Spearmint Tea and PCOS: Does It Lower Testosterone?

The clinical evidence

There are two key studies examining spearmint tea for androgen reduction in women:

Akdogan et al. (2007) — the pilot study

This Turkish study enrolled 21 women with hirsutism and gave them two cups of spearmint tea per day for five days. The results showed a statistically significant reduction in free testosterone, with no change in total testosterone. The researchers also noted a reduction in LH. While only a pilot study — short duration, small sample — it established the plausibility of spearmint's anti-androgenic effect in humans and prompted the more rigorous follow-up.

Grant (2010) — the randomised controlled trial

This is the most cited spearmint study in PCOS. Grant conducted a 30-day double-blind, randomised controlled trial in 42 women with PCOS or idiopathic hirsutism. Participants were randomised to two cups of spearmint herbal tea or chamomile tea (the control) daily. The results:

• Free testosterone fell significantly in the spearmint group relative to chamomile
• LH increased significantly — indicating improved gonadotropin signalling toward the pituitary
• FSH increased significantly — consistent with better follicular stimulation
• Total testosterone was not significantly changed, suggesting the primary effect was on free (biologically active) androgen levels
• Self-reported hirsutism scores also improved in the spearmint group, though this subjective measure requires longer follow-up to be definitive

The study was published in Phytotherapy Research and has been repeatedly cited as the strongest existing evidence for spearmint's anti-androgenic effects in PCOS.

How spearmint lowers testosterone

Spearmint (Mentha spicata) contains several bioactive compounds, but the primary candidates for its anti-androgenic activity are rosmarinic acid, carvone, and a range of flavonoids.

5-alpha-reductase inhibition

5-alpha-reductase is the enzyme that converts testosterone into dihydrotestosterone (DHT) — the more potent androgen responsible for hirsutism (body and facial hair growth), androgenic alopecia (scalp hair thinning), and acne. Rosmarinic acid and several flavonoids in spearmint have demonstrated inhibitory activity against 5-alpha-reductase in laboratory studies. By reducing the conversion of testosterone to DHT, spearmint can reduce androgenic signalling at the tissue level even without dramatically lowering circulating total testosterone.

Androgen receptor antagonism

Some compounds in spearmint have demonstrated weak androgen receptor binding activity in cell studies — meaning they can compete with testosterone and DHT for receptor binding sites. This is a partial antagonist mechanism similar in principle (though very different in magnitude) to pharmaceutical antiandrogens like spironolactone. The clinical relevance of this mechanism from tea drinking is uncertain, but it may contribute to the reduction in free testosterone activity observed in the Grant trial.

LH and FSH effects

The increases in LH and FSH seen in the Grant trial suggest that spearmint may also act upstream in the hypothalamic-pituitary axis. Reduced androgen feedback to the pituitary can allow LH and FSH to rise — the same mechanism by which anti-androgenic medications often normalise gonadotropin ratios in PCOS. This is biologically consistent with the observed hormonal changes.

The dose and preparation

The evidence-backed protocol from the Grant (2010) trial is straightforward:

• Two cups per day — one in the morning, one in the evening
• One heaped teaspoon of dried spearmint leaves per cup (Mentha spicata)
• Steep in boiling water for 5 minutes, covered (covering retains volatile compounds)
• Drink while warm — no milk, as tannin binding is not a concern here but milk has not been studied in this context

Spearmint tea bags are a convenient alternative to loose leaf — most standard spearmint tea bags contain roughly one teaspoon equivalent of dried herb. The key is ensuring the product is Mentha spicata (spearmint) rather than Mentha piperita (peppermint) — they are different plants with meaningfully different active compound profiles.

Spearmint vs peppermint — why it matters

Spearmint and peppermint are different plants that are frequently confused. Mentha spicata (spearmint) contains carvone as its primary volatile compound, along with rosmarinic acid and specific flavonoids associated with the anti-androgenic effects. Mentha piperita (peppermint) is a hybrid of spearmint and watermint, with a significantly higher menthol content and a distinct phytochemical profile.

The clinical studies used spearmint exclusively. Peppermint has not been tested for anti-androgenic effects in PCOS and should not be assumed to be equivalent. If you have been drinking peppermint tea thinking it is equivalent to the studied intervention, switch to spearmint.

