Teens who text 120 times a day or more — and there seems to be a lot of them — are more likely to have had sex or used alcohol and drugs than kids who don't send as many messages, according to provocative new research.

A new study suggests that teens who text more than 120 times a day are more likely to be involved in drugs, alcohol and sex. (iStock)The study's authors aren't suggesting that "hyper-texting" leads to sex, drinking or drugs, but say it's startling to see an apparent link between excessive messaging and that kind of risky behaviour.

The study concludes that a significant number of teens are very susceptible to peer pressure and also have permissive or absent parents, said Dr. Scott Frank, the study's lead author.

"If parents are monitoring their kids' texting and social networking, they're probably monitoring other activities as well," said Frank, an associate professor of epidemiology and biostatistics at Case Western Reserve University School of Medicine in Cleveland, Ohio.

4,200 students surveyed

The study was done at 20 public high schools in the Cleveland area last year, and is based on confidential paper surveys of more than 4,200 students.

Hyper-texting is more common among girls, according to the study. (iStock)It found that about one in five students were hyper-texters and about one in nine are hyper-networkers — those who spend three or more hours a day on Facebook and other social networking websites.

About one in 25 fall into both categories.

Hyper-texting and hyper-networking were more common among girls, minorities, kids whose parents have less education and students from a single-mother household, the study found.

Frank's study is billed as one of the first studies to look at texting and social networking and whether they are linked to actual sexual intercourse or to other risky behaviours.

"This study demonstrates that it's a legitimate question to explore," said Douglas Gentile, who runs the Media Research Lab at Iowa State University.

Hyper-texters more likely to have sex

The study found those who text at least 120 times a day are nearly three-and-a-half times more likely to have had sex than their peers who don't text that much. Hyper-texters were also more likely to have been in a physical fight, binge drink, use illegal drugs or take medication without a prescription.

Compared to the heavy texters, the hyper-networkers were not as likely to have had sex, but more likely to have been involved in other risky behaviours like drinking or fighting.

A Kaiser Family Foundation study found that about half of children aged eight to 18 send text messages on a cellphone in a typical day. The texters estimated they average 118 texts per day. That study also found that only 14 per cent of kids said their parents set rules to limit texting.

Other studies have tied teen texting to risky or lewd behaviour. A Pew Research Center study found that about one-third of 16- and 17-year-olds send texts while driving. And an Associated Press-MTV poll found that about one-quarter of teenagers have "sexted" — shared sexually explicit photos, videos and chat by cellphone or online.