The low GI, or glycemic index, diet involves planning your meals based on the way different foods effect blood sugar levels. The GI diet was originally developed as a tool to help diabetics control blood sugar, although it became a popular weight loss diet after the people following it lost a noteworthy amount of weight. Proponents of the low GI diet claim that eating certain types of carbohydrates and avoiding others can help keep your blood sugar levels low.
Physiology
Carbohydrates provide you with glucose, which is the main source of energy for your body. Some carbohydrates move through your digestive system at a rapid rate and raise your blood sugar levels quickly and notably. Other carbohydrates move through your digestive system slowly, giving your body time to adjust and causing only a slight rise in blood sugar. When your blood sugar rises, your pancreas sends out the hormone insulin to lower it. Once insulin carries the glucose from your blood to your tissues, blood sugar levels drop again.
Low GI Diet Basics
The theory behind the low GI diet is that you can control the increases and decreases in your blood sugar levels with the type of carbohydrates you eat. If you regularly eat carbohydrates that cause significant spikes and drastic drops in blood sugar, you may develop a condition called insulin resistance, which is characterized by in inability to properly utilize insulin. Insulin resistance is associated with obesity, high blood pressure, heart disease and the development of type 2 diabetes. On the other hand, consuming slow-moving carbohydrates can keep your blood sugar levels low and steady and prevent serious health problems.
GI Scale
On the GI diet, foods are ranked based on their effect on your blood sugar level in relation to pure glucose, which has a GI of 100. Foods ranked from 70 to 100 are high on the glycemic index and should be avoided on a low GI diet. Examples of high GI foods include rice, white bread, potatoes and watermelon. Foods ranked from 56 to 69 have a moderate effect on your blood sugar levels and should only be eaten occasionally. Examples of these medium glycemic foods include bananas, pineapple, raisins and corn. The majority of your diet should consist of low glycemic foods, which rank from 0 to 55. These foods have the least effect on your blood sugar levels. Examples include peanuts, apples, beans, lentils, low-fat milk and grapefruit.
Considerations
Although the low GI diet was originally developed for diabetes patients, the use of the glycemic index as a management tool for the condition is controversial. According to a 2003 report published in the American Diabetes Association's journal "Diabetes Care," a low GI diet has a small but clinically significant effect on glycemic control in patients who have diabetes. The journal further notes that the effects of the low GI diet mimic that of pharmaceutical drugs that control high blood sugar.
