The alternate day diet seems to get round that because it allows normal eating as well.
'We've run trials that haven't found any reduction in metabolic rate when people are on the alternate day diet,' says Dr Johnson.
As all dieters will know, there is nothing more tedious than counting calories or weighing foods for a meal plan. But there's now an effective weight-loss regimen that is not only simple, it promises significant health benefits - from easing asthma symptoms and reducing blood sugar levels, to fending off heart disease and breast cancer and protecting brain cells. The diet goes under various names - The Alternate-Day Diet, Intermittent Fasting or The Longevity Diet - but the principle is the same: eat very little one day (50 per cent of your normal intake) and as much as you like the next.
This appears to trigger a 'skinny' gene that encourages the body to burn fat.
They ate 20 per cent of their normal intake one day and a regular, healthy diet the next.The animal had clearer arteries, lower levels of inflammation, better blood sugar control and its brain cells were less likely to get damaged.Meanwhile, rates of diseases linked to ageing all dropped.'We advise anyone trying to lose weight should follow a healthy balanced diet,' said a spokesperson for the Food Standards Agency.'It may not be possible to achieve this with very low calorie diets.' However, Catherine Collins, spokesperson for the British Dietetic Association, was more enthusiastic about the weightloss benefits.