Overweight and obese patients who were referred to Weight Watchers lost twice as much weight as those who received standard care in general practice, a study in The Lancet has shown.

A total of 772 adults, with a BMI 27-35 kg/m² and at least one additional risk factor for obesity-related disease, were recruited from primary care practices in the UK, Australia and Germany. The study was a parallel group, non-blinded, randomised controlled trial.

Just under half, 377 patients, were assigned to 12 months’ free membership of Weight Watchers of whom 230 (61%) completed the programme. The Weight Watchers’ programme promoted a hypoenergetic balanced diet, increased physical activity and group support. The remaining 395 were assigned to standard care for a year which comprised advice on weight loss from a primary care health professional and treatment according to national guidelines. In this group, 214 (54%) completed the programme.

Of those patients who completed the 12-month programme, those attending Weight Watchers lost a mean of 6.7 kg compared with 3.3 kg in the standard care group. Participants in the commercial programme were also three times more likely to lose ≥5% of their initial weight than those receiving standard GP care.

Furthermore, the authors noted that the greater weight loss in those assigned to Weight Watchers was accompanied by larger reductions in waist circumference and fat mass than in those assigned to standard care, which would be expected to lead to a reduction in risk for type 2 diabetes and cardiovascular disease.

The authors concluded that a commercial weight loss programme that provides regular weighing, advice about diet and physical activity, motivation, and group support could offer a clinically useful early intervention for weight management in overweight and obese people.

Since such commercial weight loss programmes are relatively cheap (£50-£60 for 12 weeks) an accompanying editorial suggests that healthcare systems should fund patients to attend such schemes.¹

However, as with all weight loss programmes it is important to know if the weight loss achieved is maintained in the long term and produces sustainable changes in behaviour.

There is increasing emphasis on the primary care management of obesity and this is gradually gaining more emphasis in the QOF. It is unclear how cost effective this approach would be compared with a structured programme delivered in primary care either as part of the QOF or a directed/local enhanced service.

Dr Peter Savill

• Jebb SA, Ahern AL, Olson AD et al. Primary care referral to a commercial provider for weight loss treatment versus standard care: a randomised controlled trial. Lancet 2011; 378 (9801):1485-92