Supplements can be a powerful tool for lowering cholesterol when used in conjunction with a healthy lifestyle. Many of the most studied and effective supplements for lowering high cholesterol are different forms of fiber. Fiber in various forms, including psyllium husk, flaxseed and glucomannan, has been clinically effective in lowering cholesterol.
Psyllium husk is a soluble fiber supplement that absorbs water and expands once in the intestines. Unlike insoluble fiber, soluble fiber such as psyllium husk dissolves in water. The University of Maryland Medical Center notes that soluble fiber in particular is effective in lowering "bad" or LDL cholesterol, which can reduce the risk of heart disease. A 2008 study published in “Phytomedicine” found that over a three-week period, psyllium husk was able to significantly reduce LDL cholesterol and total cholesterol levels.
Flaxseed, which is derived from the Linum usitatissimum plant, is a soluble fiber supplement. MedlinePlus rates flaxseed as “possibly effective” for reducing cholesterol levels in people with high cholesterol. However, MedlinePlus notes that you should avoid partially defatted flaxseed because it can raise triglyceride levels. A 2008 study published in the “Journal of Women's Health” found that women who consumed flaxseed regularly had a reduced risk of heart disease due to lower LDL and total cholesterol levels.
Glucomannan, a soluble fiber, has been used by the Chinese for over 2,000 years to treat a variety of conditions, such as burns, coughs and asthma. A 2002 study tested the fiber supplements glucomannan and chitosan on 21 overweight subjects for 28 days, at a dosage of 2.4 grams per day. At the end of the study, LDL and total cholesterol levels were significantly lower. Drugs.com notes that in most clinical studies on glucomannan, between 1 and 13 grams daily are used.
It's important to assess your tolerance when taking fiber supplements because they can cause side effects such as gas and bloating in some people. University of Maryland Medical Center also notes that it’s important to consume an 8-ounce glass of water when taking fiber to avoid constipation or choking. Fiber supplements can also interfere with the absorption of medications, which is why you should take medications at least an hour before or two to four hours after taking any fiber pills.