Despite this, a number of food-combining diets abound, based on the principles of Dr Hay, a physician writing back in the 1930s. He emphasised eating wholefoods and lots of fruit and vegetables; he also advocated eating fruit away from other foods, since, if trapped in the stomach after a steak for example, fruit can ferment. So far, so good. He also recommended never eating carbohydrate-rich foods with protein-rich foods. So, for example, fish with rice or chicken with potatoes is out. The only study I’ve seen recommending that overweight or obese people follow this kind of diet showed a 3.5 per cent average body-weight change over 12 weeks. Although subjects in this trial were not advised to eat less or change the kind of food they ate, there was no measure to indicate whether this weight loss was solely due to food-combining or changes in the quantity or quality of food. It is now known, however, that combining protein with carbohydrate slows down the release of sugars from a meal to the blood stream, helps stabilise blood sugar levels and hence helps control weight. Since the majority of overweight people have blood sugar problems, it would seem that combining protein with carbohydrate would be better, not worse for you. So, in my book, fish with rice is in, not out. This is the staple diet, along with fruits and vegetables, of many island and coastal people around the world, many of whom are exceedingly healthy and slim. Dr Hay’s approach, if followed strictly, is probably best for those with digestive problems and worst for those with blood sugar problems. I remain to be convinced that the benefits reported by those on food-combining diets aren’t largely due to changes in the kind of foods eaten, rather than their noncombination.