Global sales of anti-obesity medication reached a record high £600 million (US$1.2 billion) in 2005 and continue to grow. However, recent research indicates that results are far below the average of five percent of body mass weight recommended by the UK-based National Institute of Clinical Excellence (NICE).

Research found that only moderate weight loss is achieved by taking anti-obesity drugs. The results which were published in the British Medical Journal showed less than 11 pounds being the average weight lost by participants. According to Canadian researchers who reviewed 30 placebo-controlled trials, many of the adult participants will still remain overweight even after taking anti-fat medications such as sibutramine (Reductil), orlistat (Xenical) and rimonabant (Acomplia).

Professor Gareth Williams, a drugs expert at the University of Bristol said that without lifestyle changes weight loss will be even less even when using anti-obesity drugs.