What Does Fiber Do to Blood Sugar?

Fruits and vegetables are packed with fiber.

Fruits and vegetables are packed with fiber.

Fiber can help prevent Type 2 diabetes and normalize blood sugar levels in diabetics. Fruits, vegetables and whole grains are packed with fiber. When you eat a meal that is rich in these nutrients, digestion occurs more slowly, which results in a longer absorption process in your body. Blood sugar or blood glucose levels are less likely to spike when eating these foods.

Blood Glucose and Diabetes

Fiber is a complex carbohydrate, which is found in fruits, vegetables and whole grains. According to the Academy of Nutrition and Dietetics, a fiber intake of 30 to 50 grams a day can result in lower blood glucose levels in individuals with diabetes mellitus. Type 2 diabetics have a pancreas that may not be releasing enough insulin, or they may suffer from insulin resistance, which causes abnormal blood glucose levels. When fiber is added to their diet, this carbohydrate can slow the increase in glucose levels, which reduces the amount of insulin their body is releasing.

Blood Glucose and Non-Diabetics

When a person without diabetes consumes food containing carbohydrate, the pancreas responds by releasing insulin to normalize blood glucose levels. When the average healthy person consumes fiber, blood glucose increases at a normal rate, insulin is released rapidly and blood glucose is reduced. The pancreas functions normally in healthy individuals; therefore, when fiber is consumed, it does not provide any additional benefits for blood glucose.

Glycemic Index

You can also refer to the glycemic index, which is a measurement of how rapidly the amount of carbohydrate found in food will cause blood glucose to increase. Foods with a higher glycemic index cause a greater increase in blood glucose than foods with a lower glycemic index. Foods high in fiber tend to have a lower glycemic index, but this may be affected by storage or ripening time of fruits and vegetables, overprocessing and cooking methods. The glycemic index does not take into account portion size or the combination of foods to make a meal.

Health Benefits

Eating fruits, vegetables and whole grains such as oat bran and barley can lower your blood pressure and cholesterol levels. It can also promote the growth of healthy bacteria within your colon, help you feel more satisfied after eating and prevent constipation. Fiber has also been correlated with lower body weights and may help prevent certain cancers such as colorectal cancer. The recommended amount that women should consume each day is 25 grams, and men should get 38 grams.

 

About the Author

Jennifer Tomesko has been a registered dietitian since 1997 and a certified nutrition support clinician since 1999. She earned a doctorate in clinical nutrition from the University of Medicine and Dentistry of New Jersey, where she also serves as an adjunct professor.

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