Burnout is often described as a problem of work overload or poor work-life balance. But if it were only about hours worked, then everyone working long shifts would burn out. We know that’s not true.

Trying to live a selfless life is a fast track to physical and emotional illness — and often to strained or broken relationships. Living a selfless life leads to emotional isolation and loneliness, the kind research equates to smoking 15 cigarettes a day. That level of loneliness breaks people down.