Have you heard the one about the middle-aged, overweight bloke who ran the London Marathon in three hours flat?

No, me neither. As a large study recently proved, the idea that you can be 'fat but fit' is just another in a long line of myths attached to the health industry. The study of 3.5 million Britons' health records between 1995 and 2015 found that excess fat increases the risk of suffering heart disease by half – even when blood pressure and cholesterol levels are normal. Obese people were also seven percent more likely to suffer a stroke.

A second study, released this week, has reiterated these findings. A research team, led by academics Imperial College London and Cambridge University, looked at more than half a million Europeans and concluded that those who were overweight were more likely to develop coronary heart disease by 28pc.

To this list of risks we can add a roll call of diseases that you don't want to mess with: type 2 diabetes; gallbladder disease; osteoarthritis; cancer of the breast, colon, gallbladder, kidney, and liver. Essentially, your chances of dying from anything other than a wasp sting or a fall down the stairs are higher if you are fat – and yet, as a nation, we seem to have accepted the notion that it's OK to be obese. In the UK a staggering 67pc of adults are overweight – that's not far behind the US, which sits (never runs) at 71pc.