Fiber and Carbs in Your Diet

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Fiber and Carbs in Your Diet

Question:

My doctor told me I am dangerously close to being diagnosed with diabetes. She told me to "watch your carbs." My gastroenterologist just treated me for diverticulitis. He told me to add more fiber to my diet. How can I watch my carbs to avoid diabetes and get the fiber I need?

Answer:

I suspect your doctor wanted you to "watch your carbs" as part of an overall effort to keep down total calories and avoid weight gain. There is also a growing concern that very quickly digested carbohydrates may contribute to your risk for diabetes.

Quickly digested (or simple) "carbs" such as starches, milk sugars and sweeteners, can put a large load of glucose (sugar) into the bloodstream right after you eat. This means they have a high "glycemic index." For people who already have a tendency towards diabetes, large loads of glucose can be hard to process.

Researchers are currently debating whether all simple carbs are equally problematic, or if sweeteners are a special concern. The attention to sweeteners comes from the fact that most sweeteners contain fructose. Recent evidence has suggested that if there is a large amount of fructose in your diet, this might alter your metabolism in a way that increases your risk for diabetes.

Your best sources of fiber will be vegetables, fruits and whole grain foods. Although whole grain foods like whole-wheat bread and brown rice are mostly made up of carbohydrates, they don't create a blood sugar "spike" because you absorb these carbs very gradually. You should limit carbs found in highly processed foods such as sodas, juices, snacks, dessert foods and many sauces and dressings.

Mary Pickett, M.D., is a lecturer for Harvard Medical School and an assistant professor of medicine at Oregon Health & Science University in Portland, OR. At OHSU, she practices general internal medicine and teaches medical residents and students.

Last updated:	July 20, 2009