Slimming supplements are an ineffective weight loss method, a biased researcher has found after scanning the literature in the area.
Writing in the December 2010 issue of Nutrition Bulletin, Helena Gibson-Moore's mini meta analysis concluded there was insufficient evidence backing the efficacy of weight loss supplements, and therefore should not be recommended by health professionals to the overweight and obese.
She concluded that pharmaceutical interventions were more likely to yield positive results.
“Considering the wealth of evidenced-based advice and guidance available to treat overweight and obesity, dietary supplements for weight loss are unlikely to be used in the clinical setting in the near future,” she wrote, noting, “a lack of robust evidence” supporting their efficacy.
“Health professionals need to be aware of the potential safety concerns associated with their use and also advise individuals that most supplements are costly and may result in frustration and disappointment when expectations are not successfully met in the long-term.
“People who use weight-loss supplements may be highly motivated to lose weight and therefore health-care professionals should try and utilise this motivation to encourage evidence-based weight-loss approaches and the use of proven, safe, and effective treatments when embarking on weight-loss attempts.”
Nutrition Bulletin is funded by the British Nutrition Foundation, a group which counts large food manufacturers, pharma players, ingredient suppliers and retailers among its membership, including GlaxoSmithKline, Marks & Spencer, Waitrose, McDonald’s, Heinz, Yakult and Danisco.
Let the NHCR be the judge of that (slimming claims)
Responding to the findings, supplements group the UK Council for Responsible Nutrition (CRN), pointed to the EU nutrition and health claims regulation (NHCR), under which a series of weight management claims are under adjudication and due for publication at the end of the year.
“CRN agrees that lifestyle and behavioural interventions are the main approaches for successful, long term weight maintenance and weight loss,” said chairman Ric Hobby, noting the research was focused on calorie input and expenditure.
“All functional health claims, including those related to beneficial effects on body weight, sense of hunger or satiety are currently being assessed scientifically by the European Food Safety Authority (EFSA).
“A list of authorised claims will form the basis of all permitted health claims on foods and food supplement products in Europe. CRN support all regulatory developments which protect consumers’ health and interests, including the removal of false and misleading claims, and which ensure the safety and efficacy of food supplements.”
Some study details
Gibson-Moore referenced an as yet unpublished study, a summary of which was presented last summer at the 11th International Congress on Obesity in Stockholm, Sweden, which found no statistical difference in weight loss between a range of weight loss supplements and placebo among 179 overweight or obese people.
The supplements included L-carnitine, guarana seed powder, bean extract, konjac extract, polyglucosamine, cabbage powder, fibre pills, sodium alginate formulations and selected plant extracts. All were purchased at German pharmacies, with subjects receiving one of them or placebo for eight weeks.
Those on the supplements recorded weight loss of between 1-2 kilograms, while the placebo group averaged 1.2kg weight loss.
Gibson-Moore noted that when the report was publicised in the summer, the British press had responded with headlines such as ‘Weight loss supplements do not work, say experts’ (MailOnline); ‘Food supplements “make no difference for slimmers” (The Daily Telegraph 2010) and ‘Diet pills “do a fat lot of good”’ (The Sun 2010).
EFSA recently published a positive opinion linking konjac mannan (glucomannan)'s ability to support weight loss, “in the context of an energy-restricted diet”.