Far from helping them avoid cigarettes, longtime ex-smokers who try vaping are taking a big risk that they'll relapse, a new study finds.

People who've spent a year off smokes are nearly four times more likely to start lighting up again if they experiment with vaping, compared with those who don't, according to findings [...]

"Even sampling nicotine can prime the brain for wanting more," said lead researcher Dr. Wilson Compton, deputy director of the U.S. National Institute on Drug Abuse in Bethesda, Md. "Once you're off of nicotine completely, the safest approach is to stay off of it 100%."