NATURAL S-EQUOL · NaturEQ™

Taiyi Health natural S-equol
S-equol from a non-soy plant source

Non-soy plant origin; meets the requirements for soy-allergen-free labelling.

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≥99%
S-equol content · 100% S-configuration by chiral HPLC
Non-soy
Plant origin · carbon-14 report available on request
10 mg/day
Recommended dose · used in most human studies
Patent accepted
Invention patent for pelvic-floor use · own preclinical data

About S-equol

Not in soy itself: a metabolite made by gut bacteria

Soy foods do not contain S-equol. It is produced in the colon by specific bacteria that reduce daidzein, a soy isoflavone, in three enzymatic steps, and only people who carry these bacteria can make it.

Most people cannot produce it themselves

Reviews put the share of producers at 20–30% of Western adults and 50–60% of Asian adults who eat soy regularly; among U.S. subjects only 14–17%. Soy isoflavones work only in producers, so supplementing S-equol directly bypasses the dependence on gut flora.

One configuration, one receptor preference

The human body produces only the S-enantiomer. S-equol prefers estrogen receptor β, with roughly nine times the affinity for ERβ as for ERα: ERβ mediates tissue-protective and anti-proliferative signalling, while ERα drives proliferative effects in breast and endometrial tissue. This preference underlies both the benefits seen in studies and the safety profile. Chemically synthesised R/S racemic mixtures do not share it.

Rapid absorption, stable circulation: 10 mg/day reaches biologically meaningful plasma levels

Peak plasma concentration at about 1–3 hours, terminal half-life 7–8 hours, free fraction in plasma below 1%, and exposure proportional to dose across 10–320 mg. Half-life and high bioavailability together explain why most human studies use 10 mg/day.

Share of people able to produce equol
Western adults (reviews) 20–30% Asian adults (reviews) 50–60% Beijing · habitual diet 26.8% Beijing · after 3 days of soy 60.4% Hirosaki, Japan · survey 43.9% Australia · vegetarians 59% Australia · non-vegetarians 25% U.S. subjects 14–17%
The figures are the share of people found to produce equol in each study. The first two rows are regional consensus figures from reviews; the remaining six are measured values from individual studies. The two Beijing rows are the same adults: 26.8% on their habitual diet, rising to 60.4% after eating soy for three consecutive days, which shows how strongly the share depends on habitual soy intake; Australian vegetarians are higher than non-vegetarians, and U.S. subjects are the lowest. Producer status is defined by the urinary S-equol to daidzein ratio reaching a threshold.
Sources: Setchell 2010 (review) · Liu 2010 (Beijing, n=183) · Iino 2019 (Hirosaki, Japan, n=1,044) · Setchell & Cole 2006 (Australia, vegetarians n=29 / non-vegetarians n=12) · Akaza 2004 (U.S., controls 14%, cases 17%).

Existing third-party human research on S-equol

900+
Cumulative subjects in 9 human studies
9
Human studies · hot flushes · bone metabolism · skin · vaginal health · safety
7–8h
Terminal half-life · supports once-daily dosing
10–320mg
Single-dose range in Phase I · all tolerated
1yr
Longest randomised controlled trial · no change in endometrium or hormones
A summary of the nine human studies of S-equol (design, dose, outcomes, test material and source) is provided in the S-equol product brochure. None of the third-party studies above used NaturEQ™ as the test material, and some were funded by the relevant manufacturers; the mechanisms and findings described are a synthesis of published literature and do not constitute disease claims.

Taiyi Health's own pelvic-floor tissue study

In a rat model of stress urinary incontinence combining ovariectomy (simulating menopause) with vaginal distension (simulating childbirth injury), topical S-equol was applied for 28 days and evaluated at three levels: function, tissue and matrix. No existing oral or topical pelvic-floor ingredient has tissue-level evidence of this kind.

Function

Leak point pressure · pelvic floor muscle tone · day 14 and day 28
Leak point pressure (day 28)Near normal
Pelvic floor muscle toneRaised from day 14
Versus positive controlComparable

Tissue

Pubococcygeus muscle · H&E histopathology score
Score reduced, high-dose groupP<0.001
Fibre alignment · inflammatory infiltrationImproved

Matrix

Masson staining · share of abnormal collagen area
Abnormal collagen, high-dose groupNear normal
Fibrotic microenvironmentReduced
A Chinese invention patent application for this use was filed and accepted in September 2026
Animal study results do not represent effects in humans; the data are unpublished, full data are available under NDA, and a human study is being planned.

