Weight maintenance over 12 months after weight loss resulting from participation in a 12-week randomised controlled trial comparing all meal provision to self-directed diet in overweight adults

Background: The results of weight maintenance after initial weight loss are reported infrequently, although, when they have been reported, the outcomes are generally poor and weight regain is common. Methods: After an initial 12-week randomised intervention comparing all meal provision against a self-directed energy restriction, participants re-consented to participate in a follow-on study. Participants were given the option to choose to continue with the same dietary intervention (either all meal provision (provided free of charge) or self-directed diet) or change to the other diet for a further 12 weeks. Participants were followed up at 4-weekly intervals during both intervention periods (a total of 24 weeks), with a final follow up at 12 months. Results: Eighty-five out of 86 individuals who completed the original 12-week randomised phase chose to continue on to the follow-up study. No significant differences in further weight loss between groups (P = 0.138) [mean (SEM): -3.4% (1.1%) for all meal provision only; -3.4% (0.6%) self-directed then all meal provision; -1.1% (1.2%) all meal provision then self-directed] were seen after a further 12 weeks. Meal provision for a total of 24 weeks resulted in 67% of individuals losing at least 10% body weight. The groups switching from self-directed dieting to meal provision (or vice versa) were the only groups to have a lower mean weight at 12 months than at the start of the follow-on study. Conclusions: Structured support for 24 weeks followed by 28 weeks of self-care can result in weight maintenance, with initial weight loss maintained at 12 months from enrolling on a 12-week weight loss intervention, with a 12-week follow-on period.