[ZenGum]

I agree with most everything said above. There is probably overdiagnosis, due to complacent doctors, marketing from drug companies and such. Current levels of depression are probably caused by modern lifestyles and the strange sea of chemicals we now live in. There is the assumption that if you're not happy, something is medically wrong, and that it can be fixed with a pill rather than changing your lifestyle.

I want to add:
Is it that antidepressants are overused in the US, or underused elsewhere?
Countries outside the OECD spend their health resources on life-and-death fights - malaria, TB, malnutrition, cholera etc. Anyone who is merely depressed can get along on their own, or fade away and die.

The OECD has much higher suicide rates than poorer countries, despite having much better living conditions. My guess is that anyone in Calcutta who doesn't have a strong will to live has already died of some disease, and has no need to actively end it all.