UCL scientists confirm 'obesity gene' offset by healthy diet
4 March 2009
New research from UCL scientists confirms that children who carry a gene strongly associated with obesity could offset its effect by eating a low-energy density diet.
The study, published in the current issue of medical journal 'PloS ONE', is based on data from a sample of 2,275 children from the Bristol-based Children of the 90s, a long-running project following the lives of Bristol families. The findings confirm that people might be able to avoid becoming obese if they adopt a healthier diet with a low-energy density.
This is also the case for carriers of the FTO gene, the first common obesity gene to be identified in Caucasian populations. Previous studies have shown that adults with two copies of the FTO gene are on average 3kg heavier, and individuals with a single copy are on average 1.5kg heavier, than those without the gene.
Dietary energy density (DED) refers to the amount of energy consumed per unit weight of food, or number of calories per bite. A low dietary energy density can be achieved by eating lots of water-rich foods such as fruits and vegetables and limiting foods high in fat and sugar such as chocolate and biscuits.
UCL researchers, working with a team from the University of Bristol, looked at how DED affected the build-up of fat in the body over a period of three years in children aged between 10 and 13 years old. They found that children with a more energy dense diet (more calories per bite) tended to have more fat mass three years later and also confirmed that those carrying the high risk gene had greater fat mass overall. Additional findings confirm that children with a high genetic risk of weight gain can offset the effect of the gene if they eat a diet with fewer calories per bite.
Lead author Dr Laura Johnson, UCL Epidemiology and Public Health, said: "This is an important finding because it provides evidence that it's easier to eat too much energy and gain weight when your diet is packed tight with calories, so adopting a diet with more bulk and less energy per bite could help people avoid becoming obese regardless of their genetic risk. Obesity is not inevitable if your genes give you a higher risk because if you change the types of foods you eat this will help curb excessive weight gain.
"This shows that although our genetic make-up does have an influence on our health, it's certainly not the only defining factor. Those with high risk genes can, in some cases, resist their genetic lot if they alter their lifestyle in the right way - in this case, their diet."
To find out more about this research, follow the links at the top of this article.
UCL Context: UCL Epidemiology & Public Health and obesity
A team from UCL Epidemiology & Public Health, led by Prof Jane Wardle, are working on a £1.2m project with scientists from King's College London, Newcastle, Manchester, Southampton and Glasgow Universities, to improve the health of obese pregnant women and their babies. The grant has been awarded by the National Institute of Health Research (NIHR) and aims to develop a safe intervention for obese women during pregnancy which can be readily translated into clinical practice.