What is Alfalfa?
Alfalfa (Medicago sativa) is a plant native to the Mediterranean region but widely cultivated elsewhere. It has an age-old reputation as a nutritious food. Alfalfa contains chlorophyll, protein, minerals, and beta-carotene, B vitamins, and vitamins C, E, and K.
Alfalfa has a long history of use as a folk remedy in Europe, China, and India for indigestion, arthritis, bladder problems, high cholesterol, allergic rhinitis and hayfever, and irregular menstruation.
Sources of Alfalfa
Alfalfa is best known as a food. The raw sprouts can be found in the produce section of grocery stores and health food stores.
It is also available in capsule, powder, tablet, and liquid extract forms. Many of these supplements are made from dried alfalfa leaves and/or seeds.
Uses for Alfalfa
- Nutritional Support
- Menopausal Symptoms (e.g. Hot Flashes)
- High Cholesterol
Evidence for Alfalfa
Although preliminary studies with human subjects suggest that alfalfa may lower total and LDL cholesterol, there haven't been any randomized, controlled trials to substantiate these initial findings.
In fact, there haven't been any randomized, controlled human trials on the use of alfalfa for any human health condition.
Alfalfa contains coumestans, which are phytoestrogens. For this reason, alfalfa has been examined in laboratory studies for menopausal symptoms.
The alfalfa plant, especially the seeds, contains an amino acid called L-canavanine. Excess consumption of L-canavanine may cause abnormal blood cell counts, spleen enlargement, or the recurrence of active disease in patients with lupus. Exposing the seeds to extremely high temperatures may prevent this, but it hasn't been confirmed.
People with lupus or a family history of lupus should avoid alfalfa in any form.
Pregnant or nursing women, young children, or people with estrogen sensitive cancers should also avoid alfalfa because of its possible estrogenic effects.
Alfalfa has a high potassium content. People with chronic kidney insufficiency, hypoaldosteronism, or who are using potassium-altering medications should avoid alfalfa to avoid the risk of potentially life-threatening hyperkalemia (too much potassium in the blood).
Some health practitioners recommend that people who are immunocompromised should avoid the sprouts because of the risk of food poisoning.
Potential Drug Interactions
Alfalfa may reduce the effectiveness of "blood-thinning" drugs, such as warfarin (coumadin) because alfalfa contains vitamin K. Alfalfa should not be used with prednisone.
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