alfalfa benefits: what the research does and doesn't show

The evidence doesn't support alfalfa, in leaf, seed or sprout form, as a treatment for high cholesterol, low fertility or low milk supply. Human testing is close to nonexistent: one three-week study in three people from 1980 and one 12-week trial in 60 men with a fertility diagnosis from 2024 make up almost the entire human record for this ingredient.

What the evidence doesn't support

It doesn't support alfalfa as a cholesterol-lowering supplement — the one human trial that exists had three participants. It doesn't support alfalfa as a galactogogue (a supplement to increase breast milk supply): a National Institutes of Health reference monograph states plainly that no scientifically valid clinical trials support that use, despite alfalfa appearing in some commercial milk-supply products. And despite alfalfa's isoflavone content being commonly discussed alongside menopause and hormone-related marketing, we found no human trial that tested alfalfa itself for that use — the isoflavone research that exists in this space is largely about other plants, not alfalfa.

What the trials found

A 1980 study gave three human volunteers a diet containing whole alfalfa seeds for three weeks. Plasma cholesterol concentrations fell during that period, and no signs of toxicity turned up on the serum tests the researchers ran. That's the entire human cholesterol record for alfalfa — three people, three weeks, no control group, and nothing published since that repeats or extends it in humans.

A separate line of research picks up the same idea in animals. A 2014 study fed an alfalfa saponin extract to 40 hyperlipidemic rats and measured the activity of several liver genes involved in cholesterol handling; the changes it found were consistent with the extract helping the liver clear more cholesterol. That's a plausible mechanism, but it's a rat study using an extract, not a human trial using a supplement you could buy, and animal cholesterol metabolism doesn't always translate to the same effect in people.

A 2024 randomized trial gave 60 men with a diagnosis of idiopathic infertility either 6 grams a day of alfalfa seed powder alongside vitamin E, or vitamin E alone, for 12 weeks. Sperm count, motility and the percentage of normally shaped sperm improved more in the alfalfa group than the vitamin-E-only group. Semen volume decreased in both groups, with no meaningful difference between them. Four pregnancies occurred in the alfalfa group during the study versus none in the comparison group — a number too small to draw a conclusion about pregnancy specifically. One participant in the alfalfa group withdrew due to abdominal bloating and one due to a respiratory allergic reaction. This is a single trial from one research group, in men with a specific fertility diagnosis, using seed powder rather than the dried leaf most alfalfa supplements are made from — it doesn't tell you anything about reproductive health in someone without that diagnosis.

On milk supply, the LactMed monograph is direct: daidzein and genistein (isoflavones present in alfalfa) are excreted into breast milk in small amounts generally, but that hasn't been measured specifically after alfalfa intake, and no data exist on alfalfa's other components in breast milk or on the safety or effectiveness of alfalfa in nursing mothers or infants at all.

Questions people ask

Is alfalfa good for cholesterol?

The entire human evidence base is one 1980 study with three participants over three weeks. A more recent rat study found a plausible mechanism using a concentrated extract, but that's animal research, not a human trial. Nothing here has been confirmed in a larger or more recent human study.

Does alfalfa help with menopause symptoms?

We found no human trial testing alfalfa specifically for menopause symptoms, despite its isoflavone content sometimes being discussed in that context. That's an absence of evidence, not a finding either way.

Can alfalfa help you get pregnant?

The one trial in this area studied men with a diagnosed fertility condition, using sperm quality — not pregnancy — as its primary measure. Four pregnancies occurred in a 30-person treatment group versus zero in a 30-person comparison group, which is too small a number to draw a conclusion from.

Does alfalfa increase milk supply?

The National Institutes of Health's own reference monograph on alfalfa says no scientifically valid clinical trial supports using it that way, despite its inclusion in some products marketed for that purpose.

Is alfalfa good for you?

It's recognized as safe to eat as a food. Whether it does anything specific for cholesterol, fertility or milk supply at typical supplement amounts isn't established by the small amount of human research that exists.

When to talk to a doctor

Alfalfa is not a treatment for high cholesterol, infertility or low milk supply, and nothing above should stand in for an evaluation by a doctor for any of those. If you're managing one of those as a diagnosed condition, that's a conversation for your doctor, not a decision to make from a supplement aisle.