Glycemic index values are a measure of the effects of carbohydrates on blood sugar levels. A high glycemic index value is attributed to carbohydrates that break down quickly and produce a rapid release of glucose in the bloodstream during digestion. The opposite is true of low glycemic index values, which are given to carbs that break down and release glucose slowly into the bloodstream. Low value carbs are usually considered healthier than high value ones.
Low glycemic index (GI) carbs keep blood glucose and insulin levels more level, leading to fewer blood sugar spikes than high GI value foods. This is beneficial because its helps to maintain long-term health and lessens the future risk of diabetes or heart disease. An added benefit is that a diet comprised mostly of low glycemic index values contributes to weight loss. It is especially important for people who already have diabetes or who are pre-diabetic to follow a diet with low glycemic index values.
There is a glycemic food index to help determine the glycemic index values of foods. In general, foods with a GI value of 55 or less are considered low GI. These include fruits and vegetables, excepting potatoes and watermelon; milk and yogurt; and whole-grain breads and pastas. Whole wheat products, table sugar and sweet potatoes are examples of medium GI foods, with values between 56 and 69.
Anything with a GI above 70 is considered high and should be consumed in moderation. Included in this group are white bread and pasta, most breakfast cereals that aren't whole grain, and white rice. White potatoes and watermelon are also on this list.
Switching to a low glycemic index diet can be done gradually, but the health benefits are often significant. Breakfast cereals high in bran, barley, or oats are a better choice than those made of wheat flour. A dieter may want to cut white breads, pastas, and rice out of the diet in favor of whole-grain products. People can incorporate salads with vinegar based dressings into the diet, and eat plenty of fruits and vegetables.
Low value glycemic index foods can help keep diabetes in check and lower the chances of becoming diabetic. They also reduce the risk of heart disease and help improve cholesterol levels. Low GI foods help an eater to feel full for longer periods and are metabolized more efficiently, leading to weight loss. They also increase and prolong physical endurance.