Q. How do I get enough fiber in a gluten-free diet?
A. Having enough fiber in the diet is very important for people with celiac disease. Dietary fiber is the part of whole grains, fruits, vegetables, nuts, seeds and legumes (dried beans, peas and lentils) that cannot be broken down by the digestive tract.
Fiber helps maintain regular bowel movements, often a cause of trouble for people with celiac. Some with celiac disease suffer with diarrhea before their diagnosis, but the intestinal damage heals after they are on a gluten-free diet. The diarrhea stops, but at times, constipation develops.
Others with celiac may have experienced constipation prior to diagnosis, and find it gets worse once they’re on a gluten-free diet. In both cases, the constipation is a result of eliminating the foods they used to eat that are high-fiber: wheat bran, whole wheat breads and cereals.
Unfortunately, many gluten-free foods are made with starches and refined flours that are low in fiber, such as white rice flour, tapioca starch, corn starch and potato starch. The good news is there are many excellent gluten-free alternatives to whole wheat and wheat bran that are high-fiber.
Gluten-Free Grains, Flour & Starches
112 g in 1 cup, 14.7 g of dietary fiber
195 g in 1 cup, 18.1 g of dietary fiber
135 g in 1 cup, 12.6 g of dietary fiber
Buckwheat Flour (whole groat – ensure it’s 100% buckwheat flour and not mixed with wheat flour)
120 g in 1 cup, 12 g of dietary fiber
168 g in 1 cup, 45.9 g of dietary fiber
Flax Seed Meal (Ground Flax)
130 g in 1 cup, 35.5 g of dietary fiber
120 g in 1 cup, 20.9 g of dietary fiber
157 g in 1 cup, 12 g of dietary fiber
146 g in 1 cup, 46.1 g of dietary fiber
150 g in 1 cup, 36 g of dietary fiber
170 g in 1 cup, 10 g of dietary fiber
112 g in 1 cup, 6.6 g of dietary fiber
Rolled Oats (pure, uncontaminated)*
105 g in 1 cup, 9 g of dietary fiber
Oat Bran (pure, uncontaminated)*
150 g in 1 cup, 18.7 g of dietary fiber
Oat Flour (pure, uncontaminated)*
120 g in 1 cup, 12 g of dietary fiber
134 g in 1 cup, 39 g of dietary fiber
180 g in 1 cup, 11.2 g of dietary fiber
130 g in 1 cup, 8.7 g of dietary fiber
58 g in 1 cup, 24.8 g of dietary fiber
Whole Wheat Flour
120 g in 1 cup, 14.6 g of dietary fiber
125 g in 1 cup, 3.4 g of dietary fiber
* Commercial oat products are contaminated with wheat, rye and/or barley. The only oat products allowed on a gluten-free diet are pure, uncontaminated oats, which are usually labeled with a gluten-free claim. All values, except oats, are from Gluten-Free Diet: A Comprehensive Resource Guide– Expanded Edition, 2006. by Shelley Case, RD.
Increasing Your Fiber Intake
• Do it gradually. Start with a small amount and slowly increase it, to prevent major abdominal pain and gas.
• Increase consumption of fluids, especially water.
• When choosing gluten-free flour mixes or recipes, opt for ones with high-fiber flours and starches, like those shown.
• Add oat bran, rice bran, ground flax or mesquite flour to baked products, pancake batter or hot cereals.
• Use brown rice, wild rice, buckwheat, quinoa or teff in salads or pilafs instead of white rice.
• Add chickpeas (garbanzo beans), kidney beans or other bean varieties to casseroles and salads.
• Make high-fiber soups with lentils, split peas and/or beans.
• Choose high-fiber snacks such as nuts, seeds, dried fruits, popcorn, gluten-free snack bars (with dried fruits, nuts and seeds), raw vegetables and fruits.
• Add dried fruits, nuts or seeds to hot cereal, salads, stir-fry dishes, muffins, cookies and breads.
• Eat whole fruits and vegetables rather than drinking juice.
Shelley Case, RD, is an international celiac nutrition expert, consulting dietitian and author of Gluten-Free: The Definitive Resource Guide. Learn more at ShelleyCase.com. Shelley Case is on the advisory boards of the Canadian Celiac Association, the Celiac Disease Foundation and the Gluten-Free Intolerance Group.