Category: Herbs & Ingredients
Spearmint tea lowered testosterone markers in two small trials, which is why it circulates as a natural anti-androgen. The blood chemistry moved; measured hair growth did not clearly follow in a month. Here is the honest grade.
Category: Ingredient Intelligence | Reading time: ~13 min | Level: Intermediate
A kitchen herb rarely earns a place in the hormone conversation, and spearmint got there on the strength of a single, tidy observation repeated in two small studies: when women drank its tea twice a day, their testosterone markers went down. That is an unusual thing for a plant most people associate with chewing gum and lamb sauce to do, and it is why spearmint now circulates online as a natural anti-androgen. The finding is real. It is also far narrower than the reputation built on top of it.
The honest story of spearmint is the story of a gap. On one side sits the blood chemistry, where the trials genuinely moved the needle within days to weeks. On the other sits the thing people actually want, a visible change in skin or hair, which the same trials did not clearly deliver in the time they ran. Understanding why those two things came apart, and why that is exactly what you would expect from biology rather than a failure of the herb, is the difference between using spearmint with clear eyes and expecting it to do something it has never been shown to do.
Here is the short version before the detail. Two small randomised trials found spearmint tea, taken twice daily, was associated with lower free and total testosterone and higher LH and FSH in women. In the longer of the two, self-reported hair improved but the objective clinical hirsutism score did not change significantly over 30 days. Spearmint is a safe, food-grade herb, but its evidence is a limited, emerging signal about hormone markers, not proof that it treats a condition. Treat the marker change as interesting and the promised outcome as unproven, and you will read spearmint correctly.
Spearmint is Mentha spicata, a hardy perennial mint grown worldwide as a culinary and tea herb, and it is a genuinely different plant from peppermint (Mentha x piperita), which is a hybrid. The two share a family and a cooling character, but their chemistry differs, and it is spearmint specifically, not mint in general, that the hormone research studied. As a food it has an unbroken record of ordinary use in cooking, sweets and tea across many cultures.
Its research interest rests on a single mechanistic idea drawn from human trials: something in spearmint tea appears to lower circulating androgen activity, which is why the studies measured a drop in testosterone alongside a rise in the pituitary hormones LH and FSH. [1] The precise compounds and the exact pathway are not firmly established from those small studies, so the fair way to describe the mechanism is as an observed hormone-marker shift rather than a mapped biochemical route. A cup of spearmint tea, in other words, is being asked to do something a culinary herb is not obviously built to do, and the evidence that it does is early.
Almost everything specific that can be said about spearmint and hormones comes from two studies, and it is worth walking through both rather than citing them as a vague consensus.
The most cited is a 2010 randomised controlled trial published in Phytotherapy Research, in which 42 women with polycystic ovary syndrome drank spearmint tea twice daily for 30 days. [1] Over that month the spearmint group showed reduced free and total testosterone and increased LH and FSH compared with the control condition. [1] That combination, lower androgens with higher gonadotropins, is a coherent endocrine picture rather than a random wobble, which is part of why the study drew attention. Crucially, the trial also asked about hair. Patient-reported hirsutism improved, but the objective clinical measure, the Ferriman-Gallwey score, did not change significantly over the 30 days. [1] The blood markers moved; the measured hair did not.
The earlier study, published in 2007 in the same journal, was smaller and shorter still: 21 women with hirsutism drank spearmint tea twice daily for 5 days, and the researchers reported decreased free and total testosterone. [2] Five days is far too short to expect any physical change and the study did not claim one; its value is simply that it pointed in the same direction as the later trial. Two small studies agreeing on the direction of a hormonal effect is more persuasive than either alone, but it is still two small studies.
What the mechanism looks like beyond these human trials leans on animal and laboratory work, which is why the anti-androgen idea should be framed honestly as a hormone-modulation signal rather than a proven clinical action. Neither trial was large, neither ran long, and neither demonstrated that spearmint changes an outcome a person can see or feel. The consistency is real; the strength of evidence is limited.
