Everything you eat is digested by your body and absorbed into the bloodstream. The glycemic index is a way of determining how each food, after being absorbed, will impact your blood glucose. Eating according to the glycemic index may be a favorable way of dieting for some. For those trying to lose weight, the glycemic index offers a way of choosing foods without counting calories. For diabetics, the glycemic index may offer better glucose management.
The Glycemic Index
The glycemic index is a means of determining the effect a certain food has on your blood glucose. The glycemic index ranks foods as low, moderate or high glycemic foods based on the impact they have on your blood sugar. The glycemic effect can range from a large spike followed by a severe plummet of blood glucose to a slow and moderate rise over a prolonged period of time. A low glycemic food produces a moderate rise over an extended time frame while a high glycemic food results in a large rise and fall in blood glucose.
Glycemic Index Rankings
There are three categories that foods fit into according to the glycemic index: low, moderate and high. The glycemic index scores foods on a scale from zero to 100. Foods that are ranked between zero to 55 are considered low glycemic foods that slowly release glucose into your blood stream. From 56 to 69, is a moderate glycemic food, resulting in a moderate release of glucose over a shorter period of time. Foods greater than 70 are high glycemic foods that can spike your blood glucose shortly after eating. Low glycemic foods include non-starchy vegetables and legumes. Moderate glycemic foods are bananas, pineapples and corn. Examples of high glycemic foods include white rice, white bread and starchy vegetables.
Glycemic Index and Weight Loss
The glycemic index is useful for the overweight or obese trying to lose weight. Eating foods lower on the glycemic index can provide increased satiety than foods higher on the index. A smaller rise in blood glucose means a smaller amount of insulin is released into your bloodstream. According to the book "Nutrition" by Sizer and Whitney, these foods have been linked to increasing satiety. If you are satisfied after a meal and this satisfaction can last until your next meal, you are less likely to overeat, resulting in more favorable weight loss.
The Glycemic Index for Diabetes
Part of managing your diabetes effectively is gaining control over your blood glucose. In order to avoid suffering from diabetes-related complications, you should always try to keep your blood sugar levels in a normal range. The glycemic index diet can help offer the diabetic increased glycemic control. Since the glycemic index rates foods based on their effect on your blood glucose, it can be a helpful tool for diabetics. Eating low to moderate glycemic index foods can give you a good idea of how your meal will impact your blood glucose. According to the American Diabetes Association, combining carbohydrate counting with the glycemic index can increase blood glucose control.
Considerations
While the glycemic index can be a useful tool for weight loss and glycemic control, it does not take all the aspect of food intake into account. For instance, the glycemic index does not consider the amount of the food you are eating or how it is prepared. If you are dieting or if you have diabetes, you should be aware of the portion sizes you are eating, as well as the potential impact this will play on your blood glucose. A larger portion of food will contain more calories as well as lead to a larger increase in blood glucose.
References
- "Nutrition: Concepts and Controversies"; Frances Sizer and Eleanor Whitney; 2004.
- Mayo Clinic.com; Glycemic Index Diet: Losing Weight with Blood Sugar Control; November 24, 2009
- American Diabetes Association; Glycemic Index and Diabetes; 2010
