Not getting enough fiber in one’s diet can lead to fiber deficiency. Fiber helps support gut and microbiome health. Individuals not getting enough fiber may experience irregular bowel movements, constipation, blood sugar fluctuations, not feeling full/satisfied after eating, or rising cholesterol levels. About 100 trillion microorganisms in the gut are integral to maintaining a healthy immune system. Fiber is the food these microorganisms eat that helps them to do their job. Without the proper amount, the immune system’s health may also be compromised.

Fiber and Gut Health

Fiber and gut health benefits include regulating the body’s sugars, helping to keep hunger and blood sugar in check, helping to maintain a healthy weight, its ability to prevent or relieve constipation, reduce the risk of diabetes, heart disease, and certain types of cancer.

• Dietary fiber, or roughage, is the part of plant foods the body can’t digest or absorb.
• It passes through the stomach, small intestine, and colon and out of the body.
• It is found mainly in fruits, vegetables, whole grains, and legumes.
• Soluble and insoluble forms are important to overall health.

Types

Soluble Fiber

• This type dissolves in water to form a gel-like substance.
• It can help lower blood cholesterol and glucose levels.
• It is found in oats, peas, beans, apples, citrus fruits, carrots, and barley.

Insoluble Fiber

• This type of fiber promotes the movement of material through the digestive system.
• It increases stool bulk, benefiting individuals who struggle with constipation or irregular stools.
• Whole-wheat flour, wheat bran, nuts, beans, and vegetables, such as cauliflower, green beans, and potatoes, are good sources.

Benefits

Healthy Bowel Movements

• Dietary fiber increases stool weight and thickness and makes it soft.
• Fiber helps to solidify the stool by absorbing water and adding bulk.
• A thicker stool is easier to pass, decreasing the potential for constipation and other problems.

Maintains Bowel Health

• A high-fiber diet can lower the risk of developing hemorrhoids and small pouches in the colon/diverticular disease.
• Studies have also found that a high-fiber diet can help lower the risk of colorectal cancer.
• Some fiber gets fermented in the colon.
• Researchers are looking at how this can help prevent diseases of the colon.

Lowers Cholesterol

• Soluble fiber found in beans, oats, flaxseed, and oat bran can help lower blood cholesterol levels by lowering low-density lipoprotein or unhealthy cholesterol levels.
• Studies also have shown that high-fiber foods can help reduce blood pressure and inflammation.

Regulates Blood Sugar Levels

• In individuals with diabetes, fiber, particularly soluble fiber, can slow the absorption of sugar and improve blood sugar levels.
• A healthy nutrition plan that includes insoluble fiber can help reduce the risk of developing type 2 diabetes.

Helps Achieve Healthy Weight

• High-fiber foods can be more filling than low-fiber foods, helping individuals eat less and stay satisfied.
• High-fiber foods can also take longer to eat and are less energy dense, meaning they have fewer calories.

Getting More Fiber

Ideas for adding more fiber to meals and snacks:

Fiber to Start The Day

• Choose a high-fiber breakfast cereal with five or more grams of fiber per serving.
• Choose cereals with whole grain, bran, or fiber in the name.
• Add a few tablespoons of unprocessed wheat bran to the cereal.

Add Whole Grains

• Try to make at least half of the grains eaten whole grains.
• Look for bread that lists whole wheat, whole-wheat flour, or another whole grain as the first ingredient, with at least 2 grams of dietary fiber per serving.
• Experiment with whole-wheat pasta, brown rice, wild rice, barley, and bulgur wheat.

Baked Foods

• Substitute whole-grain flour for half or all white flour when baking.
• Add crushed bran cereal, unprocessed wheat bran, or uncooked oatmeal to muffins, cakes, and cookies.

Legumes

• Beans, peas, and lentils are recommended sources.
• Add kidney beans to soups or salads.
• Make nachos with refried black beans, fresh vegetables, whole-wheat tortilla chips, and healthy salsa.

Fruit and Vegetables

• Fruits and vegetables are rich in fiber and vitamins and minerals.
• Try to eat a favorite fruit daily.

Healthy Snacks

• Fresh fruits, raw vegetables, low-fat popcorn, and whole-grain crackers are healthy choices.
• Try for a handful of nuts or dried fruits; however, be aware that nuts and dried fruits can be high in calories.

Moderation

High-fiber foods are beneficial for the body’s health.

• Adding too much fiber can promote intestinal gas, abdominal bloating, and cramping.
• Increase fiber gradually over a few weeks.
• This allows the natural bacteria in the digestive system to make adjustments.
• Maintain hydration, as fiber works best when it absorbs water.

Individuals not sure how to incorporate more fiber can consult a nutritionist and health coach to help begin the process.

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Gut Dysfunction

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References

Anderson, James W et al. “Health benefits of dietary fiber.” Nutrition Reviews vol. 67,4 (2009): 188-205. doi:10.1111/j.1753-4887.2009.00189.x

Cronin, Peter, et al. “Dietary Fiber Modulates the Gut Microbiota.” Nutrients vol. 13,5 1655. 13 May. 2021, doi:10.3390/nu13051655

Fuller, Stacey, et al. “New Horizons for the Study of Dietary Fiber and Health: A Review.” Plant foods for human nutrition (Dordrecht, Netherlands) vol. 71,1 (2016): 1-12. doi:10.1007/s11130-016-0529-6

Gill, Samantha K et al. “Dietary fiber in gastrointestinal health and disease.” Nature reviews. Gastroenterology & hepatology vol. 18,2 (2021): 101-116. doi:10.1038/s41575-020-00375-4