2 November 2011

Screening for the “obesity gene” would be ineffective and the battle against obesity should focus on society-wide action like banning junk food advertising, according to a University of Queensland researcher.

Dr J. Lennert Veerman, of the School of Population Health, commenting in PLoS Medicine on a study showing physical activity reduces the effect of the “obesity gene”, said while the logical implication would be screening, it may not be of much value.

“Testing for genetic traits that are associated with obesity makes no difference in the advice to overweight persons: increased physical activity and a healthy diet are indicated regardless of the genes,” Dr Veerman said.

He said a focus on individual genetic traits stigmatised individuals and was “a mere distraction”.

“It reinforces the popular view of obesity as a problem that individuals have to deal with, rather than one that requires societal action," he said.

“While we continue to focus on individuals, the epidemic continues to go on.”

Dr Veerman said removing ads for junk food, particularly those aimed at children, taxing high calorie foods and banning sugary drinks in school tuck shops were examples of public health actions that would be more effective.

“Before rushing to screening programs, some critical reflection on the role and risks of genetic screening for susceptibility to behavioural risk factors is warranted,” he added.

Dr Veerman said there were at least four reasons why screening individuals for genes that predispose to obesity made little clinical sense and may even do harm.

“Genetic screening for obesity has limited predictive power, is unlikely to inform therapeutic
decisions, does not add to body mass index (BMI) as predictor of disease and may distract from the societal changes that most experts think are needed to reduce the prevalence of obesity,” he said.

PLoS Medicine paper online - http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1001116

Media: Marlene McKendry, 07 3346 4713, mobile 0401 996 847.