Cited by 34Phytoestrogen effects and researchReproductive Biology and FertilitySoybean genetics and cultivation

The role of soy and soy isoflavones on women’s fertility and related outcomes: An update

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Rizzo, Gianluca, Feraco, Alessandra, Storz, Maximilian Andreas, Lombardo, Mauro·2022·Journal of Nutritional Science

Abstract

Abstract Soy is a key food in human nutrition. It is widely used in eastern traditional cuisine and it has recently diffused among self-conscious and vegetarian diets. The success of soy mainly depends on versatility and supposed healthy properties of soy foods and soy components. Meanwhile, the possible influence on endocrine system, in particular by isoflavones, raised concerns among some researchers. The present paper aims to conduct a review of available data on the effect of soy, soy foods and soy components on women's fertility and related outcomes. Eleven interventional studies, eleven observational studies and one meta-analysis have been selected from the results of queries. A weak, not clinically relevant effect has been highlighted on cycle length and hormonal status. However, a suggestive positive influence has been shown among women with fertility issues and during assisted reproductive technologies. Overall, soy and soy components consumption do not seem to perturb healthy women's fertility and can have a favourable effect among subjects seeking pregnancy. However, because of the paucity of studies exploring the impact of soy intake on women's fertility, as well as the limited population sample size, the frequently incomplete specimens’ collection to investigate all cycle phases and the insufficient characterisation of participants, the evidence is suggestive and it needs further in-depth research taking into account all these aspects.

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Crossref · 10.1017/jns.2022.15

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  • Some studies have suggested that phytoestrogens reduce total and free testosterone and may increase sex hormone binding proteins, which may lead to lower free testosterone levels, but other studies have not found significant changes.

    “Some studies have suggested that phytoestrogens reduce total and free testosterone and may increase sex hormone binding proteins, which may lead to lower free testosterone levels, but other studies have not found significant changes [51].”

    From Prevention of Diet-Induced Obesity by Phytoecdysteroids 20-Hydroxyecdysone and Calonysterone—Unexpected Modulation of Androgen Balance in Normal and Obese Rats (2026) · cites this paper as [51]

    In Results and discussion > Polycystic ovary syndrome (page not available), the review reports lower total testosterone and higher SHBG after soy isoflavones in one trial, and an association between equol production and lower total and free testosterone in another cohort. It also reports studies with no significant change in free testosterone or other androgen measures. The cited passages do not establish that increased SHBG caused lower free testosterone; the reported findings are chiefly from women with PCOS, a limitation the broad claim omits. (LLM, conf=0.84)

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Authors
Rizzo, G., Feraco, A., Storz, M. A., & Lombardo, M.
Affiliations
  • San Raffaele University of Rome (IT)
  • University of Freiburg (DE)
Corresponding author
Storz, Maximilian Andreas
Venue
Journal of Nutritional Science
Published
2022
Volume
11
Pages
e17-e17
ISSN
2048-6790 (ISSN-L)
OpenAlex
W4220693845
Cited by
34
References
93
Citations by year
2026: 5 · 2025: 8 · 2024: 7 · 2023: 12 · 2022: 2
FWCI
1.19
Type
journal article
Language
en
Open access
Locations
  • Journal of Nutritional Science (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
Funders
  • University of Cambridge
  • Albert-Ludwigs-Universität Freiburg
Topics
  • Health Sciences › Medicine › Pathology and Forensic Medicine › Phytoestrogen effects and research
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Reproductive Biology and Fertility
  • Life Sciences › Agricultural and Biological Sciences › Plant Science › Soybean genetics and cultivation
Keywords
soybean, soy isoflavones, female fertility, menstrual cycle length, hormonal status, assisted reproduction, endocrine disruption, soy products, vegetarian diet
MeSH terms
Female, Fertility, Humans, Isoflavones

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