Jian Huang
Ultra-processed foods (UPFs) are a prominent feature of contemporary diets, but their relevance to male reproductive health remains uncertain. This mini-review synthesizes human evidence linking UPF intake with semen quality, asthenozoospermia, fertility-related outcomes, and reproductive biomarkers. Case-control, cross-sectional, prospective, and short-term controlled feeding studies generally report unfavorable associations, most consistently with lower sperm concentration and impaired motility; findings for morphology, semen volume, and other semen domains are less consistent. Prospective evidence links higher paternal UPF intake with lower fecundability and greater subfertility risk, while a controlled feeding trial indicates short-term changes in reproductive hormones, sperm function, and cardiometabolic markers. Interpretation is limited because UPF intake covaries with overall diet quality and lifestyle, exposure metrics and reproductive endpoints are heterogeneous, samples are modest, and clinically meaningful fertility outcomes are scarce. Current findings are therefore suggestive rather than causal. Larger prospective studies with repeated dietary and reproductive assessment, together with longer controlled trials, are needed to determine whether reducing UPF intake as part of broader dietary improvement benefits male reproductive health.