Mothers who are strict with their teen children also influence the behavior of their teens' friends, a new study suggests.

In fact, the researchers found, the friends were 40 percent less likely to get drunk, 38 percent less likely to binge drink, 39 percent less likely to smoke and 43 percent less likely to smoke marijuana, compared with friends of teens whose mothers were less strict.

"Authoritative parenting -- using a style that balances warmth and communication with appropriate control and supervision -- is not only associated with reduced substance abuse in our own children, but it is also associated with reduced substance abuse in our own children's friends," said lead researcher Holly Shakya, a postdoctoral research fellow with the Gates Foundation Social Networks Project at the University of California, San Diego School of Medicine.

"We also find that some of the effect may be spreading through the adolescent social network -- parents' behaviors affect their children, and that effect spreads to their friends," she added.

The report was published Oct. 8 in the online edition of the Archives of Pediatric and Adolescent Medicine.

Source: U.S. News & World Report
http://health.usnews.com/health-news/news/articles/2012/10/08/strict-moms-influence-kids-friends-study