Red Clover
What is it? Overview Usage Side Effects and Warnings

What is Red Clover?

Red clover has been cultivated since ancient times, primarily to provide a favorite grazing food for animals. But, like many other herbs, red clover was also a valued medicine. Although it has been used for many purposes worldwide, the one condition most consistently associated with red clover is cancer. Chinese physicians and Russian folk healers also used it to treat respiratory problems.

In the nineteenth century, red clover became popular among herbalists as an "alternative" or "blood purifier." This medical term, long since defunct, refers to an ancient belief that toxins in the blood are the root cause of many illnesses. Cancer, eczema, and the eruptions of venereal disease were all seen as manifestations of toxic buildup.

Red clover was considered one of the best herbs to...

Evidence is inconsistent on whether red clover isoflavones are helpful for menopausal hot flashes , 1 with the largest trial failing to find benefits. 2 A small and poorly reported double-blind, placebo-controlled study provides weak evidence that red clover isoflavones might be helpful for cyclic mastalgia . 3 Although soy and, possibly, soy isoflavones 4 have been found to reduce cholesterol levels, two trials enrolling a total of more than 100 women failed to find red clover isoflavones helpful for this purpose. 5 However, in a double-blind, placebo-controlled comparative study of 80 people (both men and women), a red clover extract modified to be rich in biochanin did reduce LDL (“bad”) cholesterol, while one enriched in formononetin did not. 6 One very small...

Safety Issues

Red clover is on the Food and Drug Adminstration's Generally Recognized as Safe (GRAS) list and is included in many beverage teas. However, detailed safety studies have not been performed.

Because of its blood-thinning and estrogen-like constituents, red clover should not be used by pregnant or nursing women, or women who have had breast or uterine cancer. A study investigating the safety of red clover in women with a family history of breast cancer found no changes in breast density or thickness of the uterine lining over a three-year period, which is somewhat reassuring. 7 However, the study was much too short to determine red clover's long-term effect on cancer risk. Safety in young children or those with severe liver or kidney disease has also not been...