Background: The fatty acid composition of the sperm membrane changes drastically during spermatogenesis and may be key to its function. Previous data has shown that intake of long chain poly-unsaturated fatty acids can change the fatty acid composition of tissues, including testes and sperm. However, whether these changes in composition translate into changes in semen quality or male reproductive potential is not clear. Materials and Methods: We evaluated the association between intake of fatty acids and semen quality parameters in a cohorts of young, healthy men (the Murcia Young Men Study –MYMS) and a cohort of men in couples presenting for infertility treatment (the EARTH Study). Results: Subfertile men in the with highest intake of saturated fat had 38% lower sperm concentration than men in the lowest intake of saturated fat while intake of omega 3 fatty acids was associated with a higher sperm morphology (Attaman et al. Hum Reprod 2012) and intake of fish, the main dietary source of these fats, was positively related to sperm count (Afeiche et al. J Nutr 2014). In addition, intake of trans fatty acids was inversely related to total sperm count among young healthy men (Chavarro et al. Hum Reprod 2014). Furthermore, sperm membrane fatty acid levels of omega 3 fatty acids were positively related to sperm concentration while sperm membrane levels of trans fatty acids were inversely related to sperm concentration (Chavarro et al. Fertil Steril 2011). Conclusion: Dietary fatty acids may play an important role modulating human spermatogenesis through mechanisms that may involve direct incorporation of fatty acids into the testes and sperm (omega 3 and trans fatty acids) and mechanism independent of direct local incorporation of fatty acids in the testes or sperm (saturated fat). Whether these effects on semen quality translate into effects on fertility remains to be determined.
Materials and methods