Spearmint tea and PCOS hirsutism: a 30-day randomized controlled trial of 42 women shows lower testosterone but no visible hair change yet

The numbers that matter

Can we actually trust this?

This one's a proper randomized controlled trial. Women were randomly assigned to drink either spearmint tea or chamomile tea (which has no known effect on hormones) twice daily, and the researchers were blinded to who got which tea. That's a solid design.

The limitations are honest ones: the sample is small (42 women), the duration is short (30 days), and the primary clinical outcome (visible reduction in hair growth) wasn't achieved. But the researchers are transparent about why. Hair has its own growth cycle, and even pharmaceutical options like spironolactone take months before you see results in the mirror. A 30-day study was never going to show hair changes. What it did show is that the hormonal machinery is responding, and that's a meaningful starting point.

Does this apply to you?

This study is most relevant if:

• You have PCOS with hirsutism (excess hair growth) as a significant symptom.
• You're interested in natural, non-pharmaceutical options to complement your existing care.
• You're willing to be patient: the hormonal changes are real, but visible results take longer than 30 days.
• You're roughly 19–42 years old (the range in this study).
• As with any supplement, talk to your doctor before starting, especially if you're on other medications for PCOS.

Why this matters

If you've spent any time in PCOS communities online, you've probably seen someone mention spearmint tea. It's one of the most talked-about natural remedies for hirsutism. But does it actually work?

This study gives us a partial answer, and it's worth understanding what that means. The hormonal side is clear: spearmint tea significantly lowered both free testosterone (from 5.12 to 3.64 pg/mL) and total testosterone (from 0.81 to 0.62 ng/mL) over 30 days, while the chamomile group stayed basically flat. LH and FSH both went up, which is consistent with reduced androgen suppression. These aren't placebo-driven changes. The women drinking chamomile saw none of them.

But here's where it gets nuanced. The women in the spearmint group felt better about their hirsutism (their self-reported quality of life scores dropped from 17 to 11, a significant improvement). Yet when clinicians measured their hair growth objectively, the Ferriman-Gallwey scores barely moved (17 to 16, not significant).

Is that a failure? Not really. Hair follicles have their own timeline. Even spironolactone, the standard pharmaceutical option for hirsutism, takes three to six months before you start seeing visible changes. Expecting a tea to do in 30 days what medication can't is unrealistic. What the study shows is that spearmint is pulling the right hormonal levers. Whether that translates to less hair over time needs a longer study, and the researchers said exactly that.

If you want to try this

1. The dose in the study was simple.

   Two cups of spearmint tea per day, made from standardized herbal tea bags. Nothing fancy, nothing expensive. You can find spearmint tea bags at most grocery stores or online. Make sure it's pure spearmint (Mentha spicata), not peppermint, which is a different plant with different properties.

2. Think of this as a complement, not a replacement.

   If you're already on medication for PCOS (metformin, spironolactone, oral contraceptives), spearmint tea isn't a substitute. It's something you can add to your routine alongside your existing care. Talk to your doctor about it, especially if you're on spironolactone, since both have antiandrogen effects and you'll want to make sure they're not compounding in a way you don't expect.

3. Give it longer than 30 days.

   The study itself says this. If you start drinking spearmint tea hoping to see less facial hair by next month, you'll be disappointed. The hormonal changes may begin quickly, but hair growth cycles mean visible results take months. Commit to at least 3 months before you judge it.

4. Track everything.

   If you're going to try this, track it. Log your daily tea intake, take photos of the areas where you experience hirsutism (same angle, same lighting), and note how you're feeling. Without tracking, you'll never know whether it's working for you specifically.

A few terms, explained

Antiandrogen

Anything that reduces the effect of androgens (male hormones like testosterone) in your body. Some antiandrogens block androgens from reaching tissues; others lower the amount circulating in your blood. Spearmint appears to do the latter.

Ferriman-Gallwey score

A clinical scoring system that rates hair growth in nine body areas on a 0–4 scale. It's the standard way researchers objectively measure hirsutism so they can compare results across studies. In this trial, the spearmint group's scores went from 17 to 16, which wasn't a statistically significant change.

Free testosterone vs. total testosterone

Total testosterone is the full amount in your blood. But not all of it is active; much of it is bound to proteins and essentially neutralized. Free testosterone is the portion that's unbound and biologically active, the part actually driving symptoms like acne and excess hair growth. This study reduced both.

LH and FSH

Luteinizing hormone and follicle-stimulating hormone, two reproductive hormones produced by the pituitary gland. In PCOS, the ratio of LH to FSH is often elevated. In this study, both rose in the spearmint group, which is consistent with reduced androgen suppression and a shift toward a more balanced hormonal picture.

Study at a glance

Title

Spearmint herbal tea has significant anti-androgen effects in polycystic ovarian syndrome. A randomized controlled trial

Authors

Grant P

Journal

Phytotherapy Research, 2010

Volume

24; 186–188

DOI

10.1002/ptr.2900

Design

Two-centre, 30-day randomized controlled trial (researcher-blinded)

Setting

Two NHS district general hospitals, East Sussex, UK

Sample

n = 42 women with confirmed PCOS and hirsutism (41 completed), ages 19–42

Follow-up

30 days

Intervention

Spearmint herbal tea (standardized tea bags) twice daily for 30 days vs. chamomile tea (placebo) twice daily for 30 days