90% of Americans with a substance use disorder began using substances before the age of 18.

All of us want to keep our kids and communities safe from addiction. Prevention is about delaying the onset of first use, whether alcohol, tobacco or marijuana—the most commonly used substances among teens—until the brain has fully matured. The earlier someone starts using substances, the greater their chances of developing a substance use disorder (SUD), and the more severe their illness is likely to be.

The adolescent brain is more vulnerable to alcohol and drugs than the adult brain. The brain continues to develop until the early to mid 20s, with the regions of the brain that control emotional regulation, impulse control and decision-making among the last to develop. This is one reason why adolescents are more likely to engage in risky behaviors and make impulsive decisions, such as trying drugs and alcohol. Early use of alcohol or drugs can disrupt development of the brain in ways that increase the risk of SUD.

Other factors that put an adolescent at risk for developing a SUD besides age of initiation include genetic risk factors and trauma, as well as environmental factors like poverty and exposure to violence.