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Photo copyright Steven Foster
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Botanical name: Medicago sativa
Parts used and where grown: Alfalfa, also known as lucerne, is
a member of the pea family and is native to western Asia and the eastern Mediterranean region.
Alfalfa sprouts have become a popular food. Alfalfa herbal supplements primarily use the dried
leaves of the plant. The heat-treated seeds of the plant have also been used.
Alfalfa has been used in
connection with the following conditions (refer to the individual
health concern for complete information):
Historical or traditional use (may or may not
be supported by scientific studies): Many years ago, traditional Chinese
physicians used young alfalfa leaves to treat disorders of the digestive tract.1
Similarly, the Ayurvedic physicians of India
prescribed the leaves and flowering tops for poor digestion. Alfalfa was also considered
therapeutic for water retention and arthritis. North American Indians recommended alfalfa to
treat jaundice and to encourage blood clotting.
Although conspicuously absent from many classic textbooks on herbal medicine, alfalfa did
find a home in the texts of the Eclectic physicians (19th-century physicians in the United
States who used herbal therapies) as a tonic for
indigestion, dyspepsia, anemia, loss of appetite, and poor assimilation of
nutrients.2 These physicians also recommended the alfalfa plant to stimulate
lactation in nursing mothers, and the seeds were made into a poultice for the treatment of
boils and insect bites.
Active constituents: While the medicinal benefits of alfalfa
are poorly understood, the constituents in alfalfa have been extensively studied. The leaves
contain approximately 2–3% saponins.3 Animal studies suggest that these
constituents block absorption of cholesterol and
prevent the formation of atherosclerotic plaques.4 One small human trial found that
120 grams per day of heat-treated alfalfa seeds for eight weeks led to a modest reduction in
cholesterol.5 However, consuming the large amounts of alfalfa seeds (80–120
grams per day) needed to supply high amounts of these saponins may potentially cause damage to
red blood cells in the body.6 Herbalists also claim that alfalfa may be helpful for
people with diabetes. But while high amounts of a water
extract of the leaves led to increased insulin release in animal studies, there is no evidence
that alfalfa would be useful for the treatment of diabetes in humans.7
Alfalfa leaves also contain flavones, isoflavones, sterols, and coumarin derivatives. The
isoflavones are thought to be responsible for the estrogen-like effects seen in animal
studies.8 Although this has not been confirmed with human trials, alfalfa is
sometimes used to treat menopause symptoms.
Alfalfa contains protein and vitamin A, vitamin B1, vitamin B6, vitamin C, vitamin E, and
vitamin K. Nutrient analysis demonstrates the presence of
calcium, potassium, iron, and zinc.
How much is usually taken? Dried alfalfa leaf is available as
a bulk herb, and in tablets or capsules. It is also available in liquid extracts. No
therapeutic amount of alfalfa has been established for humans. Some herbalists recommend
500–1,000 mg of the dried leaf per day or 1–2 ml of tincture three times per
day.9
Are there any side effects or interactions? Use of the dried
leaves of alfalfa in the amounts listed above is usually safe. There have been isolated
reports of people who are allergic to alfalfa. Ingestion of very large amounts (the equivalent
of several servings) of the seed and/or sprouts has been linked to the onset of systemic lupus erythematosus (SLE) in animal studies.10
It has also been linked to the reactivation of SLE in people consuming alfalfa
tablets.11 SLE is an autoimmune illness characterized by inflamed joints and a high
risk of damage to kidneys and other organs. The chemical responsible for this effect is
believed to be canavanine.
At the time of writing, there were no well-known drug interactions
with alfalfa.
References:
1. Briggs C. Alfalfa. Canadian Pharm J 1994;Mar:84–5,
115.
2. Castleman M. The Healing Herbs. Emmaus, PA: Rodale Press,
1991, 37–9.
3. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients
Used in Food, Drugs, and Cosmetics, 2d ed. New York: John Wiley & Sons, 1996,
13–5.
4. Story JA. Alfalfa saponins and cholesterol interactions. Am J Clin
Nutr 1984;39:917–29.
5. Molgaard J, von Schenck H, Olsson AG. Alfalfa seeds lower low density
lipoprotein cholesterol and apolipoprotein B concentrations in patients with type II
hyperlipoproteinemia. Atherosclerosis 1987;65:173–9.
6. Malinow MR, Bardana EJ, Goodnight SH. Pancytopenia during ingestion of
alfalfa seeds. Lancet 1981;1(8220 Pt 1):615.
7. Foster S, Tyler VE. Tyler’s Honest Herbal. New York:
Haworth Press, 1999, 23–5.
8. Shemesh M, Lindrer HR, Ayalon N. Affinity of rabbit uterine oestradiol
receptor for phyto-oestragens and its use in competitive protein-binding radioassay for plasma
coumestrol. J Reprod Fertil 1972;29:1–9.
9. Foster S. Herbs for Your Health. Loveland, CO: Interweave
Press, 1996, 2–3.
10. Malinow MR, Bardana EJ, Profsky B, et al. Systemic lupus
erythematosus-like syndrome in monkeys fed alfalfa sprouts: Role of a nonprotein amino acid.
Science 1982;216:415–7.
11. Roberts JL, Hayashi JA. Exacerbation of SLE associated with alfalfa
ingestion. New Engl J Med 1983;308:1361.
Copyright © 2002 Healthnotes, Inc. All rights reserved.
www.healthnotes.com
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The information presented in Healthnotes is for informational
purposes only. It is based on scientific studies (human, animal, or in vitro),
clinical experience, or traditional usage as cited in each article. The results reported may
not necessarily occur in all individuals. For many of the conditions discussed, treatment with
prescription or over-the-counter medication is also available. Consult your doctor,
practitioner, and/or pharmacist for any health problem and before using any supplements or
before making any changes in prescribed medications. Information expires December 2003.
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