Spearmint for hirsutism

Hirsutism — unwanted dark, coarse hair growth on the face, chest, abdomen, and back — is one of the most distressing symptoms of androgen excess in PCOS. It is caused by DHT stimulating androgen-sensitive hair follicles to produce terminal (thick, pigmented) hair in areas typically only active in men.

Spearmint tea's anti-androgenic mechanism — particularly its 5-alpha-reductase inhibition — targets the correct pathway for hirsutism management. However, a critical point for realistic expectations: existing terminal hair follicles do not immediately revert when androgen levels fall. They require months of reduced DHT stimulation before miniaturising back toward finer hair. The Grant (2010) study was only 30 days, which is far too short to observe meaningful visible hair reduction — participants reported improved subjective hirsutism scores, but this likely reflects slowing of new growth rather than reversal of existing hair.

Visible hirsutism improvement from any anti-androgenic intervention — including prescription spironolactone — typically takes 3–6 months of consistent use. Spearmint tea, at two cups per day, should be viewed as a gentle, accessible long-term intervention in this context rather than a fast-acting solution.

Spearmint for PCOS-related hair loss

Androgenic alopecia (scalp hair loss driven by DHT) in PCOS operates through the same DHT mechanism as hirsutism, but in the reverse direction — DHT miniaturises scalp follicles rather than stimulating body follicles. Spearmint's 5-alpha-reductase inhibition is therefore mechanistically relevant to scalp hair loss as well.

No clinical trials have specifically examined spearmint tea for PCOS-related androgenic alopecia. The evidence is mechanistic and indirect. Women using spearmint tea as part of a broader androgen-management strategy — alongside dietary changes, inositol, and adequate iron and ferritin levels — may see slowed progression of scalp hair thinning over months of consistent use. It is unlikely to regrow already-lost hair; its primary value is reduction of DHT-mediated follicle damage going forward.

Who benefits most

Spearmint tea's anti-androgenic mechanism is most relevant for women with PCOS who have elevated androgen markers — elevated free testosterone, DHEAS, or clear clinical signs of androgen excess (hirsutism, hormonal acne, androgenic alopecia). The Grant study enrolled women with confirmed PCOS or idiopathic hirsutism, and the effect size was most meaningful in those with elevated free testosterone at baseline.

Women with PCOS who have normal androgen levels (some lean PCOS phenotypes are driven by ovarian morphology and menstrual irregularity without significant androgen elevation) may see less benefit from a specifically anti-androgenic intervention like spearmint tea. In that context, the tea is still harmless and pleasant, but the physiological target may be less active.

Limitations of the evidence

The honest limitations of the spearmint evidence are worth stating clearly:

• Small sample sizes: Both key studies had fewer than 45 participants. Effect sizes should be interpreted with caution until replicated in larger trials.
• Short duration: 30 days is not enough time to assess most clinically meaningful PCOS outcomes (hirsutism reversal, menstrual cycle changes, fertility).
• No long-term safety data: Two cups of herbal tea per day is unlikely to pose risks, but no study has examined effects beyond 30 days.
• No standardisation: Spearmint tea products vary in rosmarinic acid and carvone content. The "dose" from different brands may not be equivalent to what was used in trials.
• No PCOS-specific fertility data: The mechanism is plausible, but spearmint tea has not been tested as a fertility intervention in PCOS.

Combining spearmint with other PCOS interventions

Spearmint tea is best understood as a low-risk, evidence-supported addition to a broader PCOS management approach — not as a standalone treatment. Its anti-androgenic mechanism complements rather than duplicates:

• Myo-inositol — works on insulin signalling and reduces androgen from the ovary via a different pathway; the two are complementary
• Low-GI, high-protein diet — reduces hyperinsulinaemia, which is one of the main drivers of ovarian androgen overproduction; spearmint does not address this directly
• Exercise — improves insulin sensitivity and SHBG; again complementary, not overlapping
• Magnesium and zinc — support insulin sensitivity and have some anti-androgenic properties; can be stacked with spearmint

Women using prescription anti-androgens (spironolactone, cyproterone acetate) should discuss adding spearmint tea with their prescribing doctor — not because of known interactions, but because stacking multiple anti-androgenic interventions can produce additive effects on androgen levels that may need monitoring.