The low glycemic index diet has been used for weight loss, although its value -- for overall health and for weight loss specifically -- is still open to debate.
Originally developed to help people with diabetes better control blood sugar, the glycemic index has also been used to guide weight-loss efforts. The glycemic index ranks foods, particularly carbohydrates, by how quickly they raise blood sugar levels.
Diets based on the glycemic index typically promote eating "good" carbohydrates -- generally whole grains, fruits, nonstarchy vegetables, and beans -- rather than "bad" (refined) carbohydrates because the body digests them more slowly.
As a result, they do not affect blood sugar levels as much. This, in turn, may help you feel full longer, aiding in weight loss. However, the way the body responds to a particular food is affected by a number of factors, including how the food is processed and prepared and the other types of foods eaten along with it. The glycemic index is not a perfect system, and its value in weight loss is uncertain because of limited and conflicting research.
Some studies have linked a higher glycemic index to risk of coronary heart disease or type 2 diabetes. In addition, glycemic load, which takes into account not only the glycemic index but also the actual amount of carbohydrate per serving, has also been linked to risk of coronary heart disease.
In the Nurses' Health Study, women who consumed a diet with a high glycemic load had twice the risk of heart disease as those who consumed a diet with a low glycemic load; this was especially evident in women who were overweight or obese. However, further research is needed to determine whether these types of diets have an effect on the risk of heart disease.
Fasting is an extreme attempt at weight loss and is quite dangerous. Find out more about fasting, including why it's actually counter-productive, on the next page.