(USA TODAY) -- Pediatricians need to work hard to discourage children and teens from drinking alcohol because it damages their developing brains, increases their risk of addiction and can cause accidents that lead to early death, a new policy statement from the American Academy of Pediatrics says.

The minimum drinking age in the USA is 21, but alcohol use is common among teens and young adults, especially college students, says pediatrician Janet Williams, a professor of pediatrics at the University of Texas Health Science Center in San Antonio. She's chairwoman of the academy's committee on substance abuse.

The policy statement, in today's Pediatrics journal, points out that alcohol use among kids and teens:

*Is the major contributor to the leading causes of teen deaths: accidental injury (particularly car accidents), homicide and suicide.

*Increases greatly the chances teens will engage in other risky actions such as substance use, unsafe sex and violent behavior.

*Is more likely to result in binge drinking than alcohol use among adults. That can be fatal. For young people, binge drinking is three or four drinks on one occasion, Williams says.

*Affects developing brains and general health, including possibly harming liver function and ability to fight infections.

The younger people are when they start drinking, the more likely they are to have significant alcohol problems in their lifetime, including abuse and addiction, Williams says.

"Alcohol use is extremely dangerous for youth ... because a remarkable amount of brain development is still occurring at this age," she says. "The parts of the maturing brain that are most impacted by drinking are essential for developing organization skills, emotional regulation, abstract thinking and impulse control."

Pediatricians need to discuss the hazards with their patients, she says, and parents need to set clear rules for their children. They should not give their children alcohol or host teen parties that include alcohol.

"Kids say the biggest reason they don't use alcohol or drugs is that their parents would be disappointed with them if they did," Williams says. Plus, parents need to set a good example, she says. "Drinking in response to every emotion, positive or negative, sets a bad example. Parents need to think of ways to celebrate or problem-solve that don't involve alcohol and that will help their children do the same."

Copyright 2010 USA TODAY, a division of Gannett Co. Inc.