# Soyfem (Glycine max extract)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/soyfem
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-31
**Evidence Score:** 2 / 10
**Category:** Other
**Also Known As:** Glycine max extract, Soybean extract, Soy phytoestrogen extract, Glycine max, Soja extract, Dadou extract, Soybean isoflavone extract

## Overview

Soyfem is a standardized ethyl acetate extract of Glycine max (soybean) containing isoflavones, particularly genistein and daidzein, which act as selective estrogen receptor modulators (SERMs). Its primary mechanism involves binding to estrogen receptors alpha and beta, modulating downstream estrogenic activity in target tissues such as skin and reproductive organs.

## Health Benefits

• May support skin [collagen production](/ingredients/condition/skin-health) - ethyl acetate extract (200 mg/kg) significantly increased skin collagen layer thickness in rats (p<0.05) - Evidence: Preliminary (animal study only)
• May modulate estrogen receptor activity - reduced estrogen receptor-positive cells in rat skin tissue - Evidence: Preliminary (animal study only)
• Contains phytoestrogens that may support [hormonal balance](/ingredients/condition/hormonal) - isoflavones structurally similar to estrogenic steroids - Evidence: Theoretical (no human trials on Soyfem)
• May enhance bioavailability of certain medications through P-gp inhibition - genistein increased drug absorption by 53% AUC - Evidence: Preliminary (pharmacokinetic studies)
• Provides [antioxidant](/ingredients/condition/antioxidant) compounds including isoflavones, phytosterols, and other bioactives - Evidence: Theoretical (compositional analysis only)

## Mechanism of Action

Soyfem's bioactive isoflavones, primarily genistein and daidzein, bind to estrogen receptors ERα and ERβ with preferential affinity for ERβ, acting as selective estrogen receptor modulators (SERMs) that can produce tissue-specific agonist or antagonist effects. Genistein additionally inhibits tyrosine kinase and topoisomerase II enzymes, modulating cell proliferation pathways. In skin tissue, these compounds appear to upregulate collagen-synthesizing fibroblast activity while simultaneously reducing the proportion of estrogen receptor-positive epithelial cells, suggesting a dual regulatory role in skin homeostasis.

## Clinical Summary

Current evidence for Soyfem is limited to preclinical animal studies, with no published human clinical trials identified at this time. A rat model study demonstrated that oral administration of the ethyl acetate Glycine max extract at 200 mg/kg significantly increased dermal collagen layer thickness (p<0.05) compared to controls. The same study reported a reduction in estrogen receptor-positive cells in rat skin tissue, suggesting modulatory rather than purely stimulatory estrogenic activity. Until well-designed human randomized controlled trials are conducted, all efficacy claims must be considered preliminary and extrapolation to human dosing remains speculative.

## Nutritional Profile

Soyfem is a standardized extract of Glycine max (soybean) enriched in phytoestrogenic isoflavones. Key bioactive compounds include: • Isoflavones (primary actives): genistein (typically 40–60% of total isoflavones), daidzein (30–45%), and glycitein (5–15%), present in both aglycone and glycoside forms (genistin, daidzin, glycitin). Total isoflavone content in standardized extracts generally ranges from 40–80 mg per gram of extract, though exact concentration depends on extraction method and standardization. • The ethyl acetate fraction (referenced in collagen studies) is enriched in aglycone isoflavones and lower-molecular-weight polyphenols, which have higher bioavailability than glycoside-bound forms. • Additional bioactive compounds: soy saponins (group A and group B saponins), soy peptides, phytosterols (β-sitosterol, campesterol, stigmasterol — trace to low mg amounts depending on extraction), and phenolic acids (ferulic acid, p-coumaric acid in trace quantities). • As an extract (not whole soybean), macronutrient content is minimal — residual protein may be present but is not the primary functional component; fiber and fat content are negligible. • Mineral content is largely removed during extraction; trace amounts of potassium, magnesium, calcium, and iron may persist but are not clinically significant. • Bioavailability notes: Aglycone isoflavones (genistein, daidzein) are absorbed more rapidly and at higher rates than their glycoside conjugates. Daidzein is converted to equol by specific gut microbiota (only ~30–50% of individuals are 'equol producers'), which significantly impacts estrogenic bioactivity. Genistein has moderate oral bioavailability (~20–30% in humans) with extensive first-pass glucuronidation and sulfation. Co-administration with food or [probiotic](/ingredients/condition/gut-health)s may enhance isoflavone absorption. Half-life of circulating isoflavones is approximately 6–8 hours.

