Participants in the commercial program – in this study Weight Watchers – lost twice as much weight as did those in the standard care group – an average of 5.06kg for those in the commercial program versus 2.25kg for those receiving standard care.
The study, published in The Lancet today, tracked 772 overweight and obese adults in Australia, Germany and the UK, with the Australian arm of the research led by Professor Ian Caterson from the University of Sydney.
"Our research showed Weight Watchers programs work well for those who are overweight and obese, but I was also surprised at how well our doctors do,"said Professor Caterson, Director of the Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders.
"This is the first multi-country, randomised, comparative study to show the effectiveness of commercial weight loss programs, as well as weight loss programs administered by primary health carers,"Professor Caterson said.
Participants in the commercial program were three times more likely to lose five per cent of their body weight than in the standard care group. As well as losing more weight participants in the commercial program had significantly greater improvements in insulin levels and in ratios of ‘good’ and ‘bad’ cholesterol.
Both groups recorded small reductions in blood pressure, though the differences between the two groups were not significant.
Participants in the standard care group reported one appointment per month with their health-care provider, whereas those in the commercial program attended three meetings per month in the UK and Australia, and two meetings per month in Germany.
"The greater level of contact, the more frequent opportunities to be weighed, the peer support and the access to information and resources such as recipes that those in the Weight Watchers program had could have been significant factors,"said Professor Caterson.
"We will be carrying out follow-up assessments at 18 and 24 months. Further research will examine the relative cost effectiveness of different treatment approaches,"he noted.