Teenage memories of this often come with a sting: the year you worked out how much longer everything took you than it seemed to take everybody else.

What the research says

A systematic review of young people's own accounts found stigma, embarrassment and difficulty recognising their own symptoms among the main reasons they do not seek help, while encouragement from someone else and a previous good experience made it more likely they would. The private noticing rarely turns into asking on its own. The review pools what young people report as barriers, so it tells you what stops them rather than what would fix it.

Strength of evidence: one line of research. A single study, or a theoretical account.