When you eat foods such as a piece of bread or an apple, your body breaks down the carbohydrates that they contain to make glucose, which enters your bloodstream. The glycemic index of carb-containing foods indicates how quickly they raise your blood glucose level. The foods are rated on a scale of 0 to 100. The most nutritious foods have a GI of 55 or less because they pass through your digestive system slowly and don't spike your blood glucose levels.
Legumes are beans, peas, lentils and soybeans. This food group has many low GI choices that you should include in your daily diet. Kidney beans and lentils each have a GI of only 29, according to Harvard Health Publications, which makes them very nutritious. A 100-gram serving of cooked kidney beans provides 23 grams of carbohydrates that digest slowly, 9 grams of protein and 405 milligrams of potassium. The same-size serving of lentils has 20 grams of carbohydrates, 9 grams of protein and 8 grams of fiber.
When you choose carbohydrate-containing foods made from grains like wheat, rice or oats, the most healthful choices are foods made from whole grains as opposed to those made from refined grains. Brown rice, for example, is made from whole-grain rice and has a glycemic index of 50. Brown rice has more vitamins, minerals and fiber than white rice, which is a refined grain product. Bulgur or cracked wheat is a whole-wheat product and has a glycemic index of 48.
Make dairy products a part of your diet because they are good sources of protein, potassium, calcium and vitamin D. The carbohydrates in dairy products have low GIs. Whole milk has a glycemic index of 41, skim milk comes in at 32 and reduced-fat yogurt with fruit has a GI of 33. One of the health benefits of including dairy products in your diet is a lower risk of Type 2 diabetes.
Fruits and Vegetables
It is difficult for your digestive system to break down the complex carbohydrates in fruits and vegetables, so glucose forms slowly from these carbohydrates. This is why so many raw fruits and vegetables have a low glycemic index. The GI of apples, for example, is 39; oranges are 40 on the GI scale and pears have a glycemic index of 38. As for vegetables, raw carrots have a glycemic index of 35, and yams are rated at 54.
- American Diabetes Association: Glycemic Index and Diabetes
- Harvard Health Publications: Glycemic Index and Glycemic Load for 100+ Foods
- MyFitnessPal.com: Beans, Kidney, Cooked
- MyFitnessPal.com: From USDA-Lentils, Mature Seeds, Cooked
- Harvard School of Public Health: Replacing White Rice With Brown Rice or Other Whole Grains May Reduce Diabetes Risk
- ChooseMyPlate.gov: Dairy
- Centers for Disease Control and Prevention: Carbohydrates
Robert DiPardo has been a pharmaceutical chemist for more than 30 years. He has co-authored several scientific publications on cardiovascular disease, osteoarthritis, Alzheimer's disease and other therapeutic areas. DiPardo retired from drug discovery research in 2009 and, since 2010, has covered fitness and well-being for various online publications. DiPardo holds a Master of Science in organic chemistry from Yale University.