 kg and significantly lower compared to 109.9 +/- 23.8 kg in group 2 (P = 0.008). Compliance was high: 87% completed the VLCD period and 75% completed the whole 64-week treatment programme.

CONCLUSION

Very low calorie diet as part of the dietary allowance during the weight maintenance programme partly prevents weight regain. This finding can be translated into practical treatment recommendations.