Low carbohydrate diets are often designed for fast weight loss. This is rarely effective in the long term because it is achieved mainly by loss of water and lean mass. The water is rapidly regained when normal eating is resumed. As well as being ineffective, these diets produce ketones (see also ketogenic diets) which can be harmful. Therefore, such diets should only be taken under medical supervision. Low carbohydrate diets can also increase blood cholesterol levels, cause hypoglycaemia, and disrupt the balance of minerals. The diets rarely provide sufficient nutrients and are usually difficult to follow.
Some people reduce their carbohydrate intake in the mistaken belief that carbohydrates are as fattening as pure fats. However, less fatty tissue is made by eating 2000 Calories of carbohydrates than by eating 2000 Calories of pure fat. Fat overeaters tend to put on weight more easily and to be overweight for longer than carbohydrate overeaters. Stated simply, excess fats are more fattening than excess carbohydrates.
Far from reducing the proportion of carbohydrate in the diet, most people would benefit from increasing it so that it contributes at least 50 per cent of food energy. Carbohydrate is a better source of energy for exercise than fat. Many dietitians recommend a diet rich in complex carbohydrates as the foundation of a weight-reducing diet, a sports diet, and healthy eating for all.
Subjects: Medicine and Health.