Research shows nearly 1 in 4 children have tried alcohol by age 13, and the overwhelming majority have experimented by the end of high school. (Christophe Morin/Bloomberg)

Having the "booze talk" with kids before they take their first sip of alcohol is crucial, according to a report released Monday by the American Academy of Pediatrics.

That moment comes earlier than adults might expect, the group said, meaning pediatricians and parents alike should warn children by age 9 about the dangers associated with drinking.

"Surveys indicate that children start to think positively about alcohol between ages 9 and 13 years," a committee of doctors wrote in the report. "The more young people are exposed to alcohol advertising and marketing, the more likely they are to drink, and if they are already drinking, this exposure leads them to drink more. Therefore, it is very important to start talking to children about the dangers of drinking as early as 9 years of age."

[How young is too young to talk about underage drinking?]

Adolescence is a time marked by testing limits and exploring the unexplored, the authors of Monday's study note.

"It is no coincidence that this is the chief period for initiating substance use," they said. "Alcohol is the substance most frequently used by children and adolescents in the United States, and its use in youth is associated with the leading causes of death and serious injury at this age (i.e., motor vehicle accidents, homicides, and suicides)."

Researchers found that 21 percent of young people have tried more than a sip of alcohol by age 13, and nearly 80 percent acknowledged drinking before graduating high school.

In addition, the study noted, 4 out of 5 teenagers said their parents had the biggest influence over when -- and whether -- they decided to drink. A 2013 study, for example, found that parental communication about alcohol before college helped prevent students who didn't drink from becoming heavy drinkers. It also greatly reduced drinking patterns among teenagers who already had begun drinking prior to college.

The AAP physicians particularly underscored research about the dangers of binge drinking, which increases the risk of everything from earlier sexual activity to drunk driving to suicide. The group said just as parents need to talk with their kids about alcohol, pediatricians should be screening every adolescent for alcohol use during office visits and offering advice aimed at preventing substance abuse.

Monday's recommendation matches those of Mothers Against Drunk Driving, which found in a survey earlier this year that, while about one-third of parents begin talking about drinking when their children are high school age, many children already have tried alcohol during their middle school years.

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