Red clover: Evidence, Trial Doses & Interactions

About Red clover

A flowering-top extract standardised to isoflavones — genistein, daidzein, biochanin A and formononetin — used for menopausal symptoms. It is the main non-soy source of supplemental isoflavones.

Red clover isoflavone trials for hot flushes are numerous, small and mostly manufacturer-supported, with pooled results that hover around the boundary of statistical significance and vary depending on which trials are included. Because isoflavones bind oestrogen receptors, its safety in hormone-sensitive cancer is an open question rather than a resolved one, and long-term endometrial safety data are limited.

Sold as

Standardised isoflavone tablet, Capsule, Tea, Tincture

Standardised to

Trials used extracts providing 40–80 mg total isoflavones daily — a product without this marker may not resemble what was studied.

Also known as

Trifolium, Promensil, Cow clover

What the research used

The amounts, forms and durations published trials of Red clover actually administered.

These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.

Studied for Menopausal hot flushes
40–80 mg
Limited
Standardised isoflavones, daily · 12 weeks to 12 months
Most trials used one of two branded isoflavone products and were supported by their manufacturers. Pooled effects are small and unstable across analyses.

This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.

When it was taken

Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.

None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.

With food
Not enough
Taken with food by convention. Isoflavone absorption depends heavily on gut bacteria — only some people convert daidzein to equol — which matters more than time of day and is not something a label can control for.
Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.

What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.

Menopausal symptoms

Women's Health

Limited evidence

Some trials report a modest reduction in daily hot flush frequency, and pooled estimates sit close to the threshold of significance with substantial heterogeneity. Manufacturer funding is common across this literature.

What may be going on: Isoflavones bind oestrogen receptors, with greater affinity for the beta receptor, producing weak oestrogenic and antioestrogenic effects depending on context.

Limited evidence. Early human work, or mostly lab and animal research.

View the 4 sources

Soy Isoflavones and Breast Cancer Risk: A Meta-analysis.(opens in a new tab)
Meta-analysis · In vivo (Athens, Greece) · 2022 · PMID 35241506
Isoflavone Supplements for Menopausal Women: A Systematic Review.(opens in a new tab)
Systematic review · Nutrients · 2019 · PMID 31689947
Evaluation of Clinical Meaningfulness of Red Clover (Trifolium pratense L.) Extract to Relieve Hot Flushes and Menopausal Symptoms in Peri- and Post-Menopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.(opens in a new tab)
Meta-analysis · Nutrients · 2021 · PMID 33920485
Efficacy of phytoestrogens for menopausal symptoms: a meta-analysis and systematic review.(opens in a new tab)
Meta-analysis · Climacteric : the journal of the International Menopause Society · 2015 · PMID 25263312

Deep research mode adds each paper’s own conclusion and stated limitations.

Blood lipid profile

Heart Health

Not enough evidence

There is not enough consistent human research on red clover and blood lipids; trials report small and inconsistent changes.

Not enough evidence. Not enough human research to say anything useful yet.

View the 4 sources

Isoflavones obtained from red clover improve both dyslipidemia and menopausal symptoms in menopausal women: a prospective randomized placebo-controlled trial.(opens in a new tab)
Randomised controlled trial · Climacteric : the journal of the International Menopause Society · 2024 · PMID 39254422
Effects of red clover on perimenopausal and postmenopausal women's blood lipid profile: A meta-analysis.(opens in a new tab)
Meta-analysis · Climacteric : the journal of the International Menopause Society · 2018 · PMID 30269660
Influence of red clover-derived isoflavones on serum lipid profile in postmenopausal women.(opens in a new tab)
Randomised controlled trial · The journal of obstetrics and gynaecology research · 2009 · PMID 20144173
A biochanin-enriched isoflavone from red clover lowers LDL cholesterol in men.(opens in a new tab)
Randomised controlled trial · European journal of clinical nutrition · 2004 · PMID 14985677

Deep research mode adds each paper’s own conclusion and stated limitations.

Bone mineral density

Bone Health

Not enough evidence

Evidence is limited for red clover and bone density. A small number of trials report changes in bone turnover markers with no dependable effect on fracture-relevant outcomes.

Not enough evidence. Not enough human research to say anything useful yet.

View the 1 source

The effect of isoflavones extracted from red clover (Rimostil) on lipid and bone metabolism.(opens in a new tab)
Randomised controlled trial · Menopause (New York, N.Y.) · 2001 · PMID 11449083

Deep research mode adds each paper’s own conclusion and stated limitations.

Things to know

Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.

Worth knowing
Hormone-sensitive cancers
Isoflavones are oestrogen receptor ligands, and their safety in breast, ovarian and endometrial cancer, or alongside tamoxifen and aromatase inhibitors, is not established. This needs oncology input rather than a label warning.
Interaction
Anticoagulants and coumarin content
Interacts withWarfarin, antiplatelet drugs
Red clover contains coumarin derivatives and has been reported to affect bleeding. It should not be combined casually with warfarin or antiplatelet drugs, and should be stopped before surgery.
Avoid
Pregnancy and breastfeeding
Oestrogenic activity makes red clover inappropriate in pregnancy and breastfeeding.
Interaction
Hormonal therapies and drug metabolism
Interacts withOral contraceptives, hormone therapy, CYP3A4 substrates
It may interact with oral contraceptives and hormone therapy, and laboratory work suggests effects on CYP enzymes including CYP3A4.
Worth knowing
Endometrial safety over the long term
Trials have mostly run a year or less, which is not long enough to characterise endometrial effects of sustained isoflavone exposure.

Red clover

What red clover may help with

About Red clover

What the research used

When it was taken

With food

The evidence in depth

Menopausal symptoms

Blood lipid profile

Bone mineral density

Things to know

Hormone-sensitive cancers

Anticoagulants and coumarin content

Pregnancy and breastfeeding

Hormonal therapies and drug metabolism

Endometrial safety over the long term

What red clover may help with

About Red clover

What the research used

When it was taken

🍽️With food

The evidence in depth

Menopausal symptoms

Blood lipid profile

Bone mineral density

Things to know

Hormone-sensitive cancers

Anticoagulants and coumarin content

Pregnancy and breastfeeding

Hormonal therapies and drug metabolism

Endometrial safety over the long term

With food