Research has shown that people in underdeveloped countries are less depressed. Depression and mental disorders have been cited for being "luxury disorders," which means that in America, we live very comfortable lives. In other countries, however, when you are just trying to survive, you don't have time to be depressed.
Also, there is a factor of how wealthy a person is compared to others. When everyone is operating from a level playing field, and people are equal, there is less prevalence for depression and other disorders. It is not the objective conditions of life that matter, but rather the perception of how you measure up.
Dr. Ron Kessler is a Harvard researcher who was co-director of the World Health Organization’s (WHO) mental health research study initiative. This initiative looked at mental disorders and treatments in 28 countries around the world.
As to why the United States is such a hotspot for mental diseases, Dr. Kessler has said…“that by and large people in less-developed countries are less depressed: After all, he says, when you’re literally trying to survive, who has time for depression? Americans, on the other hand, many of whom lead relatively comfortable lives, blow other nations away in the depression factor, leading some to suggest that depression is a ‘luxury disorder.’ ”