It is worth being candid about how little the two trials actually tell us about the mechanism, because that honesty is part of the grade. Spearmint leaf is rich in polyphenols, including rosmarinic acid and a range of flavonoids, and it is one of these constituents, or some combination of them, that is presumed to sit behind the hormonal signal. The trials measured what happened to circulating hormones; they did not isolate a compound, map a receptor, or trace a pathway, so any confident biochemical account of how spearmint lowers androgens is running ahead of the human evidence. [1][2]
The pattern the studies described does at least hang together internally. Testosterone markers fell while LH and FSH rose, and those two moving in opposite directions is consistent with a genuine shift in the endocrine feedback loop rather than a measurement artefact. [1] What the studies cannot say is where in that loop spearmint acts, whether the effect is on production, on conversion, or on how the hormones are carried and cleared. Supporting ideas about the mechanism lean on animal and laboratory work rather than on these two small human trials, which is precisely why the responsible framing is a hormone-modulation signal rather than a proven mode of action. When you read a confident claim that spearmint blocks a specific enzyme or receptor in humans, that claim is extrapolating well beyond what two short tea studies established.
The single most important thing to understand about spearmint is why the 30-day trial could show a genuine drop in testosterone markers and, at the same time, no significant change in the objective hirsutism score. This is not a contradiction. It is biology working on two different clocks.
Hormone levels in blood can shift quickly, within days, because they reflect ongoing production and clearance. A hair follicle does not work like that. Terminal hairs grow, rest and shed over a cycle measured in months, so even if you switched off an androgen signal completely, the hairs already in place would take a long time to respond, and the follicle's behaviour would only change over successive cycles. A 30-day window is arguably too short to reveal a real hair effect even when the upstream hormone change is genuine. [1] The self-reported improvement the women described is easy to over-read: subjective ratings over a month, in people who know they are drinking a herbal tea for this reason, are exactly the kind of measure that can move on expectation alone.
So the responsible reading is layered. The marker change is the strongest part of the spearmint story and it is plausibly real. Any downstream benefit is unproven, partly because the studies were short and partly because the biology of hair would not show its hand that fast. Anyone selling spearmint as a way to clear unwanted hair is promising the part the evidence does not support while borrowing credibility from the part it does.
If you want to try spearmint tea, the practical guidance is simple, because the trials themselves were simple. Both used spearmint tea twice daily, morning and evening, prepared in the ordinary way from dried spearmint leaf. [1][2] There is no evidence base for capsules, concentrated extracts or a specific milligram dose, and no long-term trial to lean on, so a twice-daily cup is the only regimen with any research behind it, and even that rests on 5-day and 30-day studies.
Set expectations to match the evidence. The realistic, evidence-based hope is a modest shift in androgen markers over weeks, the kind of thing you would only ever see on a blood test, not in the mirror. The unproven hope is any visible change, and if that is your reason for drinking it, the honest answer is that spearmint has not been shown to deliver it. Give any trial of it enough time, and judge it by what it was actually shown to affect rather than by what you were hoping for.
There are a few things worth raising with a prescriber rather than deciding alone. If you have a diagnosed hormonal condition, spearmint is a hormone-active ingredient and belongs in that conversation. If you are on any medication that touches hormones, or anything where an androgen shift could matter, mention it. And if you take spearmint seriously enough to drink it deliberately twice a day for its hormonal effect, then it deserves to be treated as an active ingredient, not just a nice tea, which means the same care you would give any supplement that changes your chemistry.
Spearmint's culinary safety record is reassuring, and both trials reported it was well tolerated at the amounts used. [1][2] The caution attached to it is not about toxicity; it is about the very effect that makes it interesting. A herb that can nudge androgen levels is, by definition, doing something hormonal, and that means a few groups should not treat it as a neutral beverage.
Pregnancy and breastfeeding are the clearest cases: hormone-active herbs have not been studied for safety in these settings, and the sensible default is to avoid deliberate therapeutic use. Anyone with a hormone-sensitive condition, or anyone taking hormone-related medication, should treat spearmint as something that could add to or interfere with what their body or their prescription is already doing, and clear it first. Men who drink the occasional cup have little to be concerned about, since the human evidence is in women and normal culinary amounts are small, but anyone deliberately consuming large daily quantities and worried about androgens should raise it with a clinician.
Pregnant, breastfeeding, or on medication? Check with a healthcare professional first.
Spearmint is a good test of whether a guide is being straight with you. It is easy to write it up as a natural anti-androgen and stop there, because that framing sells. The more useful version tells you exactly where the evidence stops: two small trials moved a blood marker, one of them found no objective change in the outcome people care about, and nothing has been shown over the long term. That is not a reason to dismiss spearmint. It is the reason to hold it lightly, as a promising early signal rather than a solution.
