Ingredient Research and Sources
Last updated: October 2026
This page summarizes the published research on the herbs in our teas, so you can read the evidence yourself and judge how much weight it deserves. Every figure below comes from the linked source, and we describe each study’s size and limits as well as its findings.
Spearmint
Found in: Spearmint Tea (and discussed in our PCOS tea comparison)
What the research found
A small randomized trial (Grant, Phytotherapy Research, 2010) gave women with PCOS spearmint tea twice a day for 30 days, compared with a chamomile tea. Free and total testosterone fell significantly in the spearmint group. Patients’ own ratings of how hirsutism affected them improved, but the objective hair-growth scoring (Ferriman-Gallwey) did not change significantly over the 30 days.
An earlier, smaller study (Akdoğan et al., Phytotherapy Research, 2007) gave 21 women with hirsutism, 12 of whom had PCOS, spearmint tea twice a day for 5 days. Free testosterone fell, while total testosterone and DHEA-S did not change significantly.
The limits
Both studies were small and short, the longer one lasted only a month, and it found no significant change in clinician-measured hair growth. They do not show that spearmint treats PCOS.
Sources
Cinnamon
Found in: PCOS Glow Tea
What the research found
A placebo-controlled randomized trial (Kort and Lobo, American Journal of Obstetrics and Gynecology, 2014) gave 45 women with PCOS 1.5 g of cinnamon a day, or placebo, for 6 months. The authors described the result as preliminary evidence that cinnamon improved menstrual cyclicity.
The limits
One modest trial, using a measured daily supplement dose that is not the same as the cinnamon in a cup of tea. The authors themselves called the evidence preliminary.
Sources
Fenugreek
Found in: PCOS Glow Tea
What the research found
An open-label study (Swaroop et al., International Journal of Medical Sciences, 2015) followed 50 premenopausal women with PCOS who took a proprietary fenugreek seed extract for 90 days. The authors reported fewer ovarian cysts, a smaller ovarian volume and more regular menstrual cycles.
The limits
There was no control group and no randomization, so changes cannot be attributed to the extract alone. The product tested was a concentrated extract, not fenugreek brewed as a tea.
Sources
Ashwagandha
Found in: PCOS Glow Tea
What the research found
The US National Center for Complementary and Integrative Health (NCCIH) summarizes that some ashwagandha preparations may help with insomnia and stress, and that there is not enough evidence to say whether it helps other conditions, including female infertility.
On safety, NCCIH says short-term use of up to about 3 months appears safe for most adults, long-term safety data are lacking, ashwagandha should be avoided during pregnancy and while breastfeeding, and it may interact with thyroid, diabetes and blood-pressure medicines. Rare cases of liver injury have been reported.
The limits
We did not find a controlled trial of ashwagandha tea in women with PCOS. Its use in our blend rests on traditional use and its stress-related research, not on PCOS trial results.
Sources
Shatavari
Found in: PCOS Glow Tea
What the research found
Shatavari has a long history of use in Ayurvedic tradition for women’s reproductive health. Published human trials we found looked at other outcomes, such as breastfeeding and sexual wellness, rather than PCOS.
The limits
We did not find a controlled human trial of shatavari in PCOS. Its place in our blend reflects traditional use, and we do not claim research proves a PCOS benefit.
Green tea
Found in: Not an Organzo product — covered in our spearmint vs green tea comparison
What the research found
A 2021 systematic review and meta-analysis of randomized trials (Frontiers in Endocrinology) pooled 6 trials with 235 women with PCOS. Tea supplements, particularly green tea, reduced body weight, fasting blood glucose and fasting insulin compared with placebo. Effects on hormone levels needed further investigation.
A 2021 systematic review of green tea extract in PCOS (Reproductive Biology and Endocrinology) found promising results for weight and blood sugar and concluded that more studies are needed.
The limits
Most trials used green tea extract capsules rather than brewed tea, the trials were small, and green tea contains caffeine, which spearmint tea does not.
Sources
How to use this page
Read it alongside our Editorial Standards, which explain how we choose and describe sources. If you are pregnant, breastfeeding, have a medical condition or take medication, speak to your doctor before using any herbal tea. Found something wrong? Tell us through our contact page and we will check it.