Red clover, a wild plant that is used for grazing cattle and other animals, has also been used medicinally to treat a wide array of conditions. These have included cancer, mastitis (inflammation of the breast), joint disorders, respiratory problems, and skin inflammations, such as psoriasis and eczema. Traditionally, red clover was thought to "purify" the blood by acting as a diuretic (helping the body get rid of excess fluid) and expectorant (helping clear lungs of mucous), improving circulation, and helping cleanse the liver.
Modern scientific tests have shown that red clover contains isoflavones, plant-based chemicals that produce estrogen-like effects in the body. Isoflavones have shown potential in the treatment of a number of conditions associated with menopause, such as hot flashes, cardiovascular health, and osteoporosis. However, as researchers have become aware of the side effects of taking estrogen, there is also some concern about the safety of isoflavones.
Red clover is a perennial herb that commonly grows wild in meadows throughout Europe and Asia, and has now been naturalized to grow in North America. The red flowers at the end of the branched stems are usually dried for therapeutic use.
Red clover is a source of many valuable nutrients including calcium, chromium, magnesium, niacin, phosphorus, potassium, thiamine, and vitamin C. Red clover is also considered to be one of the richest sources of isoflavones (water-soluble chemicals that act like estrogens and are found in many plants).
Treatment
Cardiovascular health
Red clover may help protect against heart disease in several ways. Red clover isoflavones have been associated with an increase in "good" high-density lipoprotein (HDL) cholesterol in pre- and postmenopausal women, but other studies show conflicting evidence. One study found that menopausal women taking red clover supplements had more flexible and stronger arteries (called arterial compliance), which can help prevent heart disease. Red clover may also have blood-thinning properties, which keeps blood clots from forming. It appears to improve blood flow.
Menopause
Several studies of a proprietary extract of red clover isoflavones suggest that it may significantly reduce hot flashes in menopausal women. The largest study, however, showed no such effect.
Osteoporosis
Menopause increases a woman's risk for developing osteoporosis (significant bone loss). Some studies suggest that a proprietary extract of red clover isoflavones may slow bone loss and even boost bone mineral density in pre- and perimenopausal women, but the evidence is preliminary.
Cancer
Based on its traditional use for cancer, researchers have begun to study isoflavones from red clover, and there is preliminary evidence that they may prevent the growth of cancer cells or kill cancer cells in test tubes. It's been proposed that red clover may help prevent some forms of cancer, such as prostate and endometrial cancer. However, given the herb's estrogen-like effects, it might also contribute to the growth of some cancers, just as estrogen does. Until further research is done, red clover cannot be recommended to prevent cancer and should be avoided in women with a history of breast cancer.
Other uses
Traditionally, red clover ointments have been applied to the skin to treat psoriasis, eczema, and other rashes. Red clover also has a history of use as a cough remedy for children.
Red clover is available in a variety of preparations, including teas, tinctures, tablets, capsules, liquid extract, and extracts standardized to specific isoflavone contents. It can also be prepared as an ointment for topical application.
Pediatric
Red clover has a history of short-term use as a cough remedy for children. Isolated red clover isoflavone products are very different than the whole herb, however, and are not recommended for children. Do not give a child red clover without talking to your pediatrician first.
Adult
Although dosage and administration will vary from individual to individual, general guidelines are as follows:
- Dried herb (used for tea): 1 - 2 tsp dried flowers or flowering tops steeped in 8 oz. hot water for 1/2 hour; drink 2 - 3 cups daily
- Powdered herb (available in capsules): 40 - 160 mg per day, or 28 - 85 mg of red clover isoflavones
- Tincture (1:5, 30% alcohol): 60 - 100 drops (3 - 5 mL) three times per day; may add to hot water as a tea
- Fluid Extract (1:1): 1 mL three times per day; may add to hot water as a tea
- Standardized red clover isoflavone extracts: directions on product labels should be carefully followed
- Topical treatment (such as for psoriasis or eczema): an infusion, liquid extract, or ointment containing 10 - 15% flowerheads; apply as needed unless irritation develops. Do not apply to an open wound without a doctor's supervision.
Although some red clover isoflavones are being studied for the treatment of a variety of conditions, it is important to remember that extracts of red clover isoflavones are very different from the whole herb -- in fact, they represent only a small portion of the entire herb in a highly concentrated form.
Side Effects
No serious side effects from red clover have been reported in humans. General side effects can include headache, nausea, and rash. However, infertility has been noted in grazing animals that consume large amounts of red clover.
Pregnancy and Breastfeeding
Pregnant or breastfeeding women should not take red clover.
Red clover may interfere with the body's ability to process some drugs that are broken down by liver enzymes. For that reason, you should check with your doctor before taking red clover.
Estrogens, hormone replacement therapy, birth control pills -- Red clover may alter the effects of any drugs containing hormones or derivatives of hormones, as well as the levels of hormones in the body.
Tamoxifen -- Red clover may interfere with tamoxifen.
Anticoagulants (blood thinners) -- Red clover may enhance the effect of these drugs, as well as herbs and supplements that have blood-thinning effects (such as ginkgo, ginger, garlic, and vitamin E).
Diabetes drugs -- Red clover may lower blood sugar and alter the effects of drugs taken to control diabetes.
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