Healthy and unhealthy dietary patterns and sperm quality from the Led-Fertyl study

Dietary patterns may affect sperm quality, but the scientific evidence is limited.

To evaluate the association between adherence to different a-priori dietary patterns and sperm quality parameters in healthy reproductive-age men.

A cross-sectional analysis was conducted using data from 200 young men enrolled in the Led-Fertyl study. Tertiles of six a-priori dietary patterns were estimated: four healthy dietary patterns [Mediterranean Diet Adherence Screener (MEDAS), Dietary Approaches to Stop Hypertension (DASH), Healthful Plant-Based Diet Index (hPDI) and EAT-Lancet Score], and two unhealthy dietary patterns [Western Diet and Unhealthful Plant-Based Diet Index (uPDI)]. Sperm quality parameters (count, concentration, vitality, total and progressive motility, and normal morphology) were considered the main outcomes.

Compared with the lowest tertile, participants in the highest MEDAS tertile had higher total sperm count (β = 3.2;95%CI: 1.0, 5.5) and concentration (β = 1.8;95%CI: 0.6, 3.0), and total (β = 8.2;95%CI: 1.3, 15.1) and progressive motility (β = 7.1;95%CI: 0.2, 14.0). Similarly, participants in the highest hPDI tertile had higher total sperm count (β = 3.4;95%CI: 1.4, 5.5) and concentration (β = 1.2;95%CI: 0.0, 2.3) compared with those in the lowest tertile. When these dietary patterns were modelled as continuous variables (for each 1-point increment in the specific score), an inverse association was found between the uPDI and Western and total sperm count [(β = -2.7;95%CI: -4.8, -0.7) and (β = -3.8;95%CI: -5.8, -1.7), respectively] and sperm concentration [(β = -1.2;95%CI: -2.4, -0.1) and (β = -1.7;95%CI: -2.8, -0.5), respectively]. Compared with participants in the lowest tertile, those in the highest uPDI tertile presented higher odds of abnormal sperm concentration (OR: 4.6;95%CI: 1.0, 19.9) and one or more seminogram abnormalities (OR: 2.3;95%CI: 1.1, 5.0).

Our findings suggest that higher adherence to healthy dietary patterns (Mediterranean and healthful plant-based diet) was positively associated with better sperm quality parameters, in contrast, greater adherence to unhealthy dietary patterns was inversely associated.