Cholesterol is a fatty, wax-like substance that exists in every cell of the human body. It plays a crucial role in creating hormones and other essential substances. However, when cholesterol levels in the blood become too high, it can increase the chance of heart problems and strokes. High cholesterol usually doesn’t present any symptoms, so the only way to detect it is through a blood test. In the United States, about one in six adults has elevated cholesterol levels.

What the Science Says

In standard medical care, high cholesterol is managed through lifestyle improvements such as healthy eating, maintaining a normal body weight, and regular exercise. When needed, medications are used to lower cholesterol. Certain dietary supplements are also being examined for their possible ability to reduce cholesterol levels.

• Food products that include added plant stanols or sterols are part of standard cholesterol-lowering treatments. Examples include certain fortified juices and butter substitutes. These compounds are also sold in supplement form. While the scientific support is stronger for the food versions, supplements containing stanols or sterols, especially when taken with food, have been shown to help bring cholesterol levels down. Some of these products are allowed by the FDA to carry labels suggesting they may lower heart disease risk when used properly.

• Some products made from soy can provide mild cholesterol-lowering effects. Reviews of multiple studies confirm that soy foods are more effective than soy protein supplements. The cholesterol-reducing capability isn't attributed to soy’s isoflavones, which have hormone-like activity. Still, the benefits, though noticeable, are considerably less than those from prescription medications.

• Research on flaxseed has demonstrated that certain flaxseed forms, like whole seeds and flaxseed lignans, may reduce cholesterol levels. Flaxseed oil does not appear to offer the same benefit. Results seem to be more significant in women, particularly those who are postmenopausal, and in individuals with already high cholesterol levels.

• A summary of garlic supplement studies found that when taken regularly for more than two months, garlic may lead to a small drop in cholesterol levels. However, the reduction is much smaller than what pharmaceutical treatments can achieve.

• Some studies suggest green tea might help reduce cholesterol, though the data for black tea remains inconsistent and less convincing.

• According to the FDA, red yeast rice that includes more than trace amounts of monacolin K—a chemical identical to the drug lovastatin—is deemed an unapproved drug and cannot legally be sold as a supplement. While red yeast rice could help decrease cholesterol levels, it may also bring on side effects very similar to those of lovastatin, including potential interactions with other medications.

• Certain supplements, including chromium, vitamin C, artichoke extract, hibiscus, coenzyme Q10, and selenium, have been studied but haven’t shown promising outcomes for cholesterol control. Likewise, research hasn’t conclusively proven that policosanol or guggulipid are effective in lowering cholesterol levels.

Side Effects and Risks

• It's crucial to follow your health care provider’s advice about cholesterol treatment. Supplements should not replace any drugs your doctor has prescribed. While items such as soy or garlic may help marginally, they are far less potent than prescribed medications.

• Some red yeast rice supplements might contain citrinin, a harmful substance that could damage the kidneys.

• Always read supplement labels carefully and use them as directed. The label “natural” doesn’t automatically mean something is safe. Using overly high doses or combining supplements with medications can lead to serious problems. In addition, most supplements have not undergone safety testing for use during pregnancy, breastfeeding, or childhood.

For More Information

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Know the Science

The National Center for Complementary and Integrative Health (NCCIH), in collaboration with the National Institutes of Health (NIH), provides resources to help individuals better understand science-based health information. The "Know the Science" initiative offers tools such as interactive guides, educational videos, and other materials to help make informed decisions.

Topics covered include how medical research is conducted, how to interpret scientific journal articles, and how clinical trials work.

PubMed®

PubMed®, maintained by the National Library of Medicine, offers summaries of articles from a wide range of scientific and medical journals. NCCIH also offers guidance on how to use PubMed to find information on complementary and integrative health practices.

This material is in the public domain and may be copied freely.

This content is intended for educational purposes only. It should not replace advice from your health care provider. Decisions about treatment should be made together with your provider. Mention of any supplement or treatment does not represent an endorsement by NCCIH.