Dairy-Derived Bioactive Peptides and the Risk of Prostate Cancer among Iranian Men: A Case-Control Study.

This case-control study aimed to assess the association of dairy-derived digestion-resistant bioactive peptides (BPs) with the risk of prostate cancer (PCa) in a cohort of 50 men with PCa and 99 controls. Dietary, demographic, and anthropometric factors of all participants were assessed. Various types of dairy-derived BPs were determined by an method. High intake of total digestion-resistant BPs, low molecular weight peptides, high molecular weight peptides, phosphorylated residues, disulfide bonds, and antioxidant peptides was not significantly associated with the risk of PCa in the adjusted models (>0.05), while low-fat [odds ratio (OR): 0.19, 95% confidence intervals (CI): 0.05－0.66] and total dairy intake (OR: 0.23, 95% CI: 0.06－0.79) were inversely associated with PCa risk. To the best of our knowledge, this study is the first to report an association between dairy-derived BPs and the risk of PCa and an inverse association with consumption of dairy products in Iranian men likely due to the low intake of this population. Notably, the BP content of dairy products was not significantly associated with PCa risk.