The glycemic index measures how carbohydrates affect your blood sugar level. Carbohydrates that break down quickly during digestion raise blood glucose levels and rate high on the glycemic index. Carbohydrates slow to break down score low on the glycemic index. Also helpful to know is a food’s glycemic load, which measures the amount of carbohydrates you intake. Food with a low glycemic index and glycemic load, considered healthier for you, includes most fruit and vegetables, legumes, nuts and whole grains, such as rye bread.
Whole-grain products maintain the integrity of the original wheat, while refined grains lose nutrients and fiber during processing. One slice of rye bread has a glycemic index of 41 and a glycemic load of 5, according to the Linus Pauling Institute at Oregon State University. In contrast, one slice of white bread, made from refined grains, has a GI of 73 and a GL of 10. A high glycemic index is considered 70 or more, and low is 54 or less; a high glycemic load is 20 or more, and low is 10 or less.
Blood Sugar Levels
The rapid increase of blood sugar level after eating high-glycemic index foods – such as white bread, potatoes, white rice, breakfast cereal, baked goods and sweets -- signals the pancreas to secrete more insulin. High levels of insulin can then sharply decrease blood sugar to dangerously low levels and eventually lead to various health problems. On the other hand, eating foods with a low glycemic index sustains a more even distribution of blood glucose and allows the pancreas to function more efficiently.
Other benefits of eating rye and other food with a low glycemic index include a decreased risk of diabetes, cardiovascular disease, diverticulitis, constipation, gallstones and cancer, decreased inflammation, insulin-resistance and LDL -- or “bad” -- cholesterol, and help with weight loss.
A low-glycemic index diet emphasizing rye bread, beans, lentil and nuts results in better glycemic control and lower risk for coronary heart disease when compared with a diet high in “brown” cereal fiber – whole-grain breads and cereals, brown rice and potato skins, according to a study published in the Dec. 17, 2008, issue of the “Journal of the American Medical Association.” Both diets included three daily servings of fruit and five daily servings of vegetables. The study concluded that “low-glycemic index diets may be useful as part of the strategy to improve glycemic control in patients with type 2 diabetes taking anti-hyperglycemic medications.”
- Linus Pauling Institute at Oregon State University; Glycemic Index and Glycemic Load; Jane Higdon, Ph.D.; 2005
- University of Michigan Health System; Healing Foods Pyramid; Monica Myklebust, M.D. and Jenna Wunder, M.P.H., R.D.; 2011
- Medical News Today; In Patients with Diabetes, Low-Glycemic Diet Shows Greater Improvement in Glycemic Control than High-Fiber Diet; Dec. 17, 2008