New research suggests that people who are at an increased risk of developing obesity, due to their genetic makeup, can significantly reduce this risk by exercising.

Scientists based at the Medical Research Councils (MRC) Epidemiology Unit at Cambridge, UK, looked at 12 different genetic markers linked to increased body mass index (BMI) and risk of obesity in over 20,000 people from Norfolk, and assessed the impact of exercise on their outcome.  

The researchers concluded that 'genetic predisposition to increased BMI and obesity is attenuated by a physically active lifestyle'.      

Dr Ruth Loos, leader of the study, told The Telegraph that 'Our research proves that even those who have the highest risk of obesity from their genes can improve their health by taking some form of daily physical activity'. 

'People don't have to run marathons to make a difference either. Walking the dog or working in the garden all counts', Dr Loos also told The Daily Mail.   

This led to a glut of tabloid headlines declaring that the 'Genetic excuse for obesity 'is a myth'', which included The Daily Mail and The Telegraph.

But the authors pointed out that 'physical activity was measured by a self-administered physical activity questionnaire, which is less accurate than other objective instruments'.

The authors, however, concluded that their finding of a '40 per cent reduction in the genetic predisposition to common obesity is an important observation for public health'.  

The research is published in the journal PLoS Medicine.