The Effect of Nutrients and Dietary Supplements on Sperm Quality Parameters

According to the World Health Organization, infertility is a disease of the reproductive system defined by a failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse.

Infertility, which affects ∼15% of the world’s population, is a global public health issue recognized by the WHO. In the case of male fertility, a recent meta-regression analysis reported a significant worldwide decline in total sperm counts between 1973 and 2011. These data strongly suggest a significant decline in male reproductive health, with crucial implications for human reproduction and perpetuation of the species. Research aimed at revealing the causes and implications of this decline is therefore urgently needed.

Agarwal and colleagues recently suggested that 20–70% of fertility problems are caused by the male partner (Agarwal et al., 2015). This range exhibited large geographical differences, with the highest rates detected in Africa and central/eastern Europe. According to this report, a total of 48.5 million couples worldwide suffer from infertility, suggesting that 15% of couples are affected by fertility problems.

Investigating modifiable lifestyle factors that influence human fertility—such as stress, drug use, smoking, alcohol intake, and diet—is of major clinical and public health importance for understanding the problem. Indeed, several observational studies that explored the associations between dietary patterns, food and nutrient consumption, and sperm quality suggest that adhering to a healthy diet (e.g., the Mediterranean diet) may improve male sperm quality parameters.
One of the causes of male infertility is a reduced or poor sperm quality. Three primary end-points are normally determined to assess sperm quality: sperm concentration, sperm morphology and sperm motility.

In Salas-Huetos et al. (2018) systematic review and meta-analysis, they revealed a significant beneficial effect on total sperm count from supplementation with omega-3 and CoQ10; on sperm concentration from supplementation with selenium, zinc, omega-3, and CoQ10; on sperm motility from supplementation with selenium, zinc, omega-3, CoQ10, and carnitines; and on sperm morphology from supplementation with selenium, omega-3, CoQ10, and carnitines. The review suggests that some dietary supplements may help to modulate male fertility.