Humans, too, find red clover a tasty and nutritious addition to their menus (after all, it’s a member of the pea family). Red clover blossoms can be scattered, crouton-like, over a salad, and its leaves can be lightly steamed and served as a side dish. (Red clover is also the source of a popular and flavorful honey.)
And, if its dietary attributes don’t provide an adequate excuse to grow a clump or two of red clover in your yard, keep in mind that generations of physicians and native healers have used this herb for treating whooping cough, bronchitis, asthma, menopausal symptoms, premenstrual syndrome, high cholesterol, osteoporosis, prostate enlargement, and even cancer.
Red Clover’s Distinguished History
Way back in 1890, before the age of high-powered drugs and similarly potent patent attorneys, Parke-Davis (now a subsidiary of Pfizer) introduced Syrup Trifolium, a formulation of red clover, prickly ash, burdock root, poke root, Oregon grape, and potassium iodide. Syrup Trifolium was marketed as a blood purifier and—for a brief time—found some utility in cancer therapy.
In 1898, red clover was listed in King’s American Dispensatory, the bible of Eclectic Physicians. Even before then, the Eclectics used red clover blossoms as an alterative and blood purifier, and its inclusion in their Trifolium Compound was the basis for another anti-cancer preparation, the Hoxsey Formula.
In his book, The Green Pharmacy, Dr. James Duke (one of the world’s leading authorities on herbal healing traditions) touted red clover as a cancer preventative and a treatment for menopausal symptoms, menstrual cramps, and even as an aid to smoking cessation.
Evidence of Red Clover’s Benefits Is Controversial…but Intriguing
Research has revealed that red clover is a rich source of isoflavones, or “phytoestrogens,” a class of organic compounds with antioxidant and estrogenic properties. These compounds hold promise for a variety of reasons, but, as of 2008, the National Center for Complementary and Alternative Medicine maintained there was insufficient evidence to show that red clover is effective for treating any health condition.
Be that as it may, studies suggest that red clover could be of use in several situations:
Cardiovascular: Red clover’s isoflavones have evoked an increase in HDL cholesterol—the good cholesterol—in some clinical trials, but not in others. In addition, red clover may improve arterial compliance, or elasticity, and its coumarin acts as a mild anticoagulant, or “blood thinner.” All of these properties could prove beneficial for people at risk for heart disease.
PMS and Menopause: Isoflavones bind to estrogen receptors on human cells, providing a weak estrogenic effect in situations where natural estrogen levels have fallen. This has obvious implications for women who suffer from menopausal symptoms (hot flashes, vaginal dryness, moodiness, etc.). Even more compelling is the evidence that phytoestrogens—by blocking the effects of circulating estrogens—exert a protective effect in individuals with estrogen-sensitive tumors (breast, ovarian, prostate, uterine, etc.) However, there is insufficient data to recommend the use of red clover or any phytoestrogen-containing plant in these patients.
Osteoporosis: Estrogen stimulation is important for maintaining bone mass in elderly women. With the decline in estrogen levels that occurs during menopause, isoflavones could slow bone loss by attaching to cellular receptors in bone. Preliminary evidence shows potential benefit, but, again, the data is insufficient.
Cancer: Some studies have suggested that red clover isoflavones inhibit cancer cell growth and/or interfere with angiogenesis (a tumor’s ability to establish a blood supply). However, since isoflavones also exert a weak estrogenic effect, some scientists fear they might actually contribute to the development and growth of estrogen-sensitive cancers. Given the recent evidence of phytoestrogens’ protective effect in estrogen-dependent malignancies, this issue is far from settled.
Red clover appears to be safe for most adults. Individuals who are at risk for or who have been diagnosed with estrogen-sensitive cancers should avoid red clover until more is known about its effects in these settings. In addition, people who take warfarin or other blood thinners should consult their physicians before taking red clover.
- Treating Cancer with Herbs, an Integrative Approach. Michael Tierra.Lotus Press, 2003. Pg 240
- The Green Pharmacy. James A. Duke. Rodale Press, 1997. Pp 325, 328, 399-400
- Tice J, et al. Phytoestrogen supplements for the treatment of hot flashes: the Isoflavone Clover Extract (ICE) study. Journal of the American Medical Association. 2003;290(2):207–214)
- Chedraui P, et al. Effect of Trifolium pratense-derived isoflavones on the lipid profile of postmenopausal women with increased body mass index. Gynecol Endocrinol. 2008;24(11):620-4
- Mueller M, Jungbauer A. Red clover extract: a putative source for simultaneous treatment of menopausal disorders and the metabolic syndrome. Menopause. 2008;15(6):1120-31
- Occhiuto F, et al. Effects of phytoestrogenic isoflavones from red clover (Trifolium pratense L.) on experimental osteoporosis. Phytother Res. 2007;21(2):130-4
- Powles T, et al. Red clover isoflavones are safe and well tolerated in women with a family history of breast cancer. Menopause Int. 2008;14(1):6-12