Study of 9.3 Million Links Smoking Before 20 to Double Heart Attack Risk
Updated
Updated · RBC-Ukraine · May 21
Study of 9.3 Million Links Smoking Before 20 to Double Heart Attack Risk
2 articles · Updated · RBC-Ukraine · May 21
9,295,979 adults tracked for 9.3 years showed people who started smoking before 20 and accumulated more than 20 pack-years faced more than double the heart-attack risk of non-smokers.
Before age 15 emerged as the most dangerous threshold, with the highest mortality and severe cardiovascular-event rates; stroke risk in the early-start, heavy-smoking group was about 80% higher.
Those elevated risks persisted even after adjusting for total smoking exposure, suggesting adolescent blood vessels are uniquely vulnerable to toxin-driven inflammation, blood thickening and early arterial damage.
A separate Johns Hopkins analysis of 22 studies covering 330,000 people found even 2 to 5 cigarettes a day raised heart-failure risk by 50% and all-cause death risk by 60%.
That evidence also showed quitting helps most in the first decade, but former smokers can still carry higher cardiovascular risk than never-smokers even 30 years after their last cigarette.
If smoking just two cigarettes a day is dangerous, what irreversible damage does starting as a teen truly cause?
As teen vaping rises, are strict vape bans accidentally pushing adults back to more lethal cigarettes?
How does a mother's smoking history permanently alter the brain development and health of her unborn child?
Early Smoking Doubles Heart Attack and Stroke Risk: Landmark Study Reveals Lasting Cardiovascular Damage from Adolescent Tobacco Use
Overview
A major 2025 study in Nature/Scientific Reports found that starting to smoke at a young age causes serious and lasting harm to the heart and blood vessels. The research showed that the age when someone begins smoking is a key, independent factor in predicting future heart attacks and strokes. People who start smoking before age 20 have double the risk of these events compared to those who start after 30, and those who begin before 15 face even higher risks. These findings highlight how smoking during the teenage years can lead to severe long-term health problems, even if the person quits later.