What is it used for?
Helps to attenuate/reduce/decrease bone (mineral density (BMD)) loss in postmenopausal women when used in conjunction with adequate amounts of calcium and vitamin D [Source note 2].
May reduce severe and frequent menopausal symptoms (such as hot flashes and/or night sweats) (D'Anna et al. 2007; Nahas et al. 2007; Williamson-Hughes et al. 2006; Crisafulli et al. 2004; Albert et al. 2002; Han et al. 2002; Scambia et al. 2000; Upmalis et al. 2000; Albertazzi et al. 1998).
What this guide covers
Restrictions when this reference is combined with other references (source review category II and III):
Specific combination rules apply to active ingredients with estrogenic (e.g., red clover isoflavone extract, soybean extracts and isolates and dong quai - Angelica sinensis) or anti-estrogenic effects [e.g., indole-3-carbinol (I3C) and, diindolylmethane (DIM)]. Consult the reference combination guide for more information.
Who does this guide cover?
Perimenopausal women; Postmenopausal women (D'Anna et al. 2007; Nahas et al. 2007; Crisafulli et al. 2004; Albert et al. 2002; Faure et al. 2002; Han et al. 2002; Scambia et al. 2000; Upmalis et al. 2000; Albertazzi et al. 1998).
How is it taken?
Oral
Which forms are covered?
this reference excludes foods or food-like dosage forms as indicated in the Compendium of references Guidance Document.
Quantities
Reduction of BMD loss
Glycine max, Soy isoflavone extract
Methods of preparation: Standardized extracts
75 - 125 milligrams of total Aglycone Isoflavone Equivalents (AIE), per day [Source note 3].
Soy protein concentrate, Soy protein isolate
Methods of preparation: Standardized extracts
75 - 125 milligrams of total AIE, per day; Not to exceed 35 grams of soy protein concentrate and/or isolate, per day [Source note 4].
Genistein, Genistin
75 - 125 milligrams of total AIE, per day [Source note 5].
Reduction of menopausal symptoms
Glycine max, Soy isoflavone extract
Methods of preparation: Standardized extracts
30 - 125 milligrams of total AIE with a minimum of 15 milligrams of AIE from genistein and/or genistin, per day (D'Anna et al. 2007; Nahas et al. 2007; Williamson-Hughes et al. 2006; Crisafulli et al. 2004; Albert et al. 2002; Han et al. 2002; Scambia et al. 2000; Upmalis et al. 2000; Albertazzi et al. 1998).
Soy protein concentrate, Soy protein isolate
30 - 125 milligrams of total AIE with a minimum of 15 milligrams of AIE from genistein and/or genistin, per day; Not to exceed 35 grams of soy protein concentrate and/or isolate, per day (CNF 2024; D'Anna et al. 2007; Nahas et al. 2007; Williamson-Hughes et al. 2006; CPS 2004; Crisafulli et al. 2004; Albert et al. 2002; Han et al. 2002; Scambia et al. 2000; Upmalis et al. 2000; Albertazzi et al. 1998).
Genistein, Genistin
15 - 125 milligrams of total AIE, per day ( D'Anna et al. 2007; Nahas et al. 2007; Williamson-Hughes et al. 2006; Crisafulli et al. 2004; Albert et al. 2002; Han et al. 2002; Scambia et al. 2000; Upmalis et al. 2000; Albertazzi et al. 1998).
How is it used?
Take a few hours before or after taking other medications or health products [Source note 6].
How long is it used?
Reduction of BMD loss
Use for at least 6 months to see beneficial effects [Source note 7].
Reduction of menopausal symptoms
Use for at least 2 weeks to see beneficial effects (D'Anna et al. 2007; Nahas et al. 2007; Crisafulli et al. 2004; Han et al. 2002; Scambia et al. 2000; Upmalis et al. 2000; Albertazzi et al. 1998).
All uses
Ask a healthcare professional for use beyond 1 year [Source note 8].
