Dairy intake and semen quality among men attending a fertility clinic

Objective: To examine the relationship between dairy food intake and semen parameters. Design: Longitudinal study. Setting: Academic medical center fertility clinic. Patient(s): One hundred fifty-five men. Intervention(s): None. Main Outcome Measure(s): Total sperm count, sperm concentration, progressive motility, morphology, and semen volume. Result(s): Low-fat dairy intake was positively related to sperm concentration and progressive motility. On average, men in the highest quartile of intake (1.22-3.54 servings/d) had 33% (95% confidence interval [CI] 1, 55) higher sperm concentration and 9.3 percentage units (95% CI 1.4, 17.2) higher sperm motility than men in the lowest quartile of intake (<= 0.28 servings/d). These associations were primarily explained by intake of low-fat milk. The corresponding results for low-fat milk were 30% (95% CI 1, 51) higher sperm concentration and 8.7 percentage units (95% CI 3.0, 14.4) higher sperm motility. Cheese intake was associated with lower sperm concentration among ever-smokers. In this group, men in the highest tertile of intake (0.82-2.43 servings/d) had 53.2% (95% CI 9.7, 75.7) lower sperm concentration than men in the lowest tertile of cheese intake (<0.43 servings/d). Conclusion(s): Our findings suggest that low-fat dairy intake, particularly low-fat milk, is related to higher sperm concentration and progressive motility, whereas cheese intake is related to lower sperm concentration among past or current smokers. (C) 2014 by American Society for Reproductive Medicine.