What causes depression? What we know, don’t know and suspect

When thinking about what causes depression it's important to remember some depression is a normal mood state. Benjamin Combs/Unsplash, CC BY-SA

The term and even diagnosis of “depression” can have different meanings and consequences. Depression can be a normal mood state, a clinical disorder, and even a disease.

If your favourite soccer team loses, you might feel emotionally depressed for a few minutes. If you were a player on the team and you brought about the loss, your state of depression and self-criticism might last much longer. Both can be viewed as normal “depressed mood” states.