Fiber is important for healthy digestion, and diets that are high in fiber are linked to improved heart health. Food sources high in fiber include split peas, lentils, black beans, lima beans, artichokes, and raspberries. 

The U.S. Department of Agriculture recommends adults consume between 25 grams (women) and 30 grams (men) a day from food, but the average intake by adults in the United States is only about half of that.

Fiber supplements are available in many forms and allow people to increase the amount of fiber in their diets if they aren’t eating or getting enough from food. Short-term relief from constipation and bowel irregularity are common reasons people use fiber supplements. Dietary fiber supplements are also used in weight management because it helps people feel fuller longer, which is important in weight management. 

According to Mayo Clinic, while there is no evidence that fiber supplements are harmful, it’s better to get fiber from natural sources because you also get the vitamins and minerals that the foods provide. Whether you increase your fiber intake using a supplement or by eating a higher fiber diet, be sure to increase your fluid intake as you increase your fiber. Fluid is required to help push fiber through the digestive tract, and too little water with more fiber could worsen constipation.

Soluble vs. Insoluble Fiber:
  • Soluble fiber captures moisture and slows digestion. You can find it in oatmeal, nuts, apples, and carrots.
  • Insoluble fiber adds bulk to stool and can help ease constipation. You can find it in whole grains, fruit skins, and wheat bran.

The Types of Fiber

There are two kinds of fiber: soluble and insoluble.

Soluble fiber absorbs the water in your food, which slows down digestion. Slowing digestion can help regulate blood sugar. It’s also been shown to help reduce “bad” LDL cholesterol. You can find it in oatmeal, flax seed, barley, dried peas, oranges, applies, and carrots.

Insoluble fiber adds bulk to the stool, which helps move it through your digestive system quickly, and relieves constipation. It’s been shown to help balance the pH in your intestines and prevent colon cancer. You can find it in seeds, nuts, dark green leafy vegetables, and wheat bran.

Inulin (Fiber Choice)

Inulin is one of the types of prebiotic fiber, which means that it causes significant, favorable changes to your colon’s bacterial population. This is important, as these digestive bacteria play a major role in how well you absorb nutrients and even produce hormones related to anxiety and appetite.

Inulin can be found in chewable capsule form as Fiber Choice, which is 100 percent soluble fiber.

Takeaway: Inulin helps maintain gut bacteria.
Fiber Content of Fiber Choice Capsules: 3 grams per 2 capsules.

Methylcellulose (Citrucel)

Another common soluble fiber is methylcellulose, which is made from cellulose, an important structure in plants. It differs from psyllium because it is non-fermentable, meaning that it’s less likely to contribute to bloating and gas.

Methylcellulose is most commonly found on the shelves in products like Citrucel with SmartFiber, which is 100 percent soluble fiber and found in powder form. It’s also sold as a thickener and emulsifier in the culinary world. Because of methylcellulose’s chemical structure, it only dissolves in cold liquid and not hot (so don’t try to sneak some into your hot tea).

Takeaway: Less likely than psyllium to cause bloating and gas.

Fiber Content of Citrucel with SmartFiber Powders: 2 grams per scoop.
Fiber Content of Citrucel with SmartFiber Capsules: 1 gram per 2 capsules.

Psyllium (Metamucil)

Psyllium, which is also called ispaghula, is made from the seed husks of the plantago ovata plant. Psyllium contains 70 percent soluble fiber, which means it can help increase fullness and slow digestion. It also contains some insoluble fiber, so it passes through the gut relatively intact, providing bulk and helping to keep you regular.

Besides the overall good feeling of being regular, research has shown that psyllium — most commonly found as Metamucil — can ease the painful symptoms associated with irritable bowel syndrome (IBS), Crohn’s disease, hemorrhoids, and anal fissures.

Takeaway: Eases painful symptoms of IBS and Crohn’s disease.
Fiber Content of Metamucil Orange Smooth Powder: 6 grams per 2 tbsp.
Fiber Content of Metamucil Fiber Capsules: 2 grams per 5 capsules.

Wheat Dextrin (Benefiber)

Wheat dextrin, most commonly sold under the brand name Benefiber, is a manufacturing byproduct of the wheat plant. It’s tasteless and can dissolve in both hot and cold liquids. It can also be used in cooking and doesn’t thicken. Like most soluble fibers, it also helps regulate your digestion and stabilize blood sugar. 

Benefiber contains only soluble fiber, so it’s helpful to people trying to manage their blood sugar, such as people with type 2 diabetes. It also contains less than 20 ppm of gluten, so it meets the requirements to be labeled gluten-free. 

Takeaway: It’s gluten-free and can be added to food when cooking.
Fiber Content of Benefiber Powders: 3 grams per 2 tsp.

Before You Begin Taking Supplements

Increasing your dietary intake of fiber is generally considered safe for most people, but if you are experiencing gastrointestinal problems besides occasional constipation, you should discuss fiber supplements with your doctor first.