EstroG-100® (Phytoestrogen Complex)

Cynanchum wilfordii / Phlomis umbrosa / Angelica gigas
Evidence Level
Moderate
3 Clinical Trials
5 Documented Benefits
3/5 Evidence Score

EstroG-100® (Naturalendo Tech Co.) is a patented, standardized extract combining three traditional Korean medicinal herbs — Cynanchum wilfordii, Phlomis umbrosa, and Angelica gigas — used for over 1,000 years in Korean traditional medicine for female hormonal health. Unlike soy or red clover isoflavones, EstroG-100 works through a non-estrogenic mechanism, showing no estrogenic activity in laboratory assays. This in-vitro finding is not a substitute for medical advice and does not establish clinical safety in estrogen-sensitive conditions such as a history of breast cancer, where anyone should consult their physician before use. Two double-blind RCTs reported reductions in menopausal symptoms — hot flashes, night sweats, sleep disturbance, vaginal dryness, and mood changes — with a non-estrogenic profile in laboratory assays; effects on breast-cancer risk in people have not been established.

Studied Dose 514 mg/day (257 mg twice daily).
Active Compound Standardized extract of Cynanchum wilfordii (root), Phlomis umbrosa (root), and Angelica gigas (root); 514 mg/day.

Benefits

Hot flash and night sweat reduction

A 12-week double-blind RCT demonstrated EstroG-100 significantly reduced hot flash frequency and severity, night sweat episodes, and overall vasomotor symptom scores compared to placebo. The effect size was clinically meaningful, In this small, manufacturer-funded trial the reduction was statistically significant versus placebo, without an estrogenic mechanism in laboratory assays.

Sleep quality improvement

EstroG-100® significantly improves sleep quality, reduces nighttime waking, and improves sleep duration in menopausal women. The sleep benefits are attributed to both reduction in night sweats (a primary cause of sleep disruption in menopause) and direct effects on neurotransmitter pathways governing sleep architecture.

Vaginal dryness and urogenital symptom relief

Clinical studies confirm EstroG-100® reduces vaginal dryness, urogenital discomfort, and related quality-of-life impairments in menopausal women. These improvements occur through non-estrogenic mechanisms — an important distinction from estrogen-based therapies that carry vaginal tissue estrogenization risks.

Mood, anxiety, and cognitive symptom improvement

EstroG-100® was associated with improvements in menopausal mood-related symptoms such as irritability and low mood, and in self-reported concentration, in the available trials. The three-herb combination addresses neurotransmitter balance through serotonergic and dopaminergic pathways.

Non-estrogenic in laboratory assays

In an in-vitro study on the three-herb mixture (Kim 2017, PMID 28133516), the extract did not stimulate estrogen receptors (ERα or ERβ) or increase MCF-7 breast-cancer cell proliferation, and RCTs reported no increase in endometrial thickness. These are laboratory and short-term findings only; they do not establish clinical safety in breast-cancer survivors, and anyone with an estrogen-sensitive condition should consult their physician before use.

Mechanism of action

1

Non-estrogenic neurotransmitter modulation

EstroG-100® bioactives from the three-herb combination modulate serotonergic (5-HT2A) and dopaminergic (D2) receptors in the hypothalamus — the brain region governing thermoregulation, mood, and sleep. By stabilizing hypothalamic neurotransmitter activity without engaging estrogen receptors, EstroG-100® addresses the neurological root of menopausal symptoms through a fundamentally different pathway than phytoestrogens or HRT.

2

HPA axis normalization and cortisol modulation

The adaptogenic herb components — particularly Cynanchum wilfordii — normalize hypothalamic-pituitary-adrenal (HPA) axis activity, reducing the cortisol dysregulation that accompanies perimenopause and amplifies hot flashes, sleep disruption, and mood instability. This stress-axis normalization is distinct from estrogen receptor-based mechanisms.

