Sperm Chromatin and Lifestyle Factors

Excessive sperm DNA fragmentation is linked to male infertility as well as health and behavior issues in the offspring. The three primary mechanisms of sperm DNA damage are impaired spermatogenesis, abortive apoptosis, and oxidative stress. In this chapter, lifestyle factors such as obesity, nutrition, smoking, and alcohol consumption as well as exposure to radiation are all examined as they may increase sperm DNA damage and DNA fragmentation. While the impact of obesity on sperm DNA fragmentation is controversial, a high-fat diet is clearly correlated with loss of sperm DNA integrity, which is contrary to a healthy diet that is high in nuts, vegetables, and fruits. Smoking is only correlated with sperm DNA damage in certain populations, which is explained by the fact that men with certain polymorphisms suffer greater DNA damage from smoking than others. Alcohol and radiation exposures (hospital occupational exposure, X-rays, radiotherapy, and cell phones) are clearly associated with high sperm DNA fragmentation. The mentioned factors may be part of the worldwide observed reduction in semen parameters and sperm function. Identifying these risk factors is important for patient counseling, treatment, and research into alleviating factors.