Parents who forbid their daughters to date older boys may be on the right track. A study published on Thursday finds that teenage girls who associate with older boys are more likely to smoke, drink and use drugs.

The survey of 1,000 teens found that friends do influence behavior, or at least reflect behavior, The National Center on Addiction and Substance Abuse at Columbia University said.

“We found a tight connection between teen sexual behavior and dating and teen risk of smoking, drinking and using illegal drugs,” said CASA chairman Joseph Califano, a former U.S. secretary of health, education and welfare.

The survey, which CASA conducts every year, found that the more time a teen spends with a boyfriend or girlfriend, and the more sexually active friends a teen has, the more likely the child will smoke, drink or use illegal drugs.

And girls who date boys two or more years older are much more likely to abuse drugs or alcohol.

Adolescents who spent 25 or more hours a week with a romantic interest were 2.5 times more likely to drink than teens who spent 10 hours or less with a boyfriend or girlfriend.

The teens who spent more time romancing were five times more likely to get drunk - 35 percent of them said they had been drunk compared to 7 percent of the teens who spent less time dating.

The study found that 58 percent of girls who had boyfriends two years or more older drank alcohol, compared to 25 percent of the girls who dated boys their own age or not at all.

Fifty percent of the girls who went for older boys or men smoked marijuana, compared to 8 percent of the other girls, and 65 percent of these girls who preferred to date someone older than themselves smoked, compared to 14 percent girls who stuck to younger boys.

The survey found that 45 percent of the teens said they had been to parties where alcohol was available, 30 percent had been to at least one party where marijuana was available and nine percent where cocaine or Ecstasy was available.

But teens welcome their parents’ guidance on these issues, the survey found.

Asked in the telephone survey what they wished they could “honestly discuss with parents at dinner,” 42 percent said dating and 30 percent said substance abuse. The survey had a margin of error of three points.