Starting college is a big change for teenagers, but a new study published in the journal BMJ Open shows that many struggle with mental health once they get to school. Researchers surveyed almost 1,700 first-year undergraduates at a Canadian university. Six months after starting college, 37 percent had anxiety symptoms and 33 percent experienced depressive symptoms. The students who used illegal drugs had greater odds of developing high levels of anxiety or depression. The good news is that the students who were more socially active tended to have better mental health.