for Adult Medicine
Alfalfa (Medicago sativa)
Be aware that the U.S. Food and Drug Administration does not strictly regulate
herbs and dietary supplements. There is no guarantee of strength, purity
or safety of products containing or claiming to contain alfalfa. Decisions
to use herbs or supplements should be carefully considered. Individuals using
prescription drugs should discuss taking herbs or supplements with a pharmacist
or health care professional before starting.
Scientists have studied alfalfa for the following health problems:
Alfalfa may have cholesterol-lowering effects. There is a scientific basis,
based on multiple animal studies, that alfalfa lowers cholesterol. However,
there is only limited research in humans specifically using alfalfa for this
purpose. Larger studies are needed to determine if there is any benefit from
alfalfa for this condition.
Atherosclerosis (clogged arteries)
Some animal studies suggest that alfalfa may provide benefits for treating
atherosclerosis (clogged arteries). However, no studies have been performed
in humans. Therefore, at this time, it is unclear whether alfalfa provides
any benefits in people with atherosclerosis.
Studies in rats report that alfalfa lowers blood sugar levels. However, it
is not clear what effects alfalfa has on blood sugar levels in humans.
Alfalfa has been suggested for many other uses, based on tradition or
on scientific theories. However, these uses have not been thoroughly studied
in humans, and there is limited scientific evidence about safety or
effectiveness. Some of these suggested uses are for conditions that are
potentially very serious and even life-threatening. You should consult with
a health care professional before taking alfalfa for any unproven use.
Breast milk stimulant
Diuresis (urine production)
Idiopathic thrombocytopenic purpura (a platelet disorder) Indigestion
Radiation-induced skin damage
Vitamin C deficiency
People should avoid alfalfa if they have a known allergy to alfalfa or any
member of the Fabaceae or leguminous plant families. Alfalfa should be used
carefully in individuals allergic to grass. Signs of allergy might include
rash, itching or shortness of breath.
Alfalfa is reported as well tolerated by most individuals, but serious side
effects are possible. Some people may experience stomach discomfort, including
diarrhea, gas or larger and more frequent stools. Dermatitis (red and inflamed
skin) has been reported. This reaction may be caused by alfalfa allergy.
Alfalfa may also lower blood sugar levels. Caution is advised if you take
prescription drugs to control your blood sugar levels.
Use of alfalfa has been associated with lupuslike effects, such as antinuclear
antibodies in the blood, muscle pains, fatigue, abnormal immune system function
and kidney problems. As a result, people with a history of lupus or a family
history of lupus should avoid alfalfa supplements. If you experience any
lupuslike symptoms while taking alfalfa, you should consult a qualified health
care professional immediately. In theory, alfalfa may also increase the risk
of blood clots. If you use anticoagulant drugs (blood thinners) and are
considering using alfalfa, you should discuss this with a health care
professional. Abnormal blood cell counts have also been reported. This could
lead to a risk of anemia or could cause bleeding. In theory, alfalfa may
aggravate thyroid disease or gout. Alfalfa may also lower potassium levels
and may possess estrogenlike properties.
Contamination of alfalfa products with dangerous bacteria has been reported.
Such infections may be serious and may lead to death. Be aware that many
alfalfa extracts contain high levels of alcohol and should be avoided when
driving or operating heavy machinery.
Pregnancy And Breast-Feeding
Alfalfa cannot be recommended during pregnancy or breast-feeding because
of the risk of birth defects or spontaneous abortion, although it is believed
to be safe in amounts normally found in food. Be aware that many extracts
contain high levels of alcohol and should be avoided during pregnancy.
Interactions with drugs, supplements and other herbs have not been thoroughly
studied. The interactions listed below have been reported in scientific
publications. If you are taking prescription drugs, speak with a health care
professional or pharmacist before using herbs or dietary supplements.
Interactions With Drugs
Alfalfa may lower blood sugar levels. Caution is advised if you are also
taking prescription drugs that may lower blood sugar levels. Patients taking
oral drugs for diabetes or using insulin should be monitored closely by a
health care professional while using alfalfa. Dosing adjustments may be
necessary. Alfalfa may also lower cholesterol excessively if used with other
cholesterol-lowering drugs, such as atorvastatin (Lipitor). In theory, alfalfa
may increase the risk of blood clotting, making anticoagulants (blood thinners),
such as warfarin (Coumadin), less effective. Alfalfa could possibly increase
the risk of severe sunburn when used with other drugs that increase the tendency
to burn, such as chlorpromazine (Thorazine). In theory, alfalfa may increase
side effects of some drugs that contain estrogens, such as birth control
pills or hormone replacement therapies.
It is also possible that alfalfa may alter the function of the thyroid. If
you take drugs to treat thyroid disease and are considering using alfalfa,
you should discuss this with a health care professional, because additional
monitoring may be necessary. Be aware that many extracts contain high levels
of alcohol and may cause nausea or vomiting when taken with metronidazole
(Flagyl) or disulfiram (Antabuse).
