A new report by Statistics Canada says the average age for teenagers to take their first drink is just over 12, with a very slight difference between boys and girls.

Glue-sniffing begins at an average age of just over 12, while using other drugs including marijuana begins before teens turn 14.

But, the report says, it is the behaviour of friends that is the most influential factor in whether adolescents use drugs and alcohol.

Two-thirds of adolescents who reported that all or most of their friends were using alcohol had themselves been drunk at least once, the study found. Of those who had few or no friends using alcohol, eight per cent reported having been drunk.

The study found similar results for smoking marijuana. Four-fifths had smoked marijuana if most or all of their friends had smoked. Seven per cent had tried the drug if their friends had not.

Despite the apparent statistical link, the report concedes that children may simply be hanging out together because of similar attitudes toward drugs and alcohol – a case of "birds of a feather flock together."

Previous analysis has shown a link between parental substance use and adolescent use, but in this study, peer behaviour was more prominent.

The study did find there are indications that certain parenting activities such as "nagging, inconsistent enforcement of rules, threats and anger" could lead to substance abuse.

The report adds that parents acting that way don't necessarily cause substance abuse in children. A parent's way of dealing with a child could have become hostile due to his or her drug and alcohol use, the report notes.

Jeff Karabanow, a social worker at Dalhousie University in Halifax, said the results are a reminder to parents to talk to their teenagers.

"As long as parents are open to discussing these issues with their children, I mean that's the best we can do," said Karabanow.

The rate of substance abuse nearly doubled for children in step-parenting situations, as well as for those who did poorly in school.