If you want to see how spearmint sits alongside other hormone-adjacent herbs, each graded by the same honest standard rather than by marketing enthusiasm, the Remedy Library lays them out so you can compare what is actually known. The aim is to match what you try to what the research can support, and to keep the parts that are still unproven clearly labelled as such.
Spearmint earned its hormonal reputation from two small studies that agreed on a clean finding: its tea, taken twice daily, was associated with lower testosterone markers and higher LH and FSH in women. That signal is genuine and worth knowing. What has not been shown is that the shift produces any visible result, because the one trial that looked found no significant change in the objective hirsutism score over a month, which is roughly what the slow biology of hair would predict. Drink spearmint if you like it, and if you are curious about its mild endocrine signal, but hold the outcome loosely. The evidence here is limited and emerging, and the honest grade is the whole point.
1. Grant P, et al. Spearmint herbal tea has significant anti-androgen effects in polycystic ovarian syndrome: a randomised controlled trial. Phytotherapy Research, 2010. RCT, 42 women, 30 days. 2. Akdoğan M, et al. Effect of spearmint (Mentha spicata Labiatae) teas on androgen levels in women with hirsutism. Phytotherapy Research, 2007. Clinical trial, 21 women, 5 days.
In two small trials it lowered androgen markers in women. The most cited study had 42 women with polycystic ovary syndrome drink spearmint tea twice daily for 30 days, and it measured reductions in free and total testosterone with a rise in LH and FSH. An earlier five-day trial in 21 women reported the same direction of change. Both are small and short, so the finding is best read as a consistent early signal rather than a settled fact.
Both trials used spearmint tea taken twice a day. The commonly cited preparation is roughly one cup made from about a teaspoon of dried spearmint leaf, steeped and drunk morning and evening. The studies ran for 5 days and 30 days respectively, so there is no evidence base for a specific long-term dose.
This is where honesty matters. In the 30-day trial the women reported feeling their hair had improved, but the objective clinical hirsutism score did not change significantly over that month. Hair follicles turn over on a timescale of months, so a month is arguably too short to see a real change even if the hormonal shift is genuine. The blood chemistry moved faster than any visible effect could.
No. Spearmint is Mentha spicata and peppermint is Mentha x piperita, a hybrid. They share a family and a menthol-adjacent character, but they are different plants with different chemistry. The androgen research was done on spearmint specifically, so peppermint findings should not be assumed to carry over.
As a culinary herb, spearmint has a long record of safe use in food and drink, and the trials reported it was well tolerated. The caveat is that its point of interest is a hormonal effect, so anyone with a hormone-sensitive condition, anyone pregnant or breastfeeding, or anyone on hormone-related medication should treat it as an active ingredient and check with a professional first.
The androgen markers moved within days to weeks in the trials, with measurable change by the 5-day and 30-day marks. Any downstream effect a person might hope for, such as a change in skin or hair, would be far slower and was not demonstrated in the short studies.
Not necessarily nothing, but not proven to do the thing people want either. The reduction in testosterone markers was real in the study; the absence of an objective hirsutism change over 30 days most likely reflects how slowly hair follicles respond, not that the hormone shift was fake. The honest position is that the upstream signal is there and the downstream benefit is unproven on this timescale.
No. The evidence for spearmint is two small, short trials measuring blood markers, which is a different order of proof from a licensed medication with dosing and outcome data. Spearmint may nudge androgen markers, but it has not been shown to treat any condition, and it is not a substitute for a treatment your prescriber has chosen. Never stop a prescribed medicine to try a tea.
The human trials were in women, and the amounts in normal culinary use are small, so an occasional cup is not a realistic concern. The research does not establish a meaningful testosterone-lowering effect in men at food amounts. If you are deliberately drinking large quantities daily and are concerned about androgens, that is a reasonable thing to raise with a clinician, but everyday use sits well within the range people have drunk for centuries.
Because the direction of the finding was clean and it matched an older observation, and because a safe kitchen herb showing any hormonal signal is genuinely interesting. Attention is not the same as strong evidence, though. The right way to hold it is: promising enough to study further, not proven enough to promise a result.