Unfair teachers can cause headaches in adolescents, according to an Italian study published in the journal Headache. About 40% of 4,386 adolescents suffered from headaches at least once a week. Girls were more likely to have headaches and kids who had better classmate social support had fewer headaches. The researchers used an established “Teacher and Classmate Support Scale” to measure these effects and also took into account other factors that could have skewed the data. They looked at family and friend empowerment, bullying, school achievement, and trust in people, and none of those factors seemed to play a role in causing headaches. Psychological stress worsens headaches in adults too, but it seems to have a more pronounced effect in adolescents.