Overweight patients told by their doctors to go to Weight Watchers lose around twice as much weight as people receiving standard weight loss care over 12 months, according to the findings of a study.
In the first randomised controlled trial to directly compare a commercial weight-loss programme with standard care by family doctors, Weight Watchers was found to be more than twice as effective.
More people stuck to the Weight Watchers diet, they lost more weight and fat mass, and also shaved more off their waist measurements than those assigned to standard care.
Susan Jebb of Britain's Medical Research Council (MRC) Human Nutrition Research Unit, who led the study, said the results showed Weight Watchers is a robust intervention that is generalisable to other economically developed countries.
Interventions to treat obesity
"This kind of research is important so that we can identify clinically effective interventions to treat obesity," she said.
The study, published in the Lancet, was funded by Weight Watchers International but run as an investigator-led trial with all data collection and analysis conducted by the independent research team.
The investigators assessed 772 overweight and obese adults in Australia, Germany and Britain. Study participants were randomly assigned to receive either 12 months of standard care as usually offered by the primary care team, or referred to and given a 12-month free membership for a Weight Watchers group in their neighbourhood.
As well as losing twice as much weight as those in the standard care group, patients referred to Weight Watchers were also more than three times as likely to lose at least 10% of their initial body weight. Some 61% of patients in the Weight Watchers group lost at least 5% of their body weight, compared with 32% in the standard care group.
More weight lost on Weight Watchers
The average weight loss at 12 months was 5.1 kg for those using Weight Watchers versus 2.2 kg for those on standard care. For those who completed the full 12 months, average weight loss was 6.7 kg on Weight Watchers versus 3.3 kg on standard care.
"These important findings show that obesity treatment is effective and structured commercial programmes can enhance outcomes," said Nick Finer, a consultant endocrinologist and bariatric physician at University College London Hospitals, who was not involved in the research.
In a commentary on the study, Kate Jolly and Paul Aveyard of the school of health and population sciences at Britain's Birmingham University said cost-effectiveness was a key factor in determining whether commercial programmes such as Weight Watchers become part of publicly funded health care.
The health of nations
They added that the low cost of these programmes makes the case for incorporation intuitively appealing.
David Kirchhoff, CEO of Weight Watchers International, said the Lancet study proves that Weight Watchers is part of the solution to help transform the health of nations.
"There is a clear need for practical treatment solutions that are proven effective, affordable and scalable to have a population-wide impact," he said. (Reuters Health, September 2011)