STUDY: Teens who vape or smoke hookah more likely to use marijuana

LOS ANGELES, California (KTRK) -- A study published in the Journal Pediatrics says that teens who use e-cigarettes and hookahs are more likely to smoke marijuana later in life.

Researchers from the University of Pennsylvania and the University of Southern California surveyed more than 2,600 students at Los Angeles public high schools.

The students, who were 14-years-old and in the ninth grade, were asked if they had ever tried hookahs or e-cigarettes.

Researches did a follow-up survey in the fall of 2015, when the students were 16-years-old and in the 11th grade, and asked them about smoking marijuana.

Research showed that the students who had tried e-cigarettes when they were freshman were three times more likely to have tried marijuana than those who had not tried e-cigarettes.