The glycemic index measures the ability of a food to raise blood sugar. Glucose is assigned a value of 100, meaning that it raises blood sugar significantly, and other foods are compared to it. According to Dr. Gabriel Mirkin, who is board-certified in four specialties, including sports medicine and immunology, sugar and refined grains are high-glycemic foods, while meats, fats, whole grains and vegetables are low-glycemic foods.
Modern Diet
The diet commonly eaten in Western, industrial countries is unquestionably rich in high-glycemic foods. According to Dr. Jacob Teitelbaum, a chronic fatigue specialist and author of "From Fatigues to Fantastic," added sugar supplies 18 percent of the calories consumed by an average American. White flour, another high-glycemic food, contributes another 18 percent of calories. The potato, has a glycemic score of 75 when it is served as French fries. In contrast, most vegetables have glycemic scores of approximately 15.
Agriculture
Before mankind began practicing agriculture, humans ate what is sometimes known as the Paleolithic diet. According to a 2009 article published in "Cardiovascular Diabetology," observations of existing hunter-gatherer peoples show that this diet is rich in meats, fish, nuts, vegetables and fruits, which are low-glycemic foods. After people adopted agriculture, they began eating more high-glycemic foods like grains, starchy vegetables, such as potatoes, and sugar. While most non-starchy vegetables have scores of 15 on the glycemic index, even relatively healthy whole grains have scores of at least 48.
Refined Grains
Refined grains have even higher glycemic values than whole grains. For example, wheat kernels have a low value of 41 on the glycemic index, while multigrain bread has a score of 48 and whole wheat bread has a score of 50. In contrast, white bread and baguettes have values of 71 and 95, respectively. Non-instant oatmeal, which was once a common breakfast food, scores 49, while cornflakes, which are made from refined corn, have a value of 93.
Food Subsidies
There is some evidence that government subsidies may play a role in promoting a high-glycemic diet. The PBS documentary show "POV" explored this topic in "Food, Inc." Robert Kenner, the director of "Fast Food Nation" stated that chips, sodas and fast food hamburgers are cheaper than broccoli because these foods are subsidized by the government. The best predictor of obesity is poverty, he claims, because poor people can only afford subsidized -- and high-glycemic -- foods like corn syrup and wheat flour and are unable to afford vegetables and fruits.
References
- Mayo Clinic; Diabetes; Maria Collazo-Clavell
- Dr. Mirkin.com; Glycemic Index and Glycemic Load; Gabe Mirkin
- South Beach Diet Plan for Beginners: Glycemic Index Food Chart
- PBS: POV: "The Dollar Menu"
- "Cardiovascular Diabetology"; Beneficial Effects of a Paleolithic Diet On Cardiovascular Risk Factors in Type 2 Diabetes: A Randomized Cross-over Pilot Study; T. Jonsson, et al.; July 2009
- "From Fatigued To Fantastic"; Jacob Teitelbaum; 1996
