Around half of U.S. teens have had at least one alcoholic beverage by their senior year of high school.

But health experts say that even a small amount of alcohol can have detrimental effects on the developing brain, like impairing judgment, promoting risky and violent behavior as well as slowing down reaction time.

Doctors at University Hospitals in Ohio, reported that alcohol use can impact the developing frontal lobe, affecting personality and behavior.

Underage drinking can also stunt the growth of the hippocampus, which is a key part of the brain for learning and memory. The earlier a teen begins drinking, the smaller the hippocampus.

According to the Centers for Disease Control and Prevention, teens who drink are more likely to experience everything from to issues with grades to social problems.

So, what can you do to help keep your teen away from the bottle?

Communication is the key.

Studies indicated that the biggest factor influencing a teens decisions about alcohol is knowing their parents’ expectations about underage drinking.

So, talk about it. Express your thoughts, concerns and rules.

Make the rules clear, and monitor your child’s behaviors.

Help your teen stay prepared to handle a situation where their friends might be drinking alcohol.

Make it easy for them to leave a party, or other unsafe situation by making it clear they can text or call at any time for a ride home.

Don’t make jokes about teenage drinking, and make sure your teens understand that underage drinking is not funny, or acceptable.

It’s important to know where your teens are, and who they’re with when they’re away from home. Get to know your teen’s friends and their parents. Go ahead and call those other parents to make sure they’ll be home, and will not allow teens to drink alcohol or use drugs.

Keep track of what alcohol is in your home, and let your teens know that you’re keeping track.

Studies reported that alcohol-related car crashes are the leading cause of death for young people ages 15-24.

Teens who start drinking at an early age, are more like to continue drinking as adults. Those teens are also at a higher risk for dementia, stroke and breast diseases as they age.