Warnings and precautions
All products
Ask a healthcare professional before use if you are not up-to-date on mammograms and gynaecological evaluations [Source note 9].
Ask a healthcare professional if symptoms worsen.
Ask a healthcare professional before use if you are taking blood thinners or any hormone replacement therapy [Source note 10].
Ask a healthcare professional before use if you have a liver disorder or a history of hormonal or gynaecological disease [Source note 11].
When should it be avoided?
Do not use if you have or had breast cancer or tumours or a predisposition to breast cancer, as indicated by an abnormal mammogram or biopsy, or a family member with breast cancer [Source note 12].
Possible side effects
Stop use and ask a healthcare professional if new symptoms develops such as breast pain, a recurrence of menstruation, uterine spotting or liver-related symptoms (e.g. abdominal pain, jaundice, dark urine) [Source note 13].
Storage
Must be established in accordance with the requirements described in the applicable product regulations.
Appendix 1: Definitions and Conversion Factors
Definitions:
Aglycone Isoflavone Equivalents (AIE):
The maximum amount of bioavailable isoflavone upon ingestion. The glycoside forms of the isoflavones must first be cleaved to the aglycone form before they can be absorbed. As such, simple addition of aglycone and glycoside forms of isoflavone quantities, without taking into consideration the biochemical transformation of the isoflavones, will overestimate bioavailable quantities by almost a factor of two [Source note 15].
Conversion factors:
The quantity of isoflavones must always be determined in terms of AIE quantities (i.e. in terms of genistein, daidzein, and/or glycitein) for each of the glycoside, acetyl glycoside, malonyl glycoside and/or aglycone forms present in the product.
| Isoflavone (1 mg) | Aglycone Isoflavone Equivalent (mg AIE) quantity |
|---|---|
| Genistein | 1.0 |
| Genistin | 0.625 |
| Malonyl genistin | 0.521 |
| Acetyl genistin | 0.570 |
| Daidzein | 1.0 |
| Daidzin | 0.611 |
| Malonyl daidzin | 0.506 |
| Acetyl daidzin | 0.555 |
| Glycitein | 1.0 |
| Glycitin | 0.637 |
| Malonyl glycitin | 0.534 |
| Acetyl glycitin | 0.582 |
Example of using the Aglycone Isoflavone Equivalent (AIE) conversion factors: Converting glycoside quantity into quantity of AIE (mg):
Convert 20 mg of genistin into mg AIE:
= 20 mg x 0.625 mg AIE/mg genistin
= 12.5 mg AIE genistin
Appendix 2: Calculating Total Isoflavones and Reporting Amounts on the product documentation Form
Example of a 30 g/day soy protein concentrate product:
For a product with a claim for the reduction of menopausal symptoms, the amount of protein, total isoflavones, and genistein/genistin compounds must be reported on the product documentation form.
Calculating total isoflavones (mg AIE)
Convert genistin, genistein, malonyl genistin, acetyl genistin, daidzein, and daidzin AIE quantities into quantities of total isoflavones in AIE (mg):
= 12.5 mg AIE genistin + 10 mg AIE genistein + 1 mg AIE malonyl genistin + 1 mg AIE acetyl genistin + 6.1 mg AIE daidzin + 5 mg AIE daidzein
= 35.6 mg AIE total isoflavones
Calculating genistein/genistin compounds (mg AIE)
Convert genistein, genistin, malonyl genistin, and acetyl genistin AIE quantities into quantities of total isoflavones in AIE (mg):
= 12.5 mg AIE genistin + 10 mg AIE genistein + 1 mg AIE malonyl genistin + 1 mg AIE acetyl genistin
= 24.5 mg AIE genistein/genistin compounds
Reporting on the product documentation form should be as follows:
Proper Name: Soy protein concentrate
Common Name: Soy protein concentrate
Quantity per dosage unit: 30 g
Source Material: Glycine max - Seed
Potencies: Total isoflavones: 35.6 mg AIE; Genistein/genistin: 24.5 mg AIE
Example of a 30 mg/day genistein/genistin isolate product:
For a product with a claim for the reduction of menopausal symptoms, the amount of genistein/genistin must be reported on the product documentation form.
