Written by Shereen, Product Management Associate · Updated 11 November 2026
What is EstroG-100, and does it help with hot flushes?
EstroG-100® is a patented extract of three herbs long used in Korea and China: Cynanchum wilfordii, Phlomis umbrosa and Angelica gigas. In a 12-week placebo-controlled trial, women taking 514 mg a day saw hot flushes and sweats ease by week 6, with better sleep and mood and less tiredness. Our Herbal Harmony: Meno Rebalance has 514 mg in every scoop.
This article is for you if: you're in perimenopause or menopause, hot flushes or night sweats are getting in the way of your days or your sleep, and you've seen EstroG-100® on a label and want to know what it is and what the trials found.
EstroG-100® is a herbal extract that has been tested in women before, during and after menopause, in the US, South Korea, Iran and India. Here's what it's made from, what those 12-week trials found for hot flushes and other symptoms, how well it was tolerated, and how to fit it into your day.
→ See Herbal Harmony: Meno Rebalance, our daily EstroG-100® scoop for perimenopause and menopause
In this article
What is EstroG-100 made from?
EstroG-100® is a herbal extract, not a hormone. It's made from the roots of three plants, Cynanchum wilfordii, Phlomis umbrosa and Angelica gigas, which have been used as foods and herbal remedies in Korea and China for several hundred years.[1]
In the first US trial, the three roots were mixed in almost equal parts (32.5%, 32.5% and 35% by weight), extracted in hot water and dried to a powder. Each tablet held 257 mg of that powder, and women took one tablet twice a day, which gives 514 mg a day.[1]
You may wonder whether it changes your hormone levels. In that trial, oestradiol (the main form of oestrogen) and FSH in the EstroG-100® group did not change significantly over 12 weeks.[1] A 2022 trial in South Korea also found no significant change in oestradiol, FSH or the thickness of the womb lining compared with placebo.[2]
Does EstroG-100 help with hot flushes?
Yes. In two placebo-controlled trials, hot flushes improved more with EstroG-100® than with placebo, with the difference showing by week 6.
- US trial, 2012. 64 women before, during and after menopause took 514 mg of EstroG-100® or a placebo every day for 12 weeks. Their average Kupperman index score, which rates 11 common menopause symptoms, fell from 29.5 to 13.6 by week 6 and to 11.3 by week 12. On placebo it went from 29.2 to 23.7. The score for hot flushes and sweats improved significantly more than with placebo at weeks 6 and 12, and so did sleep, nervousness, low mood, dizziness and tiredness.[1]
- Iran trial, 2024. 120 postmenopausal women with hot flushes were randomly given two capsules of EstroG-100® or two placebo capsules a day for 12 weeks, and 70 of them completed the final analysis. By week 6, the placebo group reported significantly more mild, moderate and severe hot flushes than the EstroG-100® group.[3]
How do the EstroG-100 trials compare?
These four trials each tested EstroG-100® over 12 weeks, in the US, South Korea, Iran and India.
| Study | Who took part | Daily dose | Length | Main result |
|---|---|---|---|---|
| Chang et al., 2012 (US) | 64 women before, during and after menopause | 514 mg (257 mg twice a day) | 12 weeks | Symptom score down about 62%, against about 19% on placebo; hot flushes, sleep, mood and vaginal dryness improved more than with placebo |
| Kim et al., 2022 (South Korea) | 105 women aged 40 to 70 with moderate to severe symptoms | 514 mg (one pill twice a day) | 12 weeks | Overall symptom score fell more than with placebo by week 12; tiredness, joint and muscle aches, and numbness and tingling eased more than with placebo from week 4 |
| Farzaneh et al., 2024 (Iran) | 120 postmenopausal women with hot flushes (70 in the final analysis) | Two capsules | 12 weeks | Fewer mild, moderate and severe hot flushes than with placebo by week 6 |
| Kirubamani et al., 2023 (India) | 60 postmenopausal women | Twice a day (no placebo group) | 12 weeks | Symptom scores improved by week 6 and further by week 12; 96.5% were satisfied with the results |
Sources: the published trials listed in the References.[1] [2] [3] [4]
Is EstroG-100 safe?
