The glycemic index (GI) ranks carbohydrates according to their immediate effect on blood glucose levels. According to registered dietitian Joanne Larsen, the index is a measurement of how a 50-gram carbohydrate serving of a food affects one's blood glucose level compared with eating a 50-gram carbohydrate serving of glucose (which ranks 100) or white bread (which ranks 70).
Carbohydrates that rank high on the glycemic index break down rapidly during digestion, causing a quick spike in blood sugar. Low GI carbohydrates break down slowly, causing small, gradual variations in blood sugar, which helps reduce the risk of heart disease and diabetes, and is a significant factor for losing (and maintaining) weight.
Here is the Glycemic Index ranking:
- High (bad) GI Foods: 70 and above
- Medium GI Foods: 56 to 69
- Low (good) GI Foods: 55 and below
Why Does the Glycemic Index Matter?
It is true: we are what we eat. High GI foods not only increase blood glucose levels, but the quick energy also burns quickly, leaving us vulnerable to energy crashes. High GI foods also stimulate food cravings, which can lead to overindulgence and increased fat storage. It’s no surprise, then, that diets rich in high GI foods tend to increase BMI (body mass index). High BMI’s are linked to problems with obesity, heart disease, and diabetes.
Low GI foods, however, typically have much less impact on body mass, and those who eat a lot of low GI foods generally have lower levels of body fat. Low GI foods tend to keep blood sugar levels relatively constant, which helps to regulate energy, to lose or maintain weight, and to reduce the risk of heart disease. Low GI foods are, quite simply, healthier choices.
Switching to a Low Glycemic Diet
It isn’t necessary to sacrifice good-tasting foods to stay healthy. Start by eating more high-fiber foods—particularly foods high in soluble fiber—and fewer foods based on refined grains, starches, and/or sugar.
For example, choose unsweetened cereals based on oats, barley, or wheat bran. Opt for pasta, Basmati rice, or quinoa in place of potatoes. Choose yams or sweet potatoes instead of white potatoes. Eat whole-grain breads, especially those with seeds, instead of white bread. Fresh, unprocessed foods—such and apples, broccoli, and legumes—tend to be lower on the glycemic index, higher in fiber, and healthier choices in general.
Foods to eat in small, fairly infrequent amounts include white bread, white rice, potatoes, and carbonated beverages. All these foods tend to be higher GI foods.
Additional Benefits of Low Glycemic Foods
Low glycemic carbohydrates help prolong physical endurance, so a diet comprised mostly of low GI foods is excellent for athletes or anyone who is physically active.
