Obesity gene is no barrier to weight loss

People carrying a gene variant linked to weight gain can benefit from weight-loss programmes just as much as those without it, research from Newcastle University has shown.

A variant on the FTO gene is one of 97 potential gene variants considered likely to influence a person's chances of being overweight or obese. While several gene variants have been linked with obesity, FTO appears to have one of the strongest associations – people with two copies of the gene variant have been shown to weigh on average 3kg heavier than their non-FTO counterparts.

'It has become clear that genetics play a part in the reason why some of us get fatter,' said Professor John Mathers, lead author of the research from Newcastle University. 'The one that has the biggest effect in most people is the FTO gene, so we wondered whether having the [high-risk version of the] FTO gene would affect how well you could lose weight.'

The team carried out a systematic review of previously published research, focusing on eight randomised control trials. In these trials, patients were randomly allocated weight-loss programmes focusing on diet, exercise, medication or behaviour change therapy. Alongside testing how FTO-patients fared compared with non-FTO control groups, the authors investigated whether one weight-loss method was more effective than the others under investigation.

After reviewing the combined studies involving over 9000 adults, the researchers concluded that carrying the FTO gene variant did not affect the ability of patients to lose weight. This was shown to be true regardless of the weight loss programme undertaken, and none of the methods were shown to be preferable to the others – the diet-based programme was shown to be as effective as a behaviour change method.

The studies also identified that neither gender nor ethnicity affected an individual's ability to lose weight.

Dr Jude Oben, co-founder of the Obesity Action Campaign and senior lecturer in hepatology at University College London, said: 'That this size of study and its robust statistical methodologies support common sense is great. It means that general weight-loss strategies which must involve the psychological, nutritional, physical and policy changes should be developed.'

While NHS Choices acknowledges that these results 'sound like good news' and appear to suggest that all those who want to lose weight have an equal chance of success, it points out that these studies only analysed weight loss with regards to the FTO gene variant, and that it is feasible that other gene variants may have a bearing on weight loss.