← The FormularyLong gameAlfalfa leaf
Also known as Medicago sativa. Lucerne.Twenty milligrams of lucerne. The safety file is the longer one.
Two things about alfalfa are true at once. The first is that the best-documented item in its file is a safety signal rather than a benefit: L-canavanine induced a lupus-like syndrome in monkeys fed alfalfa sprouts and reactivated that syndrome when fed on its own, and human case reports tie alfalfa tablets to lupus flares and to autoimmune haemolytic anaemia. The second is that canavanine is measured overwhelmingly in seed and sprout, at roughly 1.4 to 1.8 per cent of seed dry matter, and the published sources agree that levels fall as the plant matures. Here is the part we are not going to paper over: we looked for a published figure for canavanine in mature, milled alfalfa leaf and could not find one. So we cannot tell you how much canavanine is in 20 mg of it, and neither can anyone else selling it. That is exactly why the rule is not negotiable. If you have lupus or any autoimmune condition, do not take this, and do not let anyone's arithmetic talk you into it, because there is nothing on the benefit side of the ledger worth the trade. For everyone else, 20 mg of a forage legume is exactly what it sounds like.
The leaf of Medicago sativa, the deep-rooted forage legume grown for livestock and known in Britain as lucerne. Cut several times a season, dried and milled.
The proposed mechanisms belong to alfalfa's saponins, which bind cholesterol and bile acids in the gut and reduce how much is reabsorbed, and to its fibre. That is the cholesterol story, and it was produced with 120 grams a day of heat-treated seed, not with leaf powder. The leaf also carries phytoestrogens, chlorophyll, vitamin K and the canavanine that gives it its safety file. What any of it does at 20 mg has not been studied, and the honest mechanical answer is nothing measurable.
Traditionally used as a nutritive herb and a mild bitter. At 20 mg it is a completeness ingredient in a botanical blend rather than an active dose of anything.
Anyone who wants the traditional nutritive botanical in a blend and has no autoimmune history. Explicitly not for anyone with lupus, a lupus-like illness or any other autoimmune condition, anyone taking an immunosuppressant, anyone on warfarin or another vitamin K antagonist, anyone with gout, anyone with a hormone-sensitive cancer history, or anyone pregnant or breastfeeding.
20 mg daily with food as part of the LIVER blend. Nothing to time and nothing to separate it from, with one exception: if you are on warfarin, this and everything else carrying vitamin K is a conversation with your clinic before you start, not after.
Nothing. At 20 mg there is no effect to feel and none to measure. It is in the formula to complete the traditional botanical set, and we would rather say that plainly than dress it up.
Malinow and colleagues, in Science in 1982 (216:415-17), reported haematological and serological abnormalities resembling human systemic lupus erythematosus in cynomolgus macaques fed alfalfa sprouts, and reactivated the syndrome in previously affected animals by feeding L-canavanine sulphate alone. Human case reports followed: pancytopenia during ingestion of alfalfa seeds, Lancet 1981 (1:615), and 'Exacerbation of SLE associated with alfalfa ingestion', New England Journal of Medicine 1983 (308:1361). Alcocer-Varela and colleagues, Arthritis and Rheumatism 1985 (28:52-57), described dose-related effects of L-canavanine on human immunoregulatory cells in vitro, including abrogation of concanavalin-A-induced suppressor cell function, and noted that autoimmune haemolytic anaemia and SLE exacerbation had both been linked to alfalfa tablets. Published analyses put canavanine at roughly 1.4-1.8 per cent of alfalfa seed dry matter and 1.3-2.4 per cent in commercial sprouts, and state that levels decline with maturity; we found no published quantification for mature milled leaf. Memorial Sloan Kettering advises avoiding alfalfa in lupus and in gout. On the benefit side, the principal trial is Molgaard, von Schenck and Olsson, Atherosclerosis 1987 (65:173-79), an uncontrolled eight-week study in 15 patients with raised lipids given 40 g of heat-treated alfalfa seed three times daily; MSKCC summarises two such small trials and states plainly that larger controlled trials are necessary. Not supported: any claim that alfalfa treats, cleanses or protects the liver, and nothing here is a claim about cholesterol for this product.
Read the labelAlfalfa contains L-canavanine, linked in case reports to lupus flares and to autoimmune haemolytic anaemia. Do not take it if you have lupus, any autoimmune condition, or take an immunosuppressant — at any dose, including this one. It also carries vitamin K, which opposes warfarin: tell your anticoagulant clinic before taking anything containing it. Not a treatment for anything.
Evidence grades describe how well an ingredient is studied — A well-supported, C emerging — not a promise of results. Educational, not medical advice. Doses are typical ranges; follow the label on the product.