Overview
- Smoking 2–5 cigarettes per day was linked to about a 50% higher risk of cardiovascular disease and a 60% higher risk of death from any cause versus never smokers.
- Heavier use showed a dose–response: 11–15 cigarettes daily was associated with an 84% higher cardiovascular risk and more than double the risk of death.
- Risk dropped most in the first 10 years after quitting, yet former smokers may need roughly 31–40 years for risk to approach that of people who never smoked.
- The PLOS Medicine analysis harmonized 22 cohorts, tracking more than 300,000 adults for up to about 20 years and documenting over 125,000 deaths and 54,000 cardiovascular events; lifetime smoking was defined as at least 100 cigarettes.
- Authors noted limits including baseline self-reported exposure without updates and a lack of data on other tobacco products or specific non-cardiovascular causes, reinforcing that complete cessation—not simply cutting down—remains the recommended course.