The genetic predisposition to obesity due to the 'fat mass and obesity associated' (FTO) gene can be substantially reduced by living a physically active lifestyle according to new research by a large international collaboration, led by Ruth Loos from the Medical Research Council Epidemiology Unit, in Cambridge, UK, and published in this week's PLoS Medicine. The researchers found that the effect of the FTO gene on obesity risk is nearly 30% weaker among physically active than in physically inactive adults.
I see 2 ways to spin this: First, hey great news. Your gene report mentions that exercise will cancel some of the risk from having this weight gene.So you aren't destined to become massively obese. No need to be a victim of genetic determinism. What good news. Right?
But there's a way different way to spin this: Your gene report just came back and it says turn off the TV! Get your lazy butt of the couch NOW! Get up, put on your jogging clothes and go run 10 miles. Your genetic report says you've got to be treated like someone in boot camp. So put on a full pack and start running. Make that 20 miles. Then lift weights until you barf. Its either that or some day you are going to weigh so much you won't be able to get out of bed.
This finding holds an important public health message relevant to health care professionals and the wider public as it challenges the widely-held view that obesity 'is in my genes' and not amenable to lifestyle changes. On the contrary, this study shows that even those genetically predisposed can reduce their risk of becoming obese by being physically active.
The authors performed a comprehensive literature search and invited all researchers who had reported on the FTO gene in the past to participate in their study. They used an extensive and innovative methodology to analyze data from over 218,000 adults, to show that, in general, carrying a copy of the FTO gene increases the risk of becoming obese. However, the effect of the FTO gene on obesity risk was 27% less pronounced in individuals who were physically active (1.22 fold) compared with those who were physically inactive (1.30 fold).