Phytoestrogens are plant-derived compounds with estrogen-like activity, found in foods such as soy, flaxseed, and red clover. Their use in the context of benign prostatic hyperplasia (BPH) is based on their potential to modulate hormonal pathways involved in prostate growth. Some laboratory and animal studies have shown that phytoestrogens, particularly isoflavones, may inhibit the proliferation of prostate cells and reduce the expression of enzymes involved in androgen metabolism, such as 5-alpha reductase. Additionally, epidemiological data suggest that populations with higher dietary intake of phytoestrogens (notably East Asian populations) have lower rates of BPH, although many confounding factors exist. Small-scale human studies and clinical trials have explored the impact of phytoestrogen supplementation on BPH symptoms, with mixed results. Some trials report modest improvements in urinary symptoms and prostate volume, but meta-analyses and systematic reviews generally conclude that the evidence is limited and not robust. Major clinical guidelines do not currently recommend phytoestrogens as a primary or adjunctive therapy for BPH due to insufficient high-quality data. In summary, while there is some scientific rationale and preliminary data to suggest potential benefit, the overall evidence supporting phytoestrogens for BPH is weak (rated 2/5), and more rigorous clinical trials are needed to establish efficacy and safety.