Walnuts Appear to Improve Sperm Quality in Healthy Men

Posted by on Aug 30, 2012
in the category Men's Health

A randomized, parallel, 2-group, dietary intervention trial shows that daily consumption of 75 g of whole-shelled walnuts appears to have positive effects on the vitality, morphology, and motility of sperm in healthy men after 12 weeks.

The healthy dietary habits and essential nutrients for male reproductive fitness are less clear because there is little evidence and studies on the effects of diets on male fertility.

The study was conducted by Wendi A. Robbins, PhD. and colleagues from the University of California, Los Angeles. 120 healthy men between ages of 21 and 35 years were recruited. Approximately 50% of the men were randomly assigned to a control group, the other 50% were assigned to walnut supplementation group for a 12-week trial. The authors revealed that sperm vitality, motility and morphology were significantly improved in the walnut group compared with the control group after 12 weeks. In addition, serum omega-3 and omega-6 fatty acid levels were significantly improved in the walnut group after 12 weeks. The prevalence of sex chromosome disomy and sperm missing a sex chromosome were significantly lower in the walnut group after 12 weeks of supplementation.

Would infertile men benefit from Walnut supplementation?

The authors noted that this study could not clarify whether the effects observed in healthy adults will be applicable to those with fertility issues. "Whether adding walnuts to the diet will go beyond the shifts in sperm parameters as seen in this study to improving birth outcomes for men within fertility clinic populations or in the general population is not yet known and will require further research," the authors write.

However, Dolores Lamb, PhD, the current president of the American Society for Reproductive Medicine, noted that male infertility issue is clearly multifactorial; however, if walnut supplementation may represent a useful strategy for subset of infertile men or men with sperm deficiencies caused by poor viability, poor morphology (for some specific defects), and lowered motilitym, this would be a simple and positive advance.

Biology of Reproduction. Published online August 15, 2012. Full text