Red Clover

Background

• Like peas and beans, red clover is a legume. It is native to Europe, central Asia, and northern Africa, and is also grown in many other areas.
• Red clover contains substances called isoflavones that are structurally similar to estrogen. Dietary supplements containing red clover are promoted for women’s health conditions.

How Much Do We Know?

• Red clover has been studied in people, but the research hasn’t shown conclusive evidence of benefits for any health condition. Some of the research on red clover for hot flashes associated with menopause was not high in quality, findings on cholesterol levels were conflicting, and only a few studies have been done on bone density.

What Have We Learned?

• Studies on the effects of red clover on hot flashes associated with menopause have had inconsistent results, and some of the studies had a high risk of bias.
• Red clover may have a beneficial effect on cholesterol levels in postmenopausal women, but more research is needed before definite conclusions can be reached.
• Only a small number of studies have been done on the effects of red clover on bone density in postmenopausal women, and the results have been inconsistent.

What Do We Know About Safety?

• Red clover extracts have been used in clinical studies for as long as 2 years with apparent safety, and they appear to be well tolerated.
• Red clover supplements may be unsafe for use during pregnancy or while breastfeeding.

Keep in Mind

• Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.
• If you take any type of medicine, talk with your health care provider before using any herbal product; some herbs and medicines interact in harmful ways.
• Federal Regulation of Herbal Products
  • Depending on what’s in them, how they’re intended to be used, and how they’re administered (orally or topically), herbal products are regulated in a variety of ways. Many herbal products intended for oral use are marketed as dietary supplements. The regulatory paths for making and distributing dietary supplements are different than those for drugs.
  • Unlike drugs, dietary supplements are not approved by the U.S. Food and Drug Administration (FDA) before they are sold to the public. When public health concerns arise about the safety of a dietary supplement or an ingredient including an herb, the FDA can take action to protect the public. Manufacturers and distributors of supplements are responsible for evaluating the safety and labeling of their products before marketing to ensure that they meet all regulatory requirements. 

For More Information

• Using Dietary Supplements Wisely
• Know the Science: How Medications and Supplements Can Interact
• Know the Science: How To Make Sense of a Scientific Journal Article

Key References