CARBOHYDRATES, HEALTH AND FAT LOSS

There is considerable scientific backing for the health benefits of a diet with a high proportion of starches. National health targets suggest that carbohydrates should provide about 55-60 per cent of daily energy. Unfortunately, carbohydrate intake in most Western countries has declined this century with the increased consumption of fat. Fibre intake in most Western countries averages only about half the national target of an achievable 30g per day.

The first idea that fibre could protect against certain diseases appeared in I960, when researchers observed that the degenerative illnesses common in affluent societies were rare in rural Africa where diets were high in unrefined plant foods. Subsequent studies confirmed the health properties of fibre and it is now considered to have a role in protection against chronic diseases such as cardiovascular disease, colorectal cancer, and the management of constipation and diabetes. The specific benefits depend on the type of fibre. Foods high in insoluble fibre reduce transit time (i.e. shorten the time for food to pass through the GIT), soften stools by holding water and increase stool volume. In contrast, foods high in soluble fibre have little effect on bowel transit but appear to slow the rate of carbohydrate absorption due to their gel-forming ability. This helps to reduce rapid fluctuations in blood glucose and insulin among people with diabetes.

The combination of the effects of different fibres (including resistant starch), the SCFAs produced and a diet low in fat are all thought to protect health, so it has been difficult to credit any one factor. Nutritionists therefore recommend a diet low in fat with a variety of foods containing all types of starch and fibre.

A low intake of carbohydrate in any form appears to be linked to obesity on a population level because, by default, it is a high-fat diet. The claim that carbohydrates, whether as sugars or starches, are fattening’ is a myth. However, it is prudent for some individuals who are obese and who consume large quantities of sugars, to moderate their intake as a second level of priority after decreasing fat.

*105\186\4*