Perimenopause Supplements: What the Evidence Says

If you are searching for a supplement to ease perimenopause symptoms, the honest summary is that the clinical evidence is weak and inconsistent for most of them. The Menopause Society's 2023 review of nonhormone treatments placed supplements and herbal remedies — including black cohosh, soy foods, soy extracts, and the soy metabolite equol — in its "not recommended" column, because the evidence ranged from limited to inconsistent. NICE in the UK takes a softer line, saying there is "some evidence" that isoflavones or black cohosh may relieve hot flashes and night sweats, but warns that the safety and purity of unregulated products is uncertain and that they can interact with medicines. One reason results look so mixed: in trials of menopause treatments, placebo alone improves symptoms in roughly 20% to 66% of women, so a supplement has to clear a high bar to prove it does anything real. None of this means a supplement can't help you personally — it means the population-level evidence is thin, the products are loosely regulated, and you should talk to your doctor before starting one, especially if you take other medications or have a hormone-sensitive condition.

Walk down any pharmacy aisle or open any wellness app and you will find supplements promising relief from hot flashes, night sweats, mood swings, and fatigue. Perimenopause is a long, disruptive transition, and the appeal of a natural-seeming pill is obvious. But "natural" is not the same as "effective" or "safe," and the gap between marketing and clinical evidence here is wide.

This article walks through what the major clinical bodies actually conclude about the most common perimenopause supplements, traced to primary sources: The Menopause Society, the UK's NICE, the U.S. National Center for Complementary and Integrative Health (NCCIH), and the American College of Obstetricians and Gynecologists (ACOG). The goal is not to tell you what to take — that is a conversation for you and your clinician — but to give you the evidence base so you can have that conversation on equal footing.

Why the evidence looks so messy: the 20% to 66% placebo problem

Before looking at any single supplement, it helps to understand why menopause-supplement studies are so hard to read. In its 2023 nonhormone therapy position statement, The Menopause Society notes that trials of nonhormone treatments for vasomotor symptoms — hot flashes and night sweats — have a placebo improvement rate of 20% to 66%, and that women with more anxiety tend to show an even higher placebo response.

That is a remarkable range. It means a large share of women improve on a sugar pill alone. So when a supplement trial reports that participants felt better, that result is only meaningful if the supplement clearly beat placebo — and for most products, it does not, or the trials disagree with each other. This is the backdrop for almost every finding below.

What The Menopause Society's 2023 review concluded

The Menopause Society (formerly the North American Menopause Society) published an updated, evidence-graded review of nonhormone treatments for menopausal hot flashes and night sweats in 2023. It rated each option on three levels: Level I for good and consistent evidence, Level II for limited or inconsistent evidence, and Level III for expert opinion.

The headline for supplements is blunt. In the "not recommended" category, the statement lists supplements and herbal remedies (Levels I-II), along with soy foods and soy extracts, and the soy metabolite equol. In other words, after reviewing the published literature, the panel did not find the evidence strong enough to recommend these products for hot flashes and night sweats.

What it did recommend instead were nonhormone options with stronger support: cognitive behavioral therapy, clinical hypnosis, certain antidepressants (SSRIs and SNRIs), gabapentin, and the newer drug fezolinetant, among others. The contrast is the point — these reached the bar that the supplements did not.

Source: The Menopause Society — 2023 Nonhormone Therapy Position Statement

Black cohosh: popular, but the evidence pulls in different directions

Black cohosh is one of the most purchased botanicals for menopause, and it is also a good example of how confusing this field is. NCCIH summarizes the split: a 2017 meta-analysis found black cohosh more effective than placebo at reducing hot flashes, while a 2016 review found no high-quality, consistent evidence that it beats placebo. Both can be cited honestly, which is exactly why a single clear recommendation is hard to make.

On safety, NCCIH notes black cohosh is generally well tolerated for up to about 12 months in trials, with mild side effects like stomach upset and headache, but there have been rare reports of liver damage where a causal link could not be confirmed. NICE includes black cohosh among the complementary options with "some evidence" of benefit for hot flashes, while cautioning that preparations vary, their safety is uncertain, and interactions with other medicines have been reported.

The practical takeaway: black cohosh is not a clear win, the products on shelves are not standardized, and anyone with liver concerns or on other medications should raise it with a clinician first.

