Table 1. Summary of lifestyle factors and mechanisms involved in male infertility.
Lifestyle factors	Proposed mechanisms	References
Obesity	Epigenetic modification of sperm DNA Reduced spermatogenic function Impaired sperm DNA integrity Suppressed HPG axis Increased oxidative stress	Khodamoradi et al. (2020)
Mobile phone use/radiation	Impaired sperm function, motility, and viability Increased sperm DNA fragmentation Reduced sperm anti-oxidative activities	Durairajanayagam (2018)
Diet/Nutrition	Poor semen quality Compromise sperm DNA integrity Increased oxidative stress	Nilsson et al. (2023)
Stress	Impaired sperm function, motility, and viability Suppressed HPG axis Increased oxidative stress	Bhongade et al. (2015)
Recreational Drugs	Proposed mechanisms	References
Tobacco	Impaired spermatogenesis	Nwonuma et al. (2021)
Marijuana	Impaired spermatogenesis and steroidogenesis	Gundersen et al. (2015)
Cannabis	Reduced gonadotropic hormones (LH and FSH) Impaired sperm function, motility, and viability	Nwonuma et al. (2021)
Opioids	Increased sperm DNA fragmentation Reduced spermatogenic function Suppressed HPG axi Impaired acrosomal reaction	Gundersen et al. (2015)
Anabolic steroids	Impaired spermatogenesis and steroidogenesis	McBride & Coward (2016)
Alcohol	Reduced T, estradiol, and SHBG levels Increased oxidative stress Poor semen quality and spermatogenic arrest	Nwonuma et al. (2021)