Overview

• Offspring of fathers who began smoking at age 15 or younger showed biological ages roughly 9–12 months older than their chronological ages.
• The gap increased to about 14–15 months among participants who had ever smoked themselves, according to the University of Bergen team.
• Researchers analyzed blood from 892 RHINESSA participants aged 7–50 across Europe and Australia using three epigenetic aging scores.
• Only a small increase appeared when fathers started smoking later in life, with no clear pattern linked to mothers who smoked before pregnancy.
• Scientists propose puberty smoking may alter epigenetic marks in developing sperm, while experts emphasize the observational, early-stage nature of the work, urge replication and stronger teen tobacco prevention, and flag unknown long-term effects of rising youth vaping.