Menopause supplements: what has evidence and what does not

Reviewed by Emma Carter, Senior Health & Nutrition Editor

Walk into a pharmacy in perimenopause and the shelf will offer you black cohosh, red clover, soy isoflavones, evening primrose and a dozen blends. Some of it has been tested properly. Most of what has been tested did not work.

That sounds bleak, and it is not the whole story. Knowing which claims collapse under testing frees you to spend money and attention on the things that hold up. Here is what the trials found.

The short version

Supplement	Sold for	What the trials found
Black cohosh	Hot flashes, night sweats	No difference from placebo across 16 trials
Red clover extract	Hot flashes	No difference from placebo across the pooled trials
Soy isoflavones	Hot flashes, general symptoms	No conclusive evidence, with one possible exception below
Calcium and vitamin D	Bone protection	Meet calcium needs through food where possible; use vitamin D and calcium supplements according to national or clinical advice

Note what that table does not say. It does not say these products are dangerous, and it does not say nothing helps. It says the specific claim on the front of the box has been tested and mostly did not survive.

Black cohosh: the most studied, and the most disappointing

Black cohosh is the herb with the deepest trial record, which makes it the fairest test of the category.

A Cochrane review pooled 16 randomized trials covering 2,027 perimenopausal and postmenopausal women, most taking around 40 mg a day for an average of 23 weeks. Against placebo, black cohosh made no difference to how many hot flushes women had per day (mean difference 0.07 flushes, 95% CI −0.43 to 0.56) and no difference to overall menopausal symptom scores (standardised mean difference −0.10, 95% CI −0.32 to 0.11). Where trials compared it with hormone therapy, hormone therapy reduced flushes and symptom scores more (Cochrane, 2012).

Worth knowing that the guideline bodies do not read this identically. NICE says there is some evidence that isoflavones or black cohosh may relieve vasomotor symptoms, while warning that preparations vary, safety is uncertain and interactions with other medicines have been reported (NICE NG23).

Both can be true. A pooled analysis can find no average effect while individual products, at particular doses, remain untested rather than disproven. What you should not conclude is that the question is settled in the supplement's favor.

Soy and red clover

Phytoestrogens are plant compounds shaped a little like estrogen, which is the whole basis of the pitch. Cochrane pooled 43 randomized trials covering 4,364 women.

Red clover extract, the most commonly tested product, was no better than placebo for daily hot flush frequency (mean difference −0.93, 95% CI −1.95 to 0.10). The overall conclusion across all phytoestrogens was no conclusive evidence of benefit (Cochrane, 2013).

One finding cuts the other way and deserves stating. Four trials that could not be pooled with the rest found that extracts delivering more than 30 mg of genistein a day did consistently reduce hot flush frequency. That is a narrow, specific signal inside a broadly negative review, and it is not a licence to buy any soy product. If you want to test it, the dose of genistein is the number to look for, and most labels do not carry it.

On safety, the same review found no sign that these treatments stimulated the endometrium or vagina, or caused other adverse effects, when used for up to two years.

The number that explains the whole aisle

Here is the finding that makes sense of every glowing personal recommendation you have heard.

In the phytoestrogen trials, placebo alone reduced hot flush frequency by between 1% and 59%, depending on the trial (Cochrane, 2013).

Sit with that upper figure. A woman can take something inert, have her flushes drop by half, and recommend it to a friend in complete good faith. Menopause symptoms also fluctuate on their own and tend to ease with time, so anything you start during a bad patch gets credit for the improvement that was coming anyway.

This is not a reason to distrust your own experience. It is the reason trials use a placebo arm at all, and the reason "it worked for my sister" cannot settle the question.