Interactions With Herbs And Dietary
Alfalfa may lower blood sugar levels. People using other herbs or supplements
that may alter blood sugar levels, such as bitter melon (Momordica charantia),
should be monitored closely by a health care professional while using alfalfa.
Dosing adjustments may be necessary. Alfalfa may have cholesterol-lowering
properties. These effects may be increased if used with other supplements
that possess similar properties, such as red yeast. Alfalfa may contain vitamin
K and, as a result, may increase the likelihood of blood clots. In theory,
alfalfa may possess estrogenlike properties and may increase side effects
if used with other herbs, such as red clover (Trifolium pratense), that have
estrogenlike effects. In theory, alfalfa may lessen the effects of supplements
such as iron or vitamin E.
The doses listed below are based on scientific research, publications
or traditional use. Because most herbs and supplements have not been thoroughly
studied or monitored, safety and effectiveness may not be proven. Brands
may be made differently, with variable ingredients even within the same brand.
Combination products often contain small amounts of each ingredient and may
not be effective. Appropriate dosing should be discussed with a health care
professional before starting therapy; always read the recommendations on
a product's label. The dosing for unproven uses should be approached cautiously,
because scientific information is limited in these areas.
Safety of use beyond eight weeks has not been studied. There are no standard
or well-studied doses of alfalfa, and many different doses are used
Adults (Aged 18 Or Older)
Tablets: A dose of two tablets (one gram each) of Cholestaid (esterin processed
alfalfa) taken by mouth three times daily for up to two months, then one
tablet three times daily, has been recommended by the manufacturer.
Dried herb: A dose of five to 10 grams of dried herb taken by mouth three
times daily has been used.
Liquid extract: A dose of five to 10 milliliters (one to two teaspoonfuls)
of a 1:1 solution in 25 percent alcohol taken by mouth three times daily
has been used.
Seeds: For treating high cholesterol, a dose of 40 grams of heated seeds
prepared three times daily and taken by mouth with food has been used.
Children (Younger Than 18)
There are not enough scientific data to recommend alfalfa supplements for
use in children, and alfalfa is not recommended because of potential side
Alfalfa has been suggested as a treatment for many conditions. However, there
is not enough scientific evidence at this time to support the use of alfalfa
for any medical condition. Alfalfa may lower cholesterol levels. Use of alfalfa
may increase the risk of blood clots and may lower blood sugar levels. People
taking anticoagulants (blood thinners) and those with diabetes who take oral
drugs or use insulin to control their sugar levels should use alfalfa cautiously.
Alfalfa should be avoided in pregnant or breast-feeding women and in children
in amounts larger than commonly found in foods. Safety of use beyond eight
weeks has not been studied. Consult a health care professional immediately
if you have any side effects.
The information in this monograph was prepared by the professional staff
at Natural Standard, based on thorough systematic review of scientific evidence.
The material was reviewed by the Faculty of the Harvard Medical School with
final editing approved by Natural Standard.
Natural Standard: An organization that produces scientifically based reviews
of complementary and alternative medicine (CAM) topics
National Center for Complementary and Alternative Medicine (NCCAM): A division
of the U.S. Department of Health & Human Services dedicated to research
Selected Scientific Studies: Alfalfa
Natural Standard reviewed more than 165 articles to prepare the professional
monograph from which this version was created.
Some of the more recent studies are listed below:
Anonymous. From the Centers for Disease Control and Prevention. Outbreaks
of Escherichia coli O157:H7 infection associated with eating alfalfa sprouts:
Michigan and Virginia, June-July 1997. JAMA 1997;278(10):809-810.
Backer HD, Mohle-Boetani JC, Werner SB, et al. High incidence of extra-intestinal
infections in a Salmonella Havana outbreak associated with alfalfa sprouts.
Public Health Rep 2000;115(4):339-345.
Bengtsson AA, Rylander L, Hagmar L, et al. Risk factors for developing systemic
lupus erythematosus: a case-control study in southern Sweden. Rheumatology
(Oxford) 2002;May, 41(5):563-571.
Boue SM, Wiese TE, Nehls S, et al. Evaluation of the estrogenic effects of
legume extracts containing phytoestrogens. J Agric Food Chem 2003;Apr 9,
Farnsworth NR. Alfalfa pills and autoimmune diseases. Am J Clin Nutr
Lanza A, Tava A, Catalano M, et al. Effects of the Medicago scutellata trypsin
inhibitor (MsTI) on cisplatin-induced cytotoxicity in human breast and cervical
cancer cells. Anticancer Res 2004;24(1):227-233.
Liao CH, Fett WF. Isolation of Salmonella from alfalfa seed and demonstration
of impaired growth of heat-injured cells in seed homogenates. Int J Food
Microbiol 2003;May 15, 82(3):245-253.