Do Fiber Supplements Lower Cholesterol Levels?

The answer depends on the type

Fiber is an important part of any healthy diet. Although fiber is mostly known for improving digestive health, studies have also shown that certain types of fiber can also help lower your cholesterol levels. This can include common brand-name fiber supplements like Metamucil and Citrucel.

This article discusses the different types of fiber and fiber supplements that can help lower your cholesterol levels—and which ones can't.

fiber supplement capsules
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Types of Fiber Supplements

There are two types of fiber that are incorporated into various fiber supplements: soluble and non-soluble fiber. Soluble fiber can be further divided into two types: nonviscous and viscous.

Viscous soluble fiber becomes a thick gel when it comes in contact with liquids in the digestive tract. Due to this characteristic, this type of fiber can bind to cholesterol in the small intestine. This prevents its absorption into the bloodstream and allows it to be eliminated in the feces.

Insoluble fiber and nonviscous soluble fiber do not possess the ability to bind to cholesterol in the small intestine.

You will want to read the label of any fiber supplement to see which type of fiber it includes. Fiber supplements are available over the counter in your local pharmacy, grocery store, or health foods store in the form of a tablet or powder.

LDL vs. HDL Cholesterol

When it comes to lowering cholesterol, LDL (rather than HDL) is the target.

Fiber Supplements That May Lower LDL

When you are looking for a fiber supplement for the purpose of lowering your cholesterol, start with psyllium or methylcellulose. Both have that have research supporting their use to slightly reduce LDL.


Psyllium is a type of viscous soluble fiber. It comes from the husks of seeds from the psyllium plant (Plantago ovata).

It is found in a variety of whole-grain foods as well as fiber supplements such as Konsyl, Metamucil, and other store-brand versions.

Psyllium has been the most extensively studied soluble fiber, either administered alone as a supplement or included in a variety of grains. Studies have shown that doses anywhere between 6 and 15 grams per day are able to lower LDL levels between 6% and 24%.


Methylcellulose is a modified form of cellulose. It is found in fiber supplements such as Citrucel and various store brands. This viscous soluble fiber does not have as many studies as psyllium that support its use for lowering cholesterol.

Fiber Supplements That May Not Lower LDL

There are other soluble fiber supplements that do not have studies in place to support their use in lowering cholesterol levels. These can still be used for digestive health, however.

  • Polycarbophil (FiberCon, FiberLax, Store Brands): Polycarbophil is a form of soluble fiber. Studies have not been able to show that it can lower LDL cholesterol in comparison to psyllium and methylcellulose.
  • Wheat Dextrin (Benefiber, Store Brands): Wheat dextrin is a nonviscous form of soluble fiber. It is not able to form a gel-like material within the small intestine and therefore cannot bind cholesterol.

Using Fiber Supplements

The USDA recommends adults up to age 50 consume 25 grams of fiber daily for women, and 38 grams a day for men. If you are unable to get enough fiber into your diet, taking a supplement may seem like a good solution. However, you should not rely exclusively on supplements for fiber.

There are plenty of delicious, fiber-rich foods that you can incorporate into your diet. These not only supply you with the fiber you need, but they can also introduce additional vitamins and other nutrients to your meals.

You should always consult with your physician before adding fiber supplements to your cholesterol-lowering regimen.

When using fiber supplements for cholesterol, follow the directions on the packaging. Fiber supplements should be taken with a whole glass of water in order to prevent choking. The doses should be divided throughout the day in order to reduce some of the gastrointestinal side effects associated with taking fiber. These can include abdominal cramping and bloating.

Unless otherwise stated by your physician or pharmacist, you should not take fiber supplements around the same time as you take certain vitamins and other medications. Fiber may lower its effectiveness.

Frequently Asked Questions

  • Which fiber is best for lowering cholesterol?

    Viscous soluble fiber binds to cholesterol in the small intestine, helping to lower cholesterol levels. Fiber supplements for cholesterol should contain psyllium or methylcellulose—types of viscous soluble fiber.

  • How long does it take for fiber to lower cholesterol?

    Research suggests it takes about four weeks of consuming a fiber-rich diet to see a reduction in cholesterol levels.

  • How can I lower my LDL cholesterol naturally?

    Natural approaches to lowering LDL levels include reducing your intake of saturated and trans fats and adding foods rich in omega-3 fatty acids and soluble fiber. Whey protein has also been shown to be effective in lowering cholesterol. Also aim to exercise for 30 minutes a day most days of the week, quit smoking, lose weight (if needed), and limit alcohol intake.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  4. Cleveland Clinic. Supplements to help manage total cholesterol, LDL and HDL.

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  8. Mayo Clinic. Top 5 lifestyle changes to improve your cholesterol.

By Jennifer Moll, PharmD
Jennifer Moll, MS, PharmD, is a pharmacist actively involved in educating patients about the importance of heart disease prevention.