Scientists have identified the "fat" gene, which can increase the risk of an individual being overweight or obese.

Those who carry a flawed version of the "fat mass and obesity-associated" (FTO) gene, which makes the carrier crave fat-filled or sugary foods, tend to eat 100 more calories per meal per day than those without it. And all those calories can add up fast: in one week the average carrier consumes 2,100 more calories than those without - which is a whole extra day's worth of food.

However researchers in the U.K. have found that we can't completely blame the "junk food gene" for our weight problems. In a study of the eating and exercise habits of about 220,000 adults, scientists discovered that FTO carriers with an active lifestyle weakened the effects of the gene by 27 per cent, while those who didn't exercise had a 30 per cent greater chance of being obese than those who don't have a copy of the gene. Even the unlucky 14 per cent who carry two copies of the gene (and therefore have a 69 per cent higher chance of obesity than those without the gene) can still benefit from exercise: those who were active had a 40 per cent reduced chance of obesity.

While you may be tempted to find out whether or not you carry the FTO gene, health professionals warn that it may be futile to screen for obesity-related genes. Such screening could detract from the real causes of obesity since everyone should eat well and exercise, regardless of their DNA. Genetics and lifestyle choices co-determine your weight, so you can overcome your genes!