What does carry evidence

• HRT is the main treatment for hot flashes and night sweats for many women. Our guide covers the benefits and risks for different health histories.
• Menopause-specific cognitive behavioral therapy. NICE recommends discussing CBT alongside HRT, or instead when HRT is not suitable or not wanted, for vasomotor symptoms, sleep problems and some depressive symptoms (NICE NG23).
• Food, exercise and individual bone-risk advice. The NHS recommends weight-bearing and resistance exercise, calcium-rich foods and vitamin D advice appropriate to your circumstances. It also states that menopause does not create separate calcium or vitamin D targets; calcium supplements may be prescribed when intake is low or osteoporosis is present (NHS). Our guides to calcium, vitamin D and bone health cover the details.
• Treating what is actually broken. If sleep is the problem, poor sleep has causes worth separating. Reaching for a menopause blend when the real issue is untreated insomnia wastes months.

Safety, which the label does not carry

Herbal does not mean inert. NICE flags that preparations vary between products, that their safety is uncertain, and that interactions with other medicines have been reported (NICE NG23). The NHS advises talking to a doctor before taking herbal supplements or complementary medicines (NHS).

Two situations where this stops being routine caution:

• You take other medication. Interaction is the risk, not toxicity.
• You have a personal history of breast cancer, or a high risk of it. Anything marketed for its estrogen-like activity is a conversation for your specialist, not the shop assistant.

What to actually do

Start by naming the symptom that bothers you most, then treat that rather than the life stage. Hot flashes, night sweats and broken sleep have different answers, and the strongest of those answers are not on the supplement shelf.

If you still want to try something herbal, do it as an experiment with an end date: one product at a time, a fixed period, and an honest look at whether anything changed. Given a placebo effect that can reach 59%, a single enthusiastic month proves very little. And tell your doctor what you are taking, because they cannot check for interactions with something they do not know about.

When to see a doctor

See your doctor if symptoms are disrupting your work, your sleep or your relationships, if you are considering HRT and want the risks explained for your own history, or before starting any herbal product alongside existing medication. Any bleeding after menopause needs checking, whatever supplement you are taking. Our guide to menopause covers what else changes and when to seek help.

Frequently asked questions

Does black cohosh work for hot flashes?

The largest review says no. Pooling 16 randomized trials in 2,027 women, black cohosh was no different from placebo in how many hot flushes women had each day, and no different in overall symptom scores. Hormone therapy beat it. NICE takes a softer line, saying there is some evidence it may relieve symptoms while warning that preparations vary and interactions have been reported.

Do soy isoflavones or red clover help menopause symptoms?

Across 43 trials in 4,364 women, red clover extract was no better than placebo for hot flush frequency. Four trials not included in the pooled analysis suggested that extracts with more than 30 mg of genistein a day did reduce flushes consistently, so the door is not fully closed. The overall verdict is no conclusive evidence.

Why do menopause supplements seem to work for so many women?

Because the placebo effect in this area is unusually large. In the Cochrane review of phytoestrogens, placebo alone reduced hot flush frequency by anywhere from 1% to 59% across trials. A supplement can be genuinely useless and still be followed by real improvement, which is exactly what a personal recommendation looks like from the inside.

Are menopause supplements safe?

Not automatically. NICE notes that many preparations are available, that their safety is uncertain, that different preparations vary, and that interactions with other medicines have been reported. The NHS advises talking to a doctor before taking herbal supplements or complementary medicines. This matters most if you take other medication or have a history of breast cancer.

What actually helps menopause symptoms if supplements do not?

HRT is the main treatment for hot flashes and night sweats for many women, and menopause-specific cognitive behavioral therapy can be used alongside it or when HRT is not suitable or wanted. For bones, focus on weight-bearing and resistance exercise, enough calcium from food, and vitamin D in line with national advice. Calcium tablets are not a routine menopause treatment and may be prescribed when intake is low or osteoporosis is present.

References

1. Black cohosh (Cimicifuga spp.) for menopausal symptoms · Leach MJ, Moore V, Cochrane Database of Systematic Reviews, 2012
2. Phytoestrogens for menopausal vasomotor symptoms · Lethaby A et al, Cochrane Database of Systematic Reviews, 2013
3. Menopause: identification and management (NICE guideline NG23) · NICE, updated 2026
4. Menopause and perimenopause: things you can do · NHS
5. Food for healthy bones · NHS