Attention-Deficit Hyperactivity Disorder, or ADHD, affects tens of millions of people in the U.S. About one in nine children and one in 16 adults have ADHD. That’s according to an analysis from the nonprofit Children and Adults with Attention-Deficit/Hyperactivity Disorder, or CHADD. As researchers learn more about the brain and its complexities, they’re also gaining new insights into what the condition looks like across different ages, genders, and races. In recent years, more adults — especially women — are being diagnosed than ever before. In this installment of our series “In Good Health,” we focus on ADHD – from symptoms, to diagnoses, to treatments.