A recent scientific study revealed a concerning link between fathers smoking during adolescence and accelerated aging in their children later in life, according to Medical Express.

Researchers at the European Respiratory Society conference in Amsterdam found that children whose fathers smoked during puberty show signs of biological aging faster than their actual age.

The study, led by Dr. Juan Pablo Lopez-Servantes from the University of Bergen in Norway, showed that this accelerated aging is especially evident among children of fathers who started smoking before the age of fifteen, with these children being biologically older by between nine months and a full year compared to their chronological age. This gap widens to 14 to 15 months among children who also smoke themselves.

Researchers explain this intriguing phenomenon by noting that smoking during puberty—a critical period when reproductive cells develop—may cause genetic changes in boys’ sperm. These environmentally linked genetic modifications do not alter the DNA sequence itself but affect how genes function and can be passed down through generations.