Specifications and dossier

NATURAL S-EQUOL · INGREDIENT

NaturEQ™ 99

For dietary supplements and functional foods · recommended dose 10 mg S-equol/day
S-equol content (HPLC)≥99.0%
S-configuration (chiral HPLC)100%
Plant sourceNon-soy · disclosed under NDA
Origin verificationCarbon-14 report · on request
Allergens100% free of soy-derived allergens
Dosage formsCapsules · tablets · gummies · beverages
TECHNICAL DOSSIER

Technical dossier

Provided after an NDA is signed
Specification · COAPer batch
Plant-origin reportCarbon-14 · on request
Structure and configurationChiral HPLC · NMR
Allergen statementFree of soy-derived allergens
Stability data · MSDSIncluded in the dossier
Own patents and dataPelvic-floor study · under NDA

Safety evidence for S-equol

Preclinical toxicology
Pure S-equol, 90-day subchronic study: NOAEL 250 mg/kg/day (female rats); acute oral dose of 2,000 mg/kg with no deaths or signs of toxicity (AnandaKumar 2024). For a fermented preparation, the NOAEL corresponds to about 12 mg/kg/day of pure equol (Yee 2008). In reproductive and developmental toxicity studies, the developmental NOAEL corresponds to 13 mg/kg/day of S-equol and the reproductive NOAEL to 6.5 mg/kg/day (Matulka 2009).
Genotoxicity
Three GLP assays, the Ames test, chromosomal aberration in human lymphocytes and rat bone-marrow micronucleus up to 2,000 mg/kg, all negative (pure S-equol, Schwen 2010); a separate set of three assays on a fermented preparation was also negative (Yee 2008).
Uterotrophic effects
No uterotrophic effect at the highest oral doses in rats and cynomolgus monkeys (Schwen 2012), consistent with expectations for a selective ERβ agonist.
Human safety
In Phase I studies, single doses up to 320 mg and repeated doses up to 160 mg twice daily for 14 days produced no significant drug-related adverse events (Jackson 2011). Across randomised trials there were no changes in sex hormones, gonadotropins, thyroid hormones, endometrial thickness or mammography (Aso 2012; Oyama 2012; Tousen 2011); one year of observation of a 98% purified preparation at 10 mg/day showed no significant change in endometrium, cervical smear or mammography (Yoshikata 2018).
Adverse events you should know about
In an 8-week U.S. trial (n=102, Jenks 2012), 47% of subjects reported at least one treatment-emergent adverse event, most commonly bloating (13% in the 10 mg group, 15% in the 20 mg group) and endometrial thickening (13% in the 10 mg group, judged not clinically significant); one case of breast cancer was diagnosed in the 20 mg group and judged unrelated to treatment. There were no clinically significant changes in laboratory values, ECG or vital signs.

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Frequently asked questions

Does NaturEQ™ contain soy?
No. NaturEQ™ is produced by fermentation from a non-soy plant precursor, with no soy raw material at any stage. The plant source and strain information are disclosed to partners under NDA, and an allergen verification statement is provided with the technical dossier.
How do you prove it is of natural origin rather than chemically synthesised?
Two tests. Carbon-14 (radiocarbon) analysis distinguishes plant-derived carbon from the fossil-derived carbon used in chemical synthesis; chiral HPLC and NMR demonstrate 100% S-configuration (R-configuration not detected), whereas chemical synthesis yields an R/S racemic mixture. The C14 report is available on request.
How does it differ from S-equol produced by soy fermentation?
The molecule is identical (S-(−)-equol). The difference lies in the supply chain: products fermented from soy carry soy in their ingredient source chain, which restricts "soy-free" labelling and allergen-free positioning; NaturEQ™ does not.
What is the recommended dose, and how long until effects are seen?
The recommended dose is 10 mg S-equol/day, the dose used in most human studies; the literature explores 10–40 mg/day. Randomised controlled trials mostly use a 12-week observation period, and one trial saw effects at 8 weeks; we suggest "12 weeks" as a reasonable expectation to set with consumers.
Is the safety data sufficient?
Preclinical: a 90-day NOAEL of 250 mg/kg/day for the pure compound, three GLP genotoxicity assays negative, and no uterotrophic effect in rats or cynomolgus monkeys. Human: no significant drug-related adverse events up to 320 mg in Phase I, and no abnormalities in sex hormones, thyroid hormones, endometrial thickness or mammography across randomised trials. One U.S. trial reported mild gastrointestinal events and endometrial thickening judged not clinically significant; both are listed in full in the safety section of this page.
Can men use it?
S-equol has anti-androgenic activity (it binds DHT), and animal studies point to potential in prostate health; randomised controlled trials in men are lacking. We present this as a research direction, not a recommended use.
How do I obtain the specification, COA, C14 report and samples?
Submit your company, role, target market and intended dosage form through the form above; the full technical dossier is provided after an NDA is signed. Samples are available to qualified B2B customers on request.