About Herbs

Bottom line: Alfalfa may be effective at reducing cholesterol levels. It is not effective against cancer.

Alfalfa contains fiber and compounds called saponins which are thought to bind with cholesterol in the body. In addition, alfalfa plants contain phytoestrogens which have been shown to act similarly to some human hormones. In fact, alfalfa phytoestrogens were more effective at inducing the growth of estrogen-dependent breast cancer cells than a form of estrogen commonly found within the body. Alfalfa seeds also contains a toxic amino acid L-canavanine. Levels of this amino acid vary widely and decrease as the plant matures. It is thought that this amino acid may be responsible for alfalfa's ability to cause a relapse of lupus symptoms in patients in remission from the disease. Researchers are unsure if large enough levels of the amino acid can be obtained from supplementation to have other detrimental effects in humans. Because alfalfa has estrogenic activity, patients with hormone sensitive cancers should use caution.

High Cholesterol:
Six subjects participated in a study of alfalfa and its cholesterol-lowering effects. Subjects were given 80 or 160 grams per day of ground alfalfa seeds for three weeks. Three of the subjects dropped out of the study. The remaining subjects showed reduction in plasma cholesterol levels after ingestion of alfalfa., However, it is difficult to draw a conclusion due to the small size of the sample, the large number of drop-outs and the lack of a control group.

Another clinical study involved fifteen patients with hyperlipoproteinemia, a disorder that results in high cholesterol and alfalfa. Patients were given 40 grams of alfalfa seeds three times a day for eight weeks. At the end of the study total cholesterol levels and low-density lipoprotein (LDL or "bad" cholesterol) levels had decreased significantly in patients with high LDL without affecting the high-density lipoprotein (HDL or "good" cholesterol) levels. The small size of the study and the absence of a control group limits the validity of the results.

Better, larger studies are necessary to understand the effects of alfalfa on high cholesterol.

Buffalo Herb, Lucerne, Purple Medick, Purple Medicle, Purple Medic

Alfalfa is a food crop, the leaves and seeds of which are widely used and thought to have diuretic properties and effective in treating diabetes, thyroid gland malfunction, arthritis, high cholesterol and peptic ulcers ⁽¹⁾ as well as promote menstruation and lactation ⁽²⁾. Alfalfa is also a popular treatment for asthma and hay fever ⁽²⁾. The herb is claimed to be a source of vitamins A, C, E and K and of the minerals calcium, potassium, phosphorus and iron ⁽³⁾. Small uncontrolled trials have shown that alfalfa can lower cholesterol levels in humans ^{(4) (5)}. Side effects are mainly gastrointestinal ⁽⁴⁾, however cases pancytopenia ⁽³⁾ and systemic lupus erythematosus relapse ⁽⁶⁾ have been reported. L-canavanine, a toxic amino acid contained in alfalfa seeds has been shown to affect T-cells ⁽⁷⁾, however researchers are unsure if dangerous concentrations of this substance can be obtained through supplementation ⁽⁸⁾.
Alfalfa sprout extracts exhibit potent estrogenic activity in vitro ⁽⁹⁾, therefore patients with estrogen sensitive cancers should use caution. Rats fed with alfalfa were more susceptible to colon cancer. Such effects have not been observed humans ⁽²⁾.
There are two reports of fatality due to ingestion of alfalfa from contaminated sources ⁽¹⁰⁾ and a fatal case of listeriosis following ingestion of contaminated alfalfa tablets ⁽²⁾.

Alfalfa seed and alfalfa sprout are available in many countries and used frequently as animal feed ⁽²⁾.

Foliage:
Carotinoids: lutein
Triterpene saponins: sojasapogenol A-E aglycones medicagenic acid, hederagenin
Isoflavonoids: formononetin glycosides, genistein, daidzein, biochanin A, coumestrol,
Coumarins: coumestrol, 3'-methoxy coumestrol, lucernol, sativol, trifol, medicagol
Triterpenes: sigmasterol, spinasterol
Cyanogenic glycosides

Seeds:
L-canavaine
Betaine: stachydrine, homostacydrine
Trigonelline
Fatty oil
^{(1) (3)}

Saponins present in the herb act on the cardiovascular, nervous and digestive systems ⁽¹⁾. The hypocholesterolemic and hemolytic activity of the leaves and sprouts of alfalfa are attributed to a steroidal saponin fraction. These saponins and fiber contained within the plant bind to cholesterol in vitro. Alkaloids such as stachydrine and l-homo-stachydrine found in the seed are thought to give alfalfa its emmenagogue and lactogenic activity ⁽²⁾. Extracts from alfalfa were preferentially agonistic towards estrogen receptor beta and alfalfa was shown to increase estrogen-dependent MCF-7 breast cancer cell proliferation even greater than estradiol ⁽⁹⁾. The non-protein amino acid constituent, L-canavanine constitutes 1.5% of the dry weight of alfalfa seeds and alfalfa sprouts. It has been shown to affect human T-cells in vitro and to induce hematologic and serologic abnormalities characteristic of systemic lupus erythematosus syndrome in monkeys ⁽¹²⁾. This mechanism has been proposed as the way in which systemic lupus erythematosus relapse occurs in humans as well ⁽⁷⁾, although some researchers question whether L-canavanine concentrations in alfalfa are great enough to cause this effect. ⁽⁸⁾.

Avoided during pregnancy and nursing ⁽¹¹⁾. Patients with latent systemic lupus erythematosus have had relapse after the ingestion of alfalfa tablets ⁽⁶⁾. Alfalfa sprouts have been linked to a number of E.coli and Salmonella infections in California ⁽¹⁰⁾.

Reported (Oral): Pancytopenia has been associated with ingestion of large amounts of ground alfalfa seeds ⁽³⁾. Increased fecal volume and defecation frequency, loose stools and diarrhea as well as abdominal discomfort and intestinal gas have all been reported in patients on alfalfa supplementation ⁽⁴⁾.

Alfalfa may increase serum urate and urea levels ⁽⁴⁾.

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.
Fifteen patients with hyperlipoproteinemia participated in a study of alfalfa seeds and cholesterol. Participants were given 40 grams of heat prepared alfalfa seeds three times daily for eight weeks. At eight weeks, total cholesterol levels and low density lipoprotein levels had decreased significantly without affecting HDL level. Side effects were minor gastrointestinal complaints. The small size of the study and the absence of a control group limit the validity of the results.

Malinow MR, McLaughlin P, Stafford C. Alfalfa seeds: effects on cholesterol metabolism. Experientia 1980;36:562-4.
Six subjects participated in a study of alfalfa and its cholesterol-lowering effects. Subjects were given 80 or 160 grams per day of ground alfalfa seeds for three weeks. Three of the subjects dropped out of the study. The remaining subjects showed reduction in plasma cholesterol levels after ingestion of alfalfa., However, it is difficult to draw a conclusion due to the small size of the sample, the large number of drop-outs and the lack of a control group.