How does soluble fiber affect the glycemic index to help with diabetes?

Janis Jibrin, MS, RD
Nutrition & Dietetics
Soluble fiber, the type of fiber found in oats, barley, psyllium, beans, and certain fruits and vegetables, lowers the glycemic index (GI) of a food in a few different ways. When it mixes with liquid and with your own digestive juices, it forms a gel which slows the rate at which your stomach empties. Once in the small intestine, that gel forms a protective layer around starch particles, making it difficult for enzymes to penetrate. In studies in which people with diabetes took in 10 to 20 milligrams of soluble fiber daily for weeks, their average blood sugar was lowered slightly. After the soluble fiber makes its way to the large intestine, it becomes a meal for friendly bacteria, which convert dietary fiber into short-chain fatty acids that appear to help your blood sugar in two ways. Their presence sends a signal to the liver to stop making glucose and they also appear to increase insulin sensitivity.
The Best Life Guide to Managing Diabetes and Pre-Diabetes

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The Best Life Guide to Managing Diabetes and Pre-Diabetes

Bob Greene has helped millions of Americans become fit and healthy with his life-changing Best Life plan. Now, for the first time, Oprah's trusted expert on diet and fitness teams up with a leading...

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Diabetes mellitus (MEL-ih-tus), often referred to as diabetes, is characterized by high blood glucose (sugar) levels that result from the body’s inability to produce enough insulin and/or effectively utilize the insulin. Diabetes ...

is a serious, life-long condition and the sixth leading cause of death in the United States. Diabetes is a disorder of metabolism (the body's way of digesting food and converting it into energy). There are three forms of diabetes. Type 1 diabetes is an autoimmune disease that accounts for five- to 10-percent of all diagnosed cases of diabetes. Type 2 diabetes may account for 90- to 95-percent of all diagnosed cases. The third type of diabetes occurs in pregnancy and is referred to as gestational diabetes. Left untreated, gestational diabetes can cause health issues for pregnant women and their babies. People with diabetes can take preventive steps to control this disease and decrease the risk of further complications.

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