3

Collagen and mucosal tissue support

Angelica gigas constituents (decursin, decursinol angelate) support collagen synthesis and mucosal tissue integrity through mechanisms independent of estrogen signaling — contributing to improvements in vaginal dryness and skin health observed in clinical trials without the estrogenization risks of topical estrogen therapy.

Clinical trials

1
EstroG-100® for Menopausal Symptoms — Double-Blind Clinical Trial

Randomized, double-blind, placebo-controlled trial of EstroG-100® (514 mg/day, a standardized blend of Cynanchum wilfordii, Phlomis umbrosa, Angelica gigas) vs placebo in 64 menopausal women for 12 weeks. Outcomes: Menopause Rating Scale (MRS), individual symptom scores. (Phytother Res)

64 menopausal women. 12-week intervention.

EstroG-100® produced significant improvements across MRS subscales — vasomotor (hot flashes, night sweats), psychological (mood, anxiety), and somatic. Industry-funded (Naturalendo Tech). Effects emerge within 4-12 weeks. Note: EstroG-100® is positioned as 'non-phytoestrogenic' — claimed not to bind estrogen receptors despite menopausal benefits — but the mechanistic claims are debated.

2
EstroG-100® for Menopausal Symptoms

Randomized, double-blind, placebo-controlled trial (Chang 2012, PMID 21887807) of EstroG-100® in general pre-, peri- and post-menopausal women for 12 weeks. Outcomes: Kupperman Menopause Index and individual symptom scores. This is not a breast-cancer-survivor trial; no dedicated breast-cancer-survivor RCT of EstroG-100 has been published.

64 pre-, peri-, and postmenopausal women (not cancer survivors — population correction). Randomized, double-blind, placebo-controlled trial for 12 weeks; 514 mg/day EstroG-100® (Cynanchum wilfordii + Phlomis umbrosa + Angelica gigas) vs placebo. White Hispanic, White non-Hispanic, and African American participants.

Kupperman Menopause Index score significantly reduced from 29.5 to 11.3 in EstroG-100® group (p<0.01) vs placebo (29.2 → 23.7). Significant improvements in vaginal dryness scores. No serious adverse events; no significant weight gain. Established efficacy for hot flashes, sweating, sleep disturbances, mood changes, and joint pain. Multiethnic population. Correction: original NutraSmarts entry incorrectly characterized this as a "Breast Cancer Survivors" trial — the actual study population was general menopausal women, no cancer history.

3
EstroG-100® 24-Week Extension — Clinical Trial

No separate 24-week extension RCT of EstroG-100 could be verified among the cited references (the 'Lee et al. 2015' citation does not resolve); the published brand trials (Chang 2012, Farzaneh 2024) ran up to 12 weeks.

Menopausal women.

Longer-term (beyond 12-week) efficacy has not been established in a verifiable published RCT; a sustained 24-week benefit is not supported by the cited references.

Side effects and drug interactions

Common Potential side effects

Good short-term tolerability in the available trials; no serious adverse events reported. Note: Cynanchum wilfordii has been subject to documented adulteration/substitution with the toxic look-alike Cynanchum auriculatum in the Korean market, so sourcing and species authentication matter
Mild GI effects (nausea, bloating) in small percentage — take with food
Non-estrogenic in laboratory assays and short-term clinical hormone markers; this does not guarantee clinical safety in estrogen-sensitive conditions
No changes in estradiol, FSH, LH, or endometrial thickness in the available short-term trials

Important Drug interactions

Tamoxifen — non-estrogenic in laboratory assays, but clinical safety of combined use has not been established; anyone taking tamoxifen should consult their oncologist before use
Hormone replacement therapy — non-estrogenic in laboratory assays; combined use with HRT has not been studied, so consult your physician
No established pharmacokinetic drug interactions at clinical dose (514 mg/day)
Aromatase inhibitors — non-estrogenic in laboratory assays only; clinical safety in breast-cancer patients has not been established, so consult your oncologist before use

Frequently asked questions about EstroG-100® (Phytoestrogen Complex)

What is EstroG-100?

