A large body of research has proven that, when you reinforce gender roles, you do damage to young girls and boys. But a global study published this year shows the depths to which enforcing gender stereotypes harm children. Researchers behind the Journal of Adolescent Health study found that youth subject to strict gender expectations are at an increased risk for mental and physical health problems during and after adolescence. Girls, for example, are at a higher risk for pregnancy, exposure to violence, child marriage, pregnancy, and leaving school early. Boys, on the other hand, are more likely to experience substance abuse, die by suicide, ad have a shorter life span, according to the study's findings.