## Dosage & Preparation

No clinically studied dosage ranges for Soyfem in humans have been established. The only available data comes from animal studies using 200 mg/kg body weight of ethyl acetate extract, with isoflavone concentrations of approximately 48 mg/25 g soybeans. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Soyfem contains estrogenic isoflavones and is theoretically contraindicated or requires caution in individuals with estrogen receptor-positive cancers, uterine fibroids, or endometriosis, though direct human safety data for this extract are lacking. It may interact with tamoxifen, aromatase inhibitors, and other hormone therapies by competing at estrogen receptor binding sites, potentially diminishing or altering their therapeutic effects. Soy isoflavones can inhibit [thyroid](/ingredients/condition/hormonal) peroxidase activity, so individuals with hypothyroidism or those taking levothyroxine should exercise caution and consult a physician. Safety during pregnancy and lactation has not been established for this specific extract, and use is generally not recommended in these populations without medical supervision.

## Scientific Research

No human clinical trials, RCTs, or meta-analyses specifically on Soyfem were identified in the available research. Evidence is limited to one animal study in rats where ethyl acetate extract (200 mg/kg) significantly increased skin collagen layer thickness (p<0.05). No PubMed PMIDs for human trials on this branded extract were found.

## Historical & Cultural Context

While no specific historical context for the branded Soyfem extract was identified, Glycine max (soybean) has been used in Asian traditional medicine systems, particularly Chinese medicine, for millennia as both food and for lipid regulation. The traditional use duration and specific medicinal indications for the branded extract are not documented in the available research.

## Synergistic Combinations

Black cohosh, red clover, dong quai, vitamin D, calcium

## Frequently Asked Questions

### What is Soyfem and how does it differ from regular soy extract?

Soyfem is a specific ethyl acetate fraction of Glycine max (soybean) that concentrates isoflavone compounds such as genistein and daidzein, which are the primary bioactive SERMs. Unlike whole soy protein extracts or general isoflavone blends, the ethyl acetate extraction method selectively isolates polyphenolic compounds while reducing non-target constituents, potentially yielding a more standardized hormonal-support profile.

### Can Soyfem increase collagen production in skin?

Animal research using the ethyl acetate Glycine max extract at 200 mg/kg orally demonstrated a statistically significant increase in dermal collagen layer thickness in rats (p<0.05). The proposed mechanism involves isoflavone-driven stimulation of fibroblast collagen synthesis via ERβ activation in skin tissue. However, these findings have not yet been replicated in human clinical trials, so direct conclusions about collagen benefits in humans cannot currently be made.

### Is Soyfem safe for women with a history of breast cancer?

Soyfem contains genistein and daidzein, which bind estrogen receptors ERα and ERβ and may exert estrogenic activity in hormone-sensitive tissues. Women with estrogen receptor-positive breast cancer, or those in remission, are generally advised to avoid phytoestrogen-rich supplements unless explicitly cleared by an oncologist, as the tissue-specific effects of SERMs are complex and context-dependent. No human safety data specific to Soyfem in this population have been published.

### Does Soyfem interact with thyroid medications?

Soy isoflavones, including those in Soyfem, have been shown to inhibit thyroid peroxidase, an enzyme essential for thyroid hormone synthesis, which could theoretically impair thyroid function or interfere with levothyroxine absorption. Clinical studies on soy and thyroid suggest separating soy supplement intake from levothyroxine dosing by at least four hours to minimize absorption interference. Individuals with diagnosed hypothyroidism should consult their healthcare provider before using any isoflavone-containing supplement.

### What dosage of Soyfem has been studied?

The only published dosage data identified for this specific Glycine max ethyl acetate extract is 200 mg/kg body weight administered orally in a rat model, which demonstrated significant effects on skin collagen thickness and estrogen receptor expression. Direct human equivalent dosing cannot be reliably extrapolated from this rat study without allometric scaling validation and human pharmacokinetic data. No established human clinical dose has been confirmed through controlled trials as of the current evidence base.

### What is the difference between Soyfem and other soy isoflavone supplements?

Soyfem is a standardized ethyl acetate extract of Glycine max that has been specifically studied for skin collagen production, whereas many soy isoflavone supplements are designed primarily for menopausal symptom relief. The extraction method and concentration in Soyfem may differ significantly from conventional soy extract supplements, potentially affecting its bioavailability and target tissue effects. Soyfem's research focus has centered on dermatological and skin health applications rather than general hormonal balance.

### Is Soyfem safe to take during pregnancy and breastfeeding?

There is insufficient human safety data on Soyfem use during pregnancy and breastfeeding, and it should be avoided in these populations until more research is available. While soy is generally recognized as safe in food, concentrated extracts like Soyfem that may modulate estrogen receptor activity carry unknown risks to fetal development and nursing infants. Women planning pregnancy or currently pregnant/breastfeeding should consult their healthcare provider before using Soyfem.

### How strong is the current clinical evidence supporting Soyfem's benefits?

Current evidence for Soyfem is preliminary and limited to animal studies; human clinical trials have not yet been published to establish safety and efficacy in people. While rat studies showed significant increases in skin collagen layer thickness at 200 mg/kg doses, these animal results do not automatically translate to equivalent benefits in humans. Consumers should be aware that Soyfem's marketed benefits remain largely unproven in clinical human research.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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