DefinePK

Abstract

Background: Infertility is the rapidly growing public health issue in the world as almost 15% of all couples experience infertility and the hormonal imbalance and metabolic dysfunctions occupy the leading places in the problem of reproductive health. Previously viewed as a functional ingredient in its capacity to serve the digestive effects, dietary fiber has now been revealed a powerful regulator of the gut microbiota, hormonal homeostasis, and reproductive outcomes.
Objectives: This systematic review is compiled of existing evidence on the effects of dietary fiber in regulating hormones in the body and fertility effects, by influencing gut health.
Methods: Electronic search through PubMed, Scopus, Web of science and Google scholar (2010-2025). The eligible studies comprised randomized controlled trials (RCTs), cohort, and observational studies concerning the dietary fiber intake, gut microbiota changing, hormonal balance, and fertility results in humans or animals. Narrative reviews, case reports, and studies with no mechanistic connections were the exclusion criteria. Information was distilled on study design, type of fiber, intervention/exposure, and outcomes. Quality of the studies was evaluated according to Cochrane risk-of-bias tool and Newcastle-Ottawa scale.
Findings: Out of the 742 records that were identified, 36 studies had included criteria. Results revealed that dietary fiber improves the diversity of microbes, microbial generation of short-chain fatty acids, and fiber control of the estrobolome, which results in enhanced estrogen metabolism and insulin sensitivity. Fiber intake was found to improve the ovulatory performance of women, decrease androgen surplus in polycystic ovary syndrome (PCOS), and decrease the risk of estrogen-dominant conditions including endometriosis. High-fiber diets were associated with improved testosterone regulation, decreased oxidative stress and semen parameters in men. The anti-inflammatory effects, positive effects on metabolism, and indirect positive effects on fertility were evidenced consistently across studies on fiber.
Conclusion: Dietary fiber has a significant role in the gut-endocrine-reproductive axis, and provides a safe, cost-effective, and sustainable dietary intervention in improving fertility in both sexes. Further studies are needed to determine the best kinds of fibers, doses and microbiota specific approaches to tailor diets