It could be statistics - maybe people with depression in the undeveloped world simply die without having the depression diagnosed. Very much this; when you are

It could be statistics - maybe people with depression in the undeveloped world simply die without having the depression diagnosed. Very much this; when you are dealing with starvation and life threatening physical diseases, mental illnesses get short shrift. There may also be a factor that fighting for survival tends to "cure" depression, but that's not a treatment I would advocate. Is it chemical? In some cases, definitely yes. Could we do better as a society, both on being more accepting and supportive but also changing some fundamental things about our culture (more social/economic mobility, more leisure time, less consumerism)? Inarguably, yes. There's no easy solutions.