The glycemic index measures the effects of certain carbohydrates. Carbohydrates that raise blood glucose levels only small amounts are categorized as low-glycemic foods, and a diet that contains a significant amount of low-glycemic foods offers health benefits, such as reducing the risk of heart disease and diabetes, according to the Glycemic Index.com.
Types of Low-Glycemic Carbs
Low-glycemic carbohydrates consist of fresh and canned fruits, vegetables, whole grains and legumes. Low glycemic foods have a GI index of 55 or less. Intermediate-glycemic foods have a GI index of 56 to 69.
Carbohydrates that fall in the low-glycemic category include broccoli, cauliflower, eggplant, green beans, peanuts, low-fat yogurt, lettuce, spinach, tomatoes, peas, grapefruit, canned peaches, soy milk, pearled barley, dried apricots, cooked carrots and spaghetti.
Carbohydrates that fall in the intermediate-glycemic category include white rice, popcorn, canned apricots, Grape-Nuts, instant oatmeal, Bran Chex, pineapple, American rye bread, taco shells, hamburger buns, canned fruit cocktail and linguine.
Because the consumption of low-glycemic carbohydrates does not cause blood sugar levels to spike, there is little to no risk of experiencing a "crash" after eating a meal. Low-glycemic carbs are easily assimilated by the body and do not cause a rapid energy boost. These foods provide a steady stream of energy instead, making them a beneficial choice for people who need to maintain steady blood sugar levels or for athletes who need to eat foods that boost performance.
Some of the proven health benefits of eating a diet rich in low-glycemic carbohydrates include a reduced risk of heart disease, reduced blood cholesterol levels, prolonged physical endurance, easy weight loss and improved muscle recovery after an intense workout. A low-glycemic diet also helps manage symptoms of polycystic ovary syndrome (PCOS) and increases the body's sensitivity to insulin.
There are several factors that can alter the glycemic index of food. Eating a variety of different foods at the same time can tax the digestive system and trigger the overproduction of insulin. Eating foods that contain protein, fat or fiber with the carbohydrate can slow down the absorption of the food, thereby reducing the glycemic effects of the meal. Food that is mashed, pressed or ground will have a higher glycemic index. The glycemic index can be reduced significantly by cooking, steaming or burning the food.
Each person reacts differently to different types of food based on their body composition. A person who has high blood sugar levels will be more sensitive to high-glycemic foods than someone who has healthy blood sugar levels.
The majority of processed and packaged foods fall high on the glycemic index because they contain high levels of sugar, white flour or artificial sweeteners. Foods found in the perimeter of the grocery store (fresh, unprocessed foods) typically fall low on the glycemic index.
Eating a low-glycemic diet does not mean all high-glycemic carbohydrates need to be eliminated. However, it does mean that the majority of carbohydrates consumed need to be low-glycemic carbs and that high-glycemic carbs must be mixed with protein, fiber or fat when they are consumed so that they are assimilated more slowly.
Blood sugar does not always rise at the same rate as insulin levels when consuming low-glycemic carbohydrates. This is significant, because people who need to manage their insulin levels must refrain from eating too many low-glycemic carbohydrates in one meal. Insulin levels will continue to increase when any type of carbohydrate is consumed, so even if blood sugar levels are not affected, insulin levels can become too high.