A father’s exposure to secondhand smoke during his own childhood may significantly diminish the lung health of his children, even generations later, according to research published September 2, 2025. The findings suggest that epigenetic changes caused by early-life smoke exposure can be passed down, predisposing offspring to respiratory issues.
The study underscores the lasting impact of environmental toxins and introduces the possibility of inherited vulnerability to lung disease beyond genetic predisposition. This has implications for millions, as historical rates of smoking were substantially higher, meaning a large proportion of the population may carry these epigenetic markers. Researchers are now investigating potential interventions to mitigate these inherited effects and improve long-term respiratory outcomes for future generations.
The research, detailed in a report released September 2, 2025, indicates that paternal exposure to passive smoke alters DNA methylation patterns in sperm, affecting genes crucial for lung advancement and function. These changes aren’t alterations to the DNA sequence itself, but rather modifications that influence how genes are expressed. Offspring of fathers exposed to smoke exhibited reduced lung capacity and increased susceptibility to respiratory infections in laboratory models.
“we observed a clear correlation between the father’s childhood smoke exposure and compromised lung health in their offspring,” stated a researcher involved in the study. “This suggests that the effects of secondhand smoke can extend far beyond the initially exposed individual.”
The findings highlight the importance of smoke-free environments, not only for current generations but also for those yet to be born. Further research is planned to determine the extent to which these epigenetic changes can be reversed or prevented.
