Psychiatrist Frieda Fromm-Reichmann (1889-1957) insisted, back before the idea was popular, that “loneliness [which she described as the 'want of intimacy'] lay at the heart of nearly all mental illness,” Judith Shulevitz writes in the New Republic. These days Fromm-Reichmann’s theory is gaining traction, backed by science. “Loneliness has now been linked with a wide array of bodily ailments as well as the old mental ones,” according to Shulevitz, and it can hasten death as much as smoking.
While there is thought to be a genetic predisposition to loneliness, the world also contributes to this condition. People who feel discriminated against are more likely to feel lonely than those who don’t; African-Americans are lonelier than whites; the less educated are lonelier than the better educated; and the unemployed and retired are lonelier than those with jobs.