Presenter and journalist Jane Moore.
NHS has spent nearly £4 million since 2007 on referring patients to Weight Watchers, reveals Channel 4 Dispatches.
The programme airing tonight (Monday 28th January at 8pm) also hears from a leading academic who urges caution over the results of some of the clinical evidence relied upon to demonstrate the effectiveness of Weight Watchers for long term weight loss.
NHS referring patients to Weight Watchers
Britain is in the midst of an obesity crisis. The government wants the nation to start losing weight by 2020. But the NHS is struggling to find answers, offering everything from exercise classes to gastric bands.
In 2006, guidelines were produced for safe weight loss on the NHS - Weight Watchers diet scheme satisfied the eight point criteria, so people can now be referred to Weight Watchers by their GP.
Channel 4 Dispatches sent Freedom of Information requests to all 152 Primary Care Trusts in England - and from the 113 that replied, we calculated that the NHS has spent nearly £4 million pounds on Weight Watchers since 2007.
It's a billion pound business, but do Weight Watchers products deliver value for money?
In the UK every year 2 million of us turn to Weight Watchers for help. In turn, we helped Weight Watchers International's revenues grow to £1.2 billion pounds in 2011.
It's the biggest diet company in the world, owned by private equity firm the Artal Group.
The latest glossy Weight Watchers advert stars the glamorous, Patsy Kensit - describing how it's changed her life for the better.
Caution Over Clinical Evidence
Channel 4 Dispatches looked for clinically proven long term weight loss, and found a page on the Weight Watchers website, listing studies that have been done into Weight Watchers effectiveness.
We turned to the Centre for Evidence Based Medicine at Oxford University, and asked Claire Friedemann to analyse these studies.
However, Claire could only access 10 out of the 82 studies on the Weight Watchers website, making it hard to fully investigate their claim.
Claire Friedemann says: "Going through the university I was able to get hold of a good number of them, but ones where we didn't have a subscription, you had to pay, I couldn't get hold of them, and so if a member of the public was trying to look up these papers they might not even have the level of access that I did."
From the evidence she could access, the short term results seemed good.
Claire Friedemann says: "To twelve weeks the results were quite positive, most of the participants at least lost weight. Up to a year the participants started to have some weight regain. There were two papers that followed up their participants to 5 years and what was found in these papers was that although some of the Weight loss was maintained, in some cases over 75% of it was regained."
She urged caution with the results of the five year studies - because the participants were lifetime Weight Watchers members - the most successful dieters - who self reported their weight.
Claire Friedemann says: "So it's possible that they did not accurately measure themselves, or they may feel that they have regained too much weight after they had reached their target, and so maybe want to say that they don't actually weight as much as they do, and then this biases the results that the study found.
Another note of caution from her analysis: Weight Watchers International partly funded six of the ten studies.
Claire Friedemann says: "The danger with companies funding their own research is that they may only publish results which are positive for them"
Weight Watchers told the programme:
"Weight Watchers has a transparent and credible approach to science... We work with world-renowned obesity researchers who run independent studies.
The access to any articles or papers...within a scientific journal is governed by the publisher's copyright restrictions. Weight Watchers involvement in any study is always disclosed. Any research that is carried out using Weight Watchers methodology is of high quality and wouldn't have been accepted by scientific journals if it didn't hold up to the highest standards of scientific rigour
Weight Watchers also say:
"Evidence from published papers demonstrates that the majority of those who lose weight with Weight Watchers help do not regain it after the programme ends."
Weight Watchers: How They Make Their Millions - Channel 4 Dispatches, Monday 28th January at 8pm