Alfalfa

Alfalfa () leaves and sprouts contain saponins, estrogenic isoflavonoids (e.g., daidzein, genistein), vitamin K, and the amino acid L-canavanine. Alfalfa is a purported galactogogue and is included in some proprietary mixtures promoted to increase milk supply;[1-5] however, no scientifically valid clinical trials support this use. Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.[6,7] Daidzein and genistein are excreted into breastmilk in small amounts,[8-11] but have not been measured specifically after alfalfa intake. No data exist on the excretion of other components of alfalfa into breastmilk or on the safety and efficacy of alfalfa in nursing mothers or infants. Alfalfa is generally well tolerated and is "generally recognized as safe" (GRAS) as a food by the U.S. Food and Drug Administration. Worsening of systemic lupus erythematosus has been reported, possibly caused by immune system stimulation by L-canavanine. Because of its vitamin K content, alfalfa should be avoided in persons taking warfarin. Dietary supplements do not require extensive pre-marketing approval from the U.S. Food and Drug Administration. Manufacturers are responsible to ensure the safety, but do not need to the safety and effectiveness of dietary supplements before they are marketed. Dietary supplements may contain multiple ingredients, and differences are often found between labeled and actual ingredients or their amounts. A manufacturer may contract with an independent organization to verify the quality of a product or its ingredients, but that does certify the safety or effectiveness of a product. Because of the above issues, clinical testing results on one product may not be applicable to other products. More detailed information about dietary supplements is available elsewhere on the LactMed Web site.