Overweight and obese people around the world are being conned out of billions of pounds a year by companies selling bogus health foods that do nothing to help them lose weight, a leading scientist has warned.
Michael Lean, professor of human nutrition at Glasgow University, told the Guardian that of the hundreds of slimming strategies that are actively marketed at overweight people, the only ones proven to work are low-calorie diets, exercise programmes, the drugs orlistat and sibutramine, and in some cases bariatric surgery.
In an editorial in the British Medical Journal, Lean attacks the "commercial exploitation of vulnerable patients with quack medicines" and calls for strict enforcement of new laws that have recently made it illegal for companies to mislead customers over the health benefits of their products.
Unlike medicines, which must be proved to be effective in clinical trials, the regulations around health foods are less stringent. In May this year, the UK adopted an EU directive on unfair commercial practices that was drawn up to "protect vulnerable consumers who are often the target of unscrupulous traders". The directive obliges companies not to mislead consumers with health claims for their products.
"In the past it was a case of buyer beware, but now the law has changed and it's the marketeer that has to beware. If they're using misleading marketing, they are committing a crime," Lean said.
In his article, Lean argues that despite the introduction of the new law many companies continue to mislead customers by selling foods that have no proven benefit to health.
"It is already illegal under food labelling regulations to claim that food products can treat or prevent disease. However, huge numbers of such claims are still made, particularly for obesity," he writes. In many cases, companies suggest only indirectly that a health food will help people lose weight.
"The problem is that most food companies can't be bothered to do the research and in most cases, they know the products they're selling don't do what they say," Lean told the Guardian.
Professor Lean has served as an expert on the Joint Health Claims Initiative, which criticised an advertising campaign for St Ivel Advance milk fronted by the fertility expert Robert Winston. The adverts claimed that the milk, which contains omega-3 fatty acid, might improve children's learning and concentration. The adverts were pulled following a ruling by the Advertising Standards Authority.
"The new regulations provide good legislation to protect vulnerable consumers from misleading 'health food' claims. They now need to be enforced proactively to help direct doctors and consumers towards safe, cost-effective and evidence-based management of diseases," Lean writes in his editorial. "The regulations may even help with the bigger battle to prevent obesity, by prohibiting advertisements across the EU that encourage children to buy energy-dense products or to pester their parents to buy them."
In 2000, a report from Richard Cleland at the US Federal Trade Commission estimated that $35bn (£22bn) was spent in the US alone on weight loss products, many of which were marketed with false or unsubstantiated claims, enticing 7% of the population to buy them.
