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.
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).
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.
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.
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
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.
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
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.
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)
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
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%
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
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
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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,
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of any of the information contained herein, including any injury and/or damage
to any person or property as a matter of product liability, negligence, or
otherwise. No warranty, expressed or implied, is made in regard to the contents
of this material. No claims or endorsements are made for any drugs or compounds
currently marketed or in investigative use. This material is not intended as a
guide to self-medication. The reader is advised to discuss the information
provided here with a doctor, pharmacist, nurse, or other authorized healthcare
practitioner and to check product information (including package inserts)
regarding dosage, precautions, warnings, interactions, and contraindications
before administering any drug, herb, or supplement discussed