Dairy intake and semen quality among men attending a fertility clinic

Abstract

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.

Keywords: Infertility; dairy; diet; sperm quality.

Conflict of interest statement

Study funding/competing interest(s): This work was supported by NIH grants R01-ES009718 from NIEHS, P30 DK046200 from NIDDK. MCA and AJG were supported by a Ruth L. Kirschstein National Research Service Award T32 DK 007703-16 from NIDDK.

Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

a Adjusted for age, total energy intake, body mass index, smoking status, abstinence time, previous infertility diagnosis, race, and dietary patterns * P-value