The US, Korean and Indian trials found it well tolerated. In the US trial, no adverse events were seen or reported by women taking EstroG-100®, and liver enzymes, kidney function and blood fats stayed steady.[1] In the Korean trial, every adverse event in the EstroG-100® group was mild, and adverse events were not significantly more common than on placebo.[2] The Indian study reported no side effects.[4]
The US trial didn't include women with a history of hormone-dependent cancer.[1] If that applies to you, or you take medication, speak to your doctor before you start. Herbal Harmony: Meno Rebalance is not advised during pregnancy or breastfeeding. Our guide to Herbal Harmony: Meno Rebalance side effects and ingredients also covers our lab tests.
Where does EstroG-100 fit in your routine?
EstroG-100® works as a steady daily habit. In every trial, women took it each day for 12 weeks, and in the US, Korean and Indian trials, symptom scores kept improving up to week 12.
Our Herbal Harmony: Meno Rebalance gives you 514 mg of EstroG-100® in every scoop, the same daily amount used in the US and Korean trials. Each 13 g scoop also has iron and black pepper extract, in a longan and red date drink with about 1 g of sugar. Mix one scoop with 300 to 350 ml of water and drink it before breakfast or before bed. It's halal-certified by JAKIM. Give it at least a month of daily use; we recommend 3 months for the best results.
Simple habits may help too, such as a cool bedroom and light layers you can take off. Our guide to hot flushes and night sweats in perimenopause covers what else may help.
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Related reading: Hot flushes and night sweats: what actually helps in perimenopause · Does Herbal Harmony: Meno Rebalance have side effects? · Sleep in perimenopause: why it falls apart and what may help
Frequently asked questions
How long does EstroG-100 take to work?
In the US trial, average symptom scores had already dropped by week 6 and kept improving to week 12. The Iran trial also saw fewer hot flushes by week 6. Take it every day for at least 6 to 12 weeks before you judge it.
Can I take EstroG-100 with HRT?
The US and Korean trials left out women who had used hormone products in the previous 3 months, so they didn't test EstroG-100® alongside hormone replacement therapy (HRT). If you take HRT or any hormonal treatment, ask your doctor before adding it.
Is EstroG-100 only for women after menopause?
No. The US trial included women before, during and after menopause, and the Korean trial enrolled women aged 40 to 70 with moderate to severe symptoms. If you're in perimenopause and having hot flushes, it may suit you too.
Does EstroG-100 cause weight gain?
Not in the trials that measured it. Women taking EstroG-100® in the US trial didn't gain weight over 12 weeks. In the Korean trial, weight and body mass index didn't change differently from placebo, and the Indian study found no change in body mass index.
Key takeaways
- EstroG-100® is a patented hot-water extract of three herb roots: Cynanchum wilfordii, Phlomis umbrosa and Angelica gigas.
- In a 12-week placebo-controlled trial, 514 mg a day cut average menopause symptom scores by about 62%, against about 19% on placebo.
- Two placebo-controlled trials found hot flushes improved more than with placebo by week 6.
- Oestradiol and FSH didn't change significantly in the US and Korean trials, and the trials that reported on safety found it well tolerated.
- Herbal Harmony: Meno Rebalance has 514 mg of EstroG-100® in every scoop, the daily amount used in the US and Korean trials.
About the author: Shereen is a Product Management Associate at The Purest Co. A Master's graduate in Pharmacy from Monash University, she brings four years of research experience to product development, with a focus on evidence-based, thoughtfully formulated supplements that support everyday wellbeing.
References
[1] Chang A, Kwak BY, Yi K, Kim JS. The effect of herbal extract (EstroG-100) on pre-, peri- and post-menopausal women: a randomized double-blind, placebo-controlled study. Phytother Res. 2012.
[2] Kim T, Ryu KJ, Lee S, Lee DJ, Seo SK. A 12-week, multi-center, double-blind, randomized, placebo-controlled clinical trial for the evaluation of the efficacy and safety of the herbal extract (EstroG-100®) on menopausal symptoms. J Reprod Med Gynaecol Obstet. 2022.
[3] Farzaneh F, Fallah G, Khalili-Chelik A, Fallah A, Hosseini M. Estro G-100 herbal extract and hot flashes in postmenopausal women: a randomized double-blinded controlled trial. Explore (NY). 2024.
[4] Kirubamani H, Ahire P, Stalin C. Evaluation of efficacy and safety of EstroG-100® in alleviating menopausal symptoms in postmenopausal women in India: a prospective, single-center, single-arm, interventional study. J Midlife Health. 2023.
These statements have not been evaluated by any regulatory authority. This product is not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary. Consult a healthcare provider before use if you are pregnant, breastfeeding, or on prescribed medication.