Health claims 'simply not credible'
The marketing hype surrounding the vast majority of weight management ingredients "precedes or grossly outweighs the evidence" backing them, according to a leading scientist in the field.
Speaking as the European Food Safety Authority (EFSA) published draft guidance highlighting the importance of human intervention trials in supporting health claims under a new European Regulation, Unilever senior scientist Dr David Mela said much of the evidence behind these ingredients was inconsistent and "simply not credible"
Mela, who has built up an international reputation for his work on food intake and weight control, heads up the Food & Health Research Institute at Unilever, which is developing products containing the appetite suppressant hoodia gordonii with partner Phytopharm.
Addressing a nutrition and health forum organised by Leatherhead Food International, he said that the vast majority of fat blockers, appetite suppressants and other weight management ingredients currently on the market was not supported by properly controlled clinical studies, or anything even approximating sound science. "Hardly any" had the data needed to support a claim under the new Nutrition and Health Claims Regulation, he predicted.
Research methodology was dogged with errors including "faulty design and inappropriate or no controls", he added. "People are comparing fat with protein." Likewise, the active ingredient tested was frequently not representative of the end product, in terms of dose or food matrix, while there were few attempts to prove efficacy after processing or storage.
The most worrying tendency was pulling out bits of the data to support a claim by focusing on results taken at "random single time points" during a trial rather than talking about the total effect of an ingredient over the course of a trial, he said.
In vitro and other data that did "not in any way prove the efficacy" of ingredients on humans was also widely quoted in marketing materials.
Equally concerning was whether there was sufficient expertise within EFSA properly to assess the merits of human and other data supplied by ingredients companies to support claims in this area under the new Regulation, he said. "This needs specialist, multi-disciplinary expertise. If you get a collection of nutritionists [EFSA's scientific panel on dietetic products, nutrition, and allergies] to assess claims relating to satiety, well, they could make a real mess of it. They must bring in the appropriate experts and give them sufficient time to look at the evidence."
Professor John Blundell, director of the Human Appetite Research Unit at the University of Leeds and chair of the International Life Sciences Institute's Appetite Regulation task force, added: "I'm scared about this. Who are the people that will judge these claims?"
