Ingredient Explained · Women's Midlife
S-Equol vs. Genistein: Two Different Ingredients, One Licensed Formula
Genistein is a soy isoflavone. S-equol is a different molecule that certain intestinal bacteria can produce from daidzein, another soy isoflavone.
Each capsule of DR.MORGAN S-EQUOL PLUS contains 10 mg of synthetic S-equol and 16.7 mg AIE of genistein sourced from soybean seed. These two ingredient identities do not establish that the combination works better than either ingredient alone.
Key points
- Some intestinal bacteria can make S-equol from daidzein. Genistein is a separate soy isoflavone.
- Clinical trials have studied S-equol-containing preparations and genistein under different conditions.
- The cited studies do not show synergy or superiority for the finished DR.MORGAN formula.
- Health Canada NPN 80143622 identifies this product’s licensed ingredients, authorized use, directions and risk information.
Scientific background
Soybeans contain several isoflavones, including daidzein and genistein. Certain intestinal bacteria convert daidzein into S-equol through several metabolic steps. People vary in their capacity to make S-equol. Genistein is chemically distinct from both daidzein and S-equol.
Laboratory studies have examined how these compounds interact with estrogen receptors. Those experiments can help researchers investigate biological activity. Menopausal symptoms are clinical outcomes that require separate study.
Taking already-formed S-equol supplies the molecule directly, without the initial bacterial conversion of daidzein. Absorption, metabolism and individual differences still matter.
What the research examined
S-equol formation and molecular identity
Setchell and colleagues used chiral chromatography and mass spectrometry to distinguish S-equol from R-equol. They incubated human intestinal bacteria with daidzein in the laboratory and measured estrogen receptor binding. They also assessed how both forms were absorbed and processed after single oral doses in three healthy adults. That small component measured pharmacokinetics.
Clinical research involving S-equol
Aso and colleagues conducted a randomized, double-blind, placebo-controlled trial in 160 postmenopausal Japanese women classified as equol non-producers. The external fermented soy germ preparation, SE5-OH, supplied 10 mg of S-equol daily in two doses over 12 weeks. It also contained other isoflavones, including genistein. The symptom analysis included the 126 participants who completed the trial.
Clinical research involving genistein
D’Anna and colleagues studied a genistein intervention at 54 mg daily over 12 months in a randomized, double-blind, placebo-controlled study. The parent trial randomized 389 postmenopausal women. The hot-flush analysis covered the subgroup of 247 participants with symptoms at baseline. Both groups received calcium carbonate and vitamin D.
What the studies found
Setchell and colleagues identified S-equol as the form produced in the daidzein incubation and observed differences in estrogen receptor binding between the two forms. Aso and colleagues reported a greater decrease in daily hot-flush frequency with SE5-OH than with placebo among trial completers at week 12. D’Anna and colleagues reported lower hot-flush frequency with the genistein intervention than with placebo in the subgroup studied at 12 months.
These findings apply to their respective preparations and study populations. A clinical result with 54 mg of genistein daily cannot be assumed for the licensed 16.7 mg AIE in this formula. The SE5-OH results likewise cannot be transferred to a separate formula containing synthetic S-equol and soybean-derived genistein.
What the studies do not establish
None of the cited studies tested the finished DR.MORGAN S-EQUOL PLUS formula. The studies do not establish synergy, clinical superiority over either ingredient alone, enhanced absorption, stronger estrogen receptor activity for the combination or a consistent response across consumers. Each question would require a study designed to answer it.
Limitations
The cited studies used different preparations, doses, populations and durations. Aso enrolled Japanese equol non-producers, and the symptom analysis excluded 34 of the 160 randomized participants. Otsuka Pharmaceutical supplied SE5-OH and funded the study. Takeshi Aso and Hiroaki Ohta disclosed consulting fees from Otsuka.
D’Anna’s hot-flush analysis used a subgroup of the parent trial. Neither trial compared the licensed DR.MORGAN combination directly with either of its ingredients. The studies do not establish the long-term clinical safety of the finished DR.MORGAN formula. This article does not include a formal systematic assessment of risk of bias.
Evidence context
Ingredient Evidence
Research on molecular identity, receptor binding and pharmacokinetics helps explain the differences between these compounds. The D’Anna trial adds human evidence for the specific genistein intervention it studied.
Branded Ingredient Evidence
The Aso trial investigated SE5-OH, an external S-equol-containing preparation with its own composition. Its results apply to that preparation and the population studied.
Finished-product Evidence
The cited studies were not conducted on the finished DR.MORGAN S-EQUOL PLUS product.
Licensed Product Information
Health Canada NPN 80143622 identifies the product’s authorized use, medicinal ingredients, directions and risk information. The licence and the published research answer different questions.
Relationship to DR.MORGAN
DR.MORGAN S-EQUOL PLUS is a licensed Canadian natural health product with two medicinal ingredients.
- S-equol: 10 mg per capsule. Source: synthetic S-equol.
- Genistein: 16.7 mg AIE per capsule. Source: Glycine max (soybean) seed.
AIE means aglycone isoflavone equivalents. The formula contains soybean-derived genistein.
Authorized use and directions
Authorized use. May reduce severe and frequent menopausal symptoms (such as hot flashes and/or night sweats).
Recommended dose. Menopausal and postmenopausal women aged 18 years and older take one capsule orally once daily, a few hours before or after other medications or health products. Use for at least two weeks to see beneficial effects. Ask a health care practitioner about use beyond one year.
Warnings and contraindications
Ask a health care practitioner before use if your mammograms or gynaecological evaluations are not up to date, if you take blood thinners or hormone replacement therapy, or if you have a liver disorder or a history of hormonal or gynaecological disease.
Ask a health care practitioner if symptoms worsen.
Do not use if you have or have had breast cancer or tumours, or if you have a predisposition to breast cancer as indicated by an abnormal mammogram or biopsy, or by a family member with breast cancer. Stop use and ask a health care practitioner if new symptoms develop, including breast pain, a recurrence of menstruation, uterine spotting or liver-related symptoms such as abdominal pain, jaundice or dark urine.
Read the complete licensed product information and current product label before use. This article provides scientific education and does not assess individual suitability.
Last reviewed .
References
- Setchell KDR et al. S-equol, a potent ligand for estrogen receptor beta, is the exclusive enantiomeric form of the soy isoflavone metabolite produced by human intestinal bacterial flora. American Journal of Clinical Nutrition. 2005;81(5):1072–1079. DOI 10.1093/ajcn/81.5.1072. PubMed 15883431.
- Setchell KDR, Clerici C. Equol: history, chemistry, and formation. Journal of Nutrition. 2010;140(7):1355S–1362S. DOI 10.3945/jn.109.119776. PubMed 20519412. Background review.
- Aso T et al. A natural S-equol supplement alleviates hot flushes and other menopausal symptoms in equol nonproducing postmenopausal Japanese women. Journal of Women’s Health. 2012;21(1):92–100. DOI 10.1089/jwh.2011.2753. PubMed 21992596 · Publisher full text.
- D’Anna R et al. Effects of the phytoestrogen genistein on hot flushes, endometrium, and vaginal epithelium in postmenopausal women: a 1-year randomized, double-blind, placebo-controlled study. Menopause. 2007;14(4):648–655. DOI 10.1097/01.gme.0000248708.60698.98. PubMed 17251874.
- Health Canada. Licensed Natural Health Products Database. S-EQUOL PLUS product licence, NPN 80143622.
- DR.MORGAN. S-EQUOL PLUS Product Reference.