• High-carbohydrate (low-fat) diet. In a diet consisting of 70% carbohydrates and 30% protein with no fat, some protein will be used for body building and repair, and some will be converted into glucose. All the carbohydrates will be converted to glucose initially. This will result in a rapid and sustained elevation in blood glucose levels, stimulating insulin production. Insulin stimulates cells to uptake glucose, as well as increasing appetite, causing most people to eat again not long after eating a high-carbohydrate meal. Insulin stimulates the body to store fat.
Thus, a high-carbohydrate diet will provide excess of what is necessary for immediate energy usage. Some will be converted to glycogen and stored in the liver, but most is converted into fat for storage in the body tissues.
• High-fat (low-carbohydrate) diet. In a diet consisting of 30% protein, 70% fat with no carbohydrates, proteins will be used as before, but in the absence of carbohydrates the body must ‘burn’ the fat it consumes. This causes the body to ‘convert’ to a fat-burning engine instead of being primarily a glucose-burning engine. Fats, unlike carbohydrates, have a high satiety factor; fats make you feel full, and the satiety lasts for hours. Therefore, you tend to consume fewer calories on a high-fat diet than on a high-carbohydrate diet. Also, with a lower carbohydrate intake, the levels of insulin are low. Therefore, the fat you eat tends not to be stored. Thus a high-fat diet, in the absence of carbohydrates, typically results in weight loss.”
