The cause of any depression are hidden destructive processes in the body. Depression is a signal of the presence of such processes in the body. It can be argued that these destructive processes in varying degrees are present in 99% of the population of all ages. I would call this situation a total epidemic of depression. Damage to human health from depression will increase, if you do not take measures to eliminate this situation. Knowledge of the primary cause of depression makes it possible in practice to solve the problem of treating any depression.