Like peas and beans, red clover belongs to the family of plants called legumes. Red clover contains substances called isoflavones. Isoflavones are phytoestrogens—compounds similar to the female hormone estrogen.
Historically, red clover was used for a variety of conditions including asthma, whooping cough, cancer, and gout. Today, isoflavone extracts from red clover are most often used as dietary supplements for menopausal symptoms, high cholesterol, or osteoporosis.
The flowering tops of the red clover plant are used to prepare extracts available in tablets or capsules, as well as in teas and liquid forms.
Red clover has not been clearly shown to be helpful for any health condition.
Most research indicates that taking red clover does not relieve menopause symptoms such as hot flashes.
The National Center for Complementary and Integrative Health (NCCIH) is supporting research to develop better methods of identifying active components in red clover and to evaluate possible interactions of red clover with medications.
No serious side effects have been reported in studies that evaluated red clover for various health conditions for up to a year.
Because red clover contains estrogen-like compounds, there’s a possibility that long-term use would increase the risk of women developing cancer of the endometrium (the lining of the uterus). However, short-term studies of women who have taken red clover have not shown harmful changes in the uterine lining.
Red clover may not be safe for women who are pregnant or breastfeeding, for children, or for women who have breast cancer or other hormone-sensitive cancers.