Red clover, known scientifically as Trifolium pretense, is an herbaceous perennial plant that originates from Europe and northern Africa. It is a close relative of the more familiar white clover, although the flowers of red clover are dark pink in color.
Red clover is a common animal fodder, and it also has a variety of uses in herbal medicine. Many preparations of red clover are available including teas, capsules, tablets and liquid extracts. The flowers are popular as a stand-alone ingredient for herbal tea or as one of many ingredients in an herbal blend. In addition to their wonderful flavor, they provide many medicinal qualities as well.
Red clover tea contains a number of active substances that provide significant benefits. Red clover tea generally does not cause serious side effects in the dosages recommended by manufacturers. The most common side effects of red clover tea include headaches, rashes and nausea. You can read more about red clover side effects here.
What are the Benefits of Drinking Red Clover Tea
Red clover contains significant amounts of compounds known as isoflavones. They are chemically similar to estrogen and therefore have effects similar to those of estrogen. The specific isoflavones in red clover that provide the greatest health benefits include irilone and pratensein.
A 1998 study published in Proceedings of the Society for Experimental Biology and Medicine analyzed the mechanism of action for red clover extract. It showed that they are estrogen agonists since they bind to the estradiol receptors in mammalian cells. This study also classified red clover extract as an anti-progestin, meaning that it inhibits the action of the hormone progesterone.
Some studies show that the isoflavones in red clover may provide protection against heart disease. A 2000 study in Atherosclerosis found an association between these isoflavones and HDL cholesterol levels, commonly known as “good” cholesterol. The subjects in this study included both pre and post-menopausal women. Another study published in a 1999 issue of the Journal of Clinical Endorinol Health showed that red clover supplements made the arteries of menopausal women stronger and more flexible, a condition known medically as arterial compliance. Red clover may also thin the blood, which improves blood flow and prevents blood clots from forming.
One of the most promising aspects of red clover is its use in the treatment of cancer. Its stimulating effects on the immune system are one benefit; another is its phytoestrogen compounds that can retard or even kill some types of cancer cells.
The estrogen-like effects of isoflavones mean that red clover tea may help prevent some types of cancer, while contributing to the growth of other types. A 1988 study in Cancer Research showed some preliminary evidence that isoflavones can prevent cancer cells from growing in test tubes. The Medical Journal of Australia published a 1997 study that describes the role that the isoflavones in red clover may play in preventing endometrial and prostate cancer. On the other hand, a 2001 study in the Journal of the British Menopause Society suggests a link between isoflavones and breast cancer.
Estrogen levels decrease during menopause, which increases a woman’s risk of losing bone mass. This condition is known as osteoporosis, and is a routine consequence of menopause. A 2007 study in Phytotherapy Research suggests that an extract of red clover may reduce the progression of osteoporosis in post-menopausal women. This extract may also increase the density of minerals in the bones for pre-menopausal women. This evidence is still preliminary, so more research is required for the effects of red clover extract on osteoporosis.
Red clover contains resin, a substance helpful to the respiratory system. Resin is a traditional treatment for congestion and cough due to its anti-microbial, expectorating, and warming properties.
A substance called coumarin, used to produce the anticoagulant drug Coumadin, is found in red clover as well as a number of other plants. Although the anti-coagulant properties of red clover are mild compared to those of Coumadin, those taking any blood thinners should be cautious of taking red clover products in combination with medication.
Isoflavones in red clover mimic the effects of estrogen, which explains why herbalists have traditionally used it in cases of chronic miscarrying and infertility for centuries. Red clover is also considered by some to decrease the ill effects of menopause. It should be noted that increasing estrogen levels is not always a good thing and should be avoided when breast cancer, endometriosis or uterine fibroid are an issue.
The most common use of red clover tea in herbal medicine is the relief of menopause symptoms. Red clover also has a long history in herbal medicine for relieving the symptoms of menopause, which is primarily provided by isoflavones such as irilone and pratensein.
Some studies including one issued in the Journal of the American Medical Association published the results of a well-controlled study on Promensil, a preparation of red clover extract that contains a high concentration of isoflavones. This study showed that Promensil reduced the severity of hot flashes in menopausal women as compared to a placebo. Red clover tea also has traditional uses in regulating the menstrual cycle and balancing the pH level in the vagina, which can aid in conception.
Red Clover for Fertility
Red clover is used in herbal medicine to improve the chances of conception, primarily by regulating the menstrual cycle and the pH level of the vagina. The Journal of Animal Science published a study in 1995 showing that red clover increased the weight of the uterus and circumference of the teats in pregnant ewes. These changes were attributed to the stimulation of estradiol receptors by the isoflavones in red clover.
A 2006 study published in the Journal of Agricultural and Food Chemistry examined the chemicals in red clover that produce estrogen-like effects. This study was a phase II clinical trial, meaning the purpose of the trial was to establish the testing protocol. The study identified 22 such chemicals and qualitatively measured 20 of these, including the isoflavones biochanin A, daidzein, formononetin and genistein.
The results of a double-blind, placebo-controlled trial on red clover extract were published in a 2004 issue of Breast Cancer Research and Treatment. The purpose of the study was to determine the effects of isoflavone supplements derived from red clover on the breast density of women. The study involved 205 women with the Wolfe DY or P2 breast density patterns, which indicate a high risk of breast cancer. The study showed that the isoflavone supplements significantly reduced the breast density of both groups compared to the placebo.
Learn more about the medicinal uses of Red Clover along with dosage and administration instruction.
Thinking of using Red Clover as a vitamin or supplement? Find out what WebMD has to say about using Red Clover.
Learn about the science of Red Clover for Alternative Medicine at the National Center for Complementary and Alternative Medicine.