If, like me, you have good intentions for your body, but the willpower of a lemming, there is good news, sort of. A recent study published in the Journal of the American Medical Association shows that being slightly overweight can extend life rather than shorten it, so you don't need to feel quite so bad about that extra layer of insulation. However, if you're overweight you're still at risk of more diseases than your slim counterparts, so it looks like you'll have to choose: an earlier death and a slim physique, or live longer, be fat and get heart disease. Confused? Aren't we all.

That's not the only bit of diet news that runs contrary to conventional wisdom. We've also learnt we only need three minutes a week of exercise to stay fit and that fructose, the supposedly "good" sugar derived from fruits, can trigger overeating.

The food IQ survey, backed by the Department of Health's Change4Life campaign, came out this week, showing the majority of us don't know what makes up a healthy diet, with 77 per cent of the 2000 people surveyed scoring just 50 per cent or less.