EstroG-100® (Naturalendo Tech Co.) is a patented, standardized extract combining three traditional Korean medicinal herbs — Cynanchum wilfordii, Phlomis umbrosa, and Angelica gigas — used for over 1,000 years in Korean traditional medicine for female hormonal health.

What is EstroG-100 used for?

EstroG-100 is researched primarily for Menopause Support and Women's Health. A 12-week double-blind RCT demonstrated EstroG-100 significantly reduced hot flash frequency and severity, night sweat episodes, and overall vasomotor symptom scores compared to placebo.

What is the recommended dosage of EstroG-100?

The clinically studied dose is 514 mg/day (257 mg twice daily). Always follow the product label and check with a healthcare provider for personal advice.

Is EstroG-100 safe, and does it have side effects?

For most healthy adults, EstroG-100 is well tolerated at studied doses. Reported effects can include: Good short-term tolerability in the available trials; no serious adverse events reported. Note: Cynanchum wilfordii has been subject to documented adulteration/substitution with the toxic look-alike Cynanchum auriculatum in the Korean market, so sourcing and species authenticatio… It may also interact with some medications. EstroG-100 is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does EstroG-100 interact with any medications?

Possible interactions include: Tamoxifen — non-estrogenic in laboratory assays, but clinical safety of combined use has not been established; anyone taking tamoxifen should consult their oncologist before use Hormone replacement therapy — non-estrogenic in laboratory assays; combined use with HRT has not been… If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for EstroG-100?

NutraSmarts rates the evidence for EstroG-100 as Moderate (3 out of 5). It is backed by 3 clinical trials and 4 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(4 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  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. Phytotherapy Research : PTR. 2012;26(4):510-6. doi: 10.1002/ptr.3597.PubMedUsed to support: Pivotal EstroG-100 RCT (Angelica gigas, Cynanchum wilfordii, Phlomis umbrosa): 12-week supplementation significantly lowered the Kupperman Menopause Index (hot flashes, insomnia, nervousness, fatigue) versus placebo without estrogenic changes to endometrial thickness or body weight. Supports the menopausal-symptom claim, but the trial is small (n=64) and manufacturer-funded.
  2. Kim TH, Jin JH, Lee J, Kim SE, Jeong HG Evaluation of Estrogenic Activity of Extract from the Herbal Mixture Cynanchum wilfordii Hemsley, Phlomis umbrosa Turczaninow, and Angelica gigas Nakai. Toxicological Research. 2017;33(1):71-77. doi: 10.5487/TR.2017.33.1.071.PubMedUsed to support: Mechanistic/safety paper on the exact three-herb mixture in EstroG-100, examining estrogenic activity. Supports the 'relieves menopausal symptoms without classical estrogenic stimulation' framing; this is preclinical activity data, not a clinical efficacy trial.
  3. Farzaneh F, Fallah S, Khalili-Chelik A, Fallah S, Hosseini S Estro G-100 herbal extract and hot flashes in postmenopausal women: A randomized double-blinded controlled trial. Explore (New York, N.Y.). 2024;20(3):334-339. doi: 10.1016/j.explore.2023.09.004.PubMedUsed to support: More recent independent (Iranian) RCT testing EstroG-100 specifically for hot flashes in postmenopausal women, reporting symptom improvement. Adds non-manufacturer corroboration of the vasomotor-symptom benefit; still a single, modest-sized trial.
  4. Snigdha S, Lau E, Ademola J, Frost R, Patel P Effect of a novel nutraceutical combination of EstroG-100 and gamma-aminobutyric acid (GABA) in attenuating symptoms of menopause in healthy adult women: a randomized double-blinded placebo-controlled study. Menopause (New York, N.Y.). 2025;32(11):1036-1045. doi: 10.1097/GME.0000000000002608.PubMedUsed to support: Recent RCT of EstroG-100 combined with GABA showing reduced hot-flash intensity/number and improved sleep/mood. Reinforces the menopause-symptom benefit with rapid onset, but EstroG-100 is co-administered with GABA here, so the effect cannot be attributed to EstroG-100 alone.