How Fiber Keeps Your Brain and Heart in Shape

Just about everyone knows eating fiber is the key to keeping you, um…regular. That's just one benefit of the food voted “Most Likely to Make a Middle Schooler Snicker.”

It’s true. High fiber foods make you poop. They also make you feel full faster so you’re likely to eat less. When you eat less, you’re less likely to pack on extra pounds — pounds that can cause health problems later.

Being overweight can lead to a higher risk of heart disease, stroke, diabetes and other serious health issues.

Fiber Fends Off Trouble

How? Your body can’t break down fiber. As it moves through your system, it slows digestion. It keeps you regular by making your stools softer and easier to pass. There are two types of fiber — soluble and insoluble. Both should be part of a healthy diet.

Soluble Fiber

This type of fiber attracts water much the way oats absorb water to turn into oatmeal. Soluble fiber turns into a gel during digestion. High-fiber foods that include soluble fiber include oatmeal, nuts, apples, blueberries, seeds, lentils, peas and beans.

Foods with high levels of soluble fiber help lower cholesterol, a key risk factor for heart disease. Fiber attaches to cholesterol particles and sweeps them along as fiber moves out of the body.

Fiber also helps fight diabetes. When your body doesn’t absorb foods with soluble fiber, you skip blood sugar spikes that put you at risk for Type 2 diabetes.

Finally, high fiber foods help you stay regular because they absorb water as the foods pass through your system. That helps bulk up your stool. In fact, fiber supplements generally contain mostly soluble fiber.

Insoluble Fiber

This type of fiber is found in the seeds and the skin of fruits (so always eat those peels!) — along with vegetables and whole grains. It adds bulk to the stool and helps food pass more quickly through the stomach and intestines. If you’re irregular (constipated), eat more high-fiber foods to get things moving. Insoluble fiber can improve other bowel-related health problems, such as hemorrhoids and bowel control.

How Much Fiber Do You Need?

Most Americans don’t eat enough high-fiber foods, according to current guidelines by the U.S. Department of Agriculture and U.S. Department of Health and Human Services. Women need 25 grams of fiber per day, but usually consume only 13 grams. Men need 38 grams per day, but eat only about 17.

Try these simple tips to add more high fiber foods to your diet:

• Eat two cups of fruit and two-and-a-half cups of vegetables each day. Beans, sweet potatoes, cauliflower and berries are good sources of fiber.
• Eat the peels of your apples and potatoes.
• Eat whole, rather than refined grains. Choose whole wheat bread, brown rice and oatmeal.
• Check food labels. Look for foods with five grams of fiber or more per serving.

Remember, it’s not just how much fiber you eat that keeps you healthy, but what kinds of fiber you choose to eat. What are your favorites?

Sources: Dietary fiber: Essential for a healthy diet,  The Mayo Clinic, 2022; Soluble vs. insoluble fiber,  U.S. National Library of Medicine, 2022  

Originally published 11/5/2015; Revised 2019, 2022, 2023