Kicking a smoking habit at any age reduces the risk of dying from lung cancer, but smokers who quit as young adults significantly lower their risk of dying from lung and other tobacco-related cancers, new data shows.

In a study involving more than 400,000 Americans, the rate of cancer death among smokers – especially from lung cancer – was three times higher than nonsmokers. But smokers who quit by age 45 reduced their excess risk by 89%. And those who managed to kick the habit by age 35 completely eliminated it.