Parents who supply alcohol for their teenagers’ parties may be encouraging their children to binge drink when no adult is watching, a new study suggests.

The study, which surveyed more than 6,200 U.S. teenagers, also found that parents’ attitudes about drinking influence their children’s behavior in several - sometimes surprising - ways.

Specifically, the researchers found that teens who said they drank with their parents were less likely than others to have binged or used alcohol at all in recent weeks.

The finding is hard to interpret, the study’s lead author told Reuters Health, because the survey did not ask about the context in which this drinking took place; it merely asked kids who they were with the last time they drank alcohol.

And it’s the context that’s likely to be key, according to Dr. Kristie Long Foley of Wake Forest University School of Medicine in Winston-Salem, North Carolina.

For example, she said, when teenagers have wine at dinner with their parents, it may help teach them responsible drinking habits or extinguish some of the “novelty” or “excitement” of drinking.

The study also found signs that strict parenting curbed kids’ drinking as well. Teenagers who said they feared they would have their privileges taken away if they got caught drinking were half as likely to drink as those who thought their parents would not punish them.

What all of this means, according to Foley, is that parents’ influence on teenagers’ drinking is complex, and there may be no “straightforward answers” regarding what works best in preventing underage drinking.

But what does seem clear, she said, is that supplying alcohol for teenagers’ parties is a wrong move. This practice turned out to be the strongest predictor of alcohol use and abuse that the researchers studied.

Foley noted that although many parents who supply alcohol for parties may believe they’re doing something positive - by supervising something they believe their kids would do anyway, with no adult present - the study findings do not bear this out.

Teenagers who said their parents or their friends’ parents had provided alcohol for a party over the past year were twice as likely as their peers to have used alcohol or binged during the previous month.

The study, published in the Journal of Adolescent Health, was based on responses from 6,245 16- to 20-year-olds who took part in a national survey on underage drinking

Overall, nearly three-quarters said they had ever used alcohol, with white and Latino teenagers being more likely than African Americans to say so. About one-quarter said they’d been at party in the past year where parents supplied alcohol, while 14 percent said they were with their parents the last time they drank.

SOURCE: Journal of Adolescent Health, October 2004.