Source: NCCIH — Menopausal Symptoms and Complementary Health Approaches

Soy isoflavones and red clover: modest at best

Soy isoflavones are plant compounds that act weakly on estrogen receptors, which is the theory behind their use for hot flashes. NCCIH cites a 2016 meta-analysis finding modest reductions in hot flash frequency and vaginal dryness, but no significant reduction in night sweats. Red clover, another isoflavone source, has shown some benefit for vaginal dryness and, in some trials, hot flash frequency — but, again, with inconsistent results across studies.

The Menopause Society's 2023 statement went further and placed soy foods, soy extracts, and the soy metabolite equol in the "not recommended" group. ACOG and other reviews echo the caution: clinical trial results are largely insufficient to firmly support or rule out a benefit, because some trials show a reduction and most show no difference from placebo.

On safety, NCCIH considers soy generally safe for short-term use and notes that eating soy foods appears safe for breast cancer survivors, though the safety of concentrated supplements is less certain, and long-term use has been linked to thickening of the uterine lining. If you have or have had a hormone-sensitive condition, isoflavone supplements are a specific thing to discuss with your doctor.

Source: NCCIH — Menopausal Symptoms and Complementary Health Approaches

Evening primrose oil, vitamin E, dong quai and DHEA: little to go on

For several popular supplements, the issue is not that they failed — it is that there is barely any good research to judge them by. NCCIH states that very little research has been done on evening primrose oil and dong quai for menopausal symptoms, so no conclusions can be drawn about whether they help.

Vitamin E has been studied a bit more, but the effect is small: NCCIH cites research where women taking vitamin E had on average about one fewer hot flash per day, and it flags that high-dose vitamin E may raise bleeding risk. DHEA is described as uncertain for menopause symptoms. None of these reach the level of a clear, evidence-backed recommendation, and "we don't know" is a legitimate and important answer.

Source: NCCIH — Menopausal Symptoms in Depth

St John's wort and the interaction trap

St John's wort is sometimes used for the low mood that can accompany perimenopause, and NICE notes some evidence it may relieve vasomotor symptoms. But NICE singles it out for a serious warning: uncertain dosing, variable potency between preparations, and the potential for serious interactions with other medicines, including tamoxifen, anticoagulants, and anticonvulsants.

This is a reminder that "herbal" does not mean inert. A supplement active enough to affect your mood is active enough to interfere with prescription drugs — which is exactly why your clinician needs to know everything you are taking, not just what they prescribed.

Source: NICE NG23 — Menopause: identification and management, Recommendations

What the regulators agree on

Across NICE, The Menopause Society, ACOG, and the NHS, a few consistent themes emerge even where specific verdicts differ.

First, the products themselves are loosely regulated. NICE warns that the quality, purity, and constituents of complementary preparations may be unknown, and that different products vary — so two bottles of "black cohosh" are not necessarily the same. Second, interactions are real, as the St John's wort example shows. Third, the official advice is the same everywhere: the NHS recommends talking to a doctor before taking herbal supplements or complementary medicines.

None of the major bodies says supplements are guaranteed useless, and some people do report relief. What they say is that the population-level evidence is weak or mixed for most products, the safety data is incomplete, and the decision belongs in a conversation with a healthcare professional who knows your full history.

How to think about it for yourself

Averages and trial results describe groups, not individuals. If you and your clinician decide a supplement is worth trying, the most useful thing you can do is treat it like a small experiment: note your symptoms before you start, change one thing at a time, and watch what actually happens over several weeks rather than going on a single good day.

That is hard to do from memory, because perimenopause symptoms fluctuate so much that it is easy to credit a supplement for a good stretch that would have come anyway. Consistent tracking is what separates a real effect from the 20% to 66% placebo improvement the data warns about — and it gives you and your doctor something concrete to look at instead of impressions.

About Rythma

Rythma is a perimenopause tracking app for iPhone that learns your personal symptom patterns and predicts difficult days before they arrive. Built specifically for the unpredictability of perimenopause — rather than the fixed 28-day cycle most period apps assume — it helps you anticipate symptoms, plan around hard days, and bring a clear symptom report to your doctor. If you are trying a new supplement or treatment, that record makes it far easier to see whether anything actually changed.

Download Rythma on the App Store →

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Rythma is a tracking and educational tool, not a medical device, and this article is for general information only — it is not medical advice. Perimenopause varies widely from person to person. Always consult a qualified healthcare professional about your symptoms, diagnosis, or treatment.