It’s common for people to harm themselves in some way, by smoking, drinking, eating too much or not enough, exercising too much, or working too hard. But for some people, self-harm is more severe and can become a problem.
Here’s a helpful video about self-harm produced by Mind, a mental health charity.
Whether the person tells you, or you think someone might be hurting themself, it can be difficult to know how best to approach the situation.