Red Clover

Red clover, a wild plant used as grazing food for cattle and other livestock, has also been used medicinally to treat a wide array of conditions. These have included cancer, mastitis (inflammation of the breast), joint disorders, jaundice, bronchitis, spasmodic coughing, asthma, and skin inflammations, such as psoriasis and eczema. Red clover is thought to "purify" the blood by promoting urine and mucous production, improving circulation, and stimulating the secretion of bile. Recently, specific chemicals in red clover -- known as isoflavones -- have been isolated and tested for their effectiveness in treating a variety of conditions. Although isolated isoflavone products are very different from the whole herb, they have shown promise in the treatment of a number of conditions associated with menopause, such as hot flashes, cardiovascular health, and the bone loss associated with osteoporosis.

Plant Description

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 considered to be the source of its medicinal properties and are usually dried for therapeutic use.

Medicinal Uses and Indications

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

Menopause increases a woman's risk for developing cardiovascular disease. Supplementation with red clover isoflavones has been associated with a sizeable increase in high-density lipoprotein (HDL) cholesterol, or "good" cholesterol in pre- and postmenopausal women, leading some researchers to believe that these isoflavones may help protect against cardiovascular disease. Other studies, however, have refuted this finding. Interestingly, one recent study found that menopausal women taking red clover supplements experienced a significant improvement in arterial compliance (a measure of the strength and resilience of the arterial walls). Arterial compliance diminishes during menopause and may increase a woman's risk for heart disease.

Menopause

While not all studies are thoroughly convincing, several studies of a proprietary extract of red clover isoflavones suggest that it may significantly reduce hot flashes in menopausal women.

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.

Cancer

The isoflavones isolated from red clover have been studied for their effectiveness in treating some forms of cancer. It is thought that the isoflavones prevent the proliferation of cancer cells and that they may even destroy cancer cells. Laboratory and animal studies have found that red clover isoflavones may protect against the growth of breast cancer cells. This is surprising because estrogens (and isoflavones have estrogenic properties) have generally been thought to stimulate the growth of breast cancer in women. Until further research has been conducted and more information is available, the use of red clover isoflavones or other red clover products should probably be avoided in women with a history of breast cancer.

Other Uses

Traditionally, red clover ointments have been applied to the skin to treat conditions such as psoriasis, eczema, and other rashes. Red clover also has a history of use as a cough remedy for children.

Dosage and Administration

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.

Adult

Although dosage and administration will vary from individual to individual, general guidelines are as follows:

Dried herb (used for tea): 1 to 2 tsp dried flowers or flowering tops steeped in 8 oz hot water for 1/2 hour; take 2 to 3 cups daily
Powdered herb (available in capsules): 2 to 6 capsules (500 mg each) per day
Tincture (1:5, 30% alcohol): 60 to 100 drops (3 to 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 to 15% flowerheads

As mentioned above, isolated red clover isoflavones have shown promise in the treatment of a variety of conditions. It is important to remember, however, 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.

Precautions

Side Effects

No serious adverse side effects from red clover have been reported in humans. However, infertility has been noted in grazing animals that consume large amounts of red clover.

Pregnancy and Breastfeeding

The use of red clover is not recommended for pregnant or breastfeeding women.

Interactions and Depletions

Because of the estrogen-like properties in red clover isoflavones, women with a history of breast cancer should avoid red clover (some studies suggest that synthetic and/or natural estrogens may increase the risk of breast cancer). Red clover isoflavones should be used with caution, if at all, by people receiving hormone therapy (including birth control pills) containing estrogen, progesterone, androgen or any derivatives of these hormones. Because of the increased risk of bleeding associated with red clover, individuals taking blood-thinning medications (such as warfarin or aspirin) or blood-thinning herbs and supplements (such as ginkgo, ginger, garlic, and vitamin E) should avoid red clover.

Supporting Research

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Baber RJ, Templeman C, Morton T, Kelly GE, West L. Randomized, placebo-controlled trial of an isoflavone supplement and menopausal symptoms in women. Climacteric. 1999b;2(2):85-92.

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Review Date: June 2001

Reviewed By: Participants in the review process include: Jacqueline A. Hart, MD, Department of Internal Medicine, Newton-Wellesley Hospital, Harvard University and Senior Medical Editor Integrative Medicine, Boston, MA; R. Lynn Shumake, PD, Director, Alternative Medicine Apothecary, Blue Mountain Apothecary & Healing Arts, University of Maryland Medical Center, Glenwood, MD; David Winston, Herbalist, Herbalist and Alchemist, Inc., Washington, NJ.

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