Reporting on the product documentation form should be as follows:
Proper Name: Genistein / Genistin
Common Name: Genistein / Genistin
Quantity per dosage unit: 30 mg AIE
Source Ingredient: Soy isoflavone extract or Soy protein concentrate or Soy protein isolate or None
Source Material: Glycine max - Seed
Potencies: None
Preparation details
Ingredient identity, preparation requirements, and other details that define the scope of this guide.
Ingredients and preparations
| Proper name(s) | Common name(s) | Source information / Source ingredient(s) | Source information / Source material(s) | Source information / Part(s) |
|---|---|---|---|---|
| Genistein | Genistein | Glycine max | Seed |
| 7-(beta-D-glucopyranosyloxy)-3-(4- hydroxyphenyl)-4H-1-Benzopyran-4-one |
| Genistin | Glycine max | Seed |
| Glycine max |
| N/A | Glycine max | Seed |
| Soy isoflavone extract | Soy isoflavone extract | N/A | Glycine max | Seed |
| Soy protein concentrate | Soy protein concentrate | N/A | Glycine max | Seed |
| Soy protein isolate¹ | Soy protein isolate | N/A | Glycine max | Seed |
References: Proper names: source ingredient database 2024, USDA 2024, Evans et al. 2007, Newton et al. 2006, Roudsari et al. 2005, Arjamandi et al. 2003, Yamori et al. 2002, Alekel et al. 2000, Scambia et al. 2000, Upmalis et al. 2000 Wangen et al. 2000, Potter et al. 1998; Common names: source ingredient database 2024, Evans et al. 2007, Newton et al. 2006, Roudsari et al. 2005, Arjamandi et al. 2003, Yamori et al. 2002, Alekel et al. 2000, Wangen et al. 2000, Potter et al. 1998; Source information: source ingredient database 2024, USDA 2024, D'Anna et al. 2007, Evans et al. 2007, Nahas et al. 2007, Newton et al. 2006, Ye et al. 2006, Roudsari et al. 2005, Crisafulli et al. 2004, Harkness et al. 2004, Kreijkamp-Kaspers et al. 2004, Arjamandi et al. 2003, Uesugi et al. 2003, Han et al. 2002, Albert et al. 2002, Faure et al. 2002, Yamori et al. 2002, Alekel et al. 2000, Wangen et al. 2000, Albertazzi et al. 1998, Potter et al. 1998.
¹For isolate, the potency information should be equivalent to 90% or more protein on a dry weight basis.
Other ingredients
Must be chosen from the current source ingredient database and must meet the limitations outlined in the database.
Preparation and quality requirements
The finished product specifications must be established in accordance with the requirements described in the source authority source’s product quality guidance.
The active ingredient must comply with the requirements outlined in the source ingredient database.
For an accurate measure of specific isoflavones in AIE, follow the methods outlined in AOAC 2008.03 [Source note 14].
Guide change history
Updates to this SupplementSafety.org guide.
Minor updates
Updated guide wording, organization, and source presentation. Added our editorial change history.
Initial release
Initial SupplementSafety.org guide prepared from source reference material.
Validation: Not yet completed. Editorial updates do not constitute clinical validation.
Sources
Source information
This guide organizes source material about uses, preparations, amounts, and precautions. Read the conditions alongside each statement; the information may apply only to particular preparations or populations.
The source document includes supporting references. We have not independently summarized or assessed every cited study for this guide.
- Source document version
- May 29, 2026
- Source captured
- Aug 15, 2026
- Editorial work
- Editorial preparation. Independent clinical review has not been recorded for this guide.
Full citations are available through the link above. Verification is required to open them; reading this guide does not require verification.
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