Getting enough fiber in your diet is difficult, especially when you are on a low-carbohydrate diet. But if you eat enough of the right foods that are high in fiber, it is possible.

My previous blog entry on “Fiber and Diabetes” raised many questions, both in the comments and email to me, about what to eat. That blog entry focused on the general sources of fiber. This one focuses on particular foods that are high in fiber.

Most of us think that we are getting enough fiber. We aren’t.

When researchers asked people if the amount of fiber they consume is “about right,” 73 percent of those who consumed less than 20 grams per day agreed. This comes from the “Third National Health and Nutrition Examination Survey” cited in the American Dietetic Association’s position statement on “The Health Implications of Dietary Fiber”.

The American Dietetic Association goes on to say that healthy adults need 20 to 35 grams of fiber per day. We don’t meet that need “because intakes of good sources of dietary fiber, fruits, vegetables, whole and high-fiber grain products and legumes are low.”

More specifically the Food and Nutrition Board recently set the adequate intake level of total fiber at 25 grams per day for young women and 38 grams per day for young men. Young means less than 51 years old.

Old women need only 21 grams per day and old men need only 30. That’s because old folks don’t eat as much, they say.

This Food and Nutrition Board is semi-official. It’s a unit of the Institute of Medicine, which in turn is a part of the National Academy of Sciences, a private, nonprofit corporation created by an Act of Congress. It acts as an adviser to the federal government on issues of medical care, research, and education.

To find the specific foods that will help us to make up this gap I turned to my “Fiber” file, where I have been saving this sort of resource for years. Two of the best sources are not free online. Plant Fiber in Foods by James W. Anderson is a 1990 booklet of the HCF Nutrition Research Foundation, P.O. Box 22124, Lexington, KY 40522. Only the abstract of “Content and composition of dietary fiber in 117 frequently consumed foods” by Judith A. Marlett in the February 1992 issue of the Journal of the American Dietetic Association is free online.

But we do have two excellent online resources about fiber in specific foods. Dr. Anderson’s “Dietary fiber content of selected foods” came out in an 1988 issue of the American Journal of Clinical Nutrition. Less technical but perhaps more useful for most of us is Northwestern University’s “Nutrition Fact Sheet: Dietary Fiber”.

Starting with the Northwestern fact sheet you can get 5 to 7 grams of fiber from a cooked half cup of most legumes or beans. Then, barley is the cereal grain with the most fiber, about 4 grams in a half cup. That’s fortunate, because barley has the lowest glycemic index of any grain.

Among fruits, a medium apple will give you about 6 grams more of fiber. An orange or a pear have almost as much. Three small figs – when you can get them – will give you 5 grams. A half cup of raspberries will give you 4 grams.