There's this idea that leading a miserable life will somehow result in an early death, which makes sense. Sad people tend to shrivel like raisins from all the scowling and defeated hunching, and they do say that a broken heart can prove fatal. But no, a study from the medical journal The Lancet finds that contrary to anecdotal reasoning, the crotchety among us will hang on just as long as that guy on your corner always telling you to smile.
The study followed one million middle aged women from 1996 to 2001, tracking them with questionnaires that probed their levels of happiness and relaxation, and also asked them to report maladies like high blood pressure, diabetes, asthma, arthritis and depression or anxiety.
The conclusion was: "In middle-aged women, poor health can cause unhappiness. After allowing for this association and adjusting for potential confounders, happiness and related measures of wellbeing do not appear to have any direct effect on mortality."
Still, the Times points out that self-assessments are unreliable, and that most humans experience emotions with slightly more nuance than "happy" and "unhappy."
“I would have liked to see more discussion of how people translate these complicated feelings into a self-report of happiness,” Baruch Fischhoff, a psychologist at Carnegie Mellon University, told the paper. “Think about everything that’s going on in your life and tell me how happy you are. Happiness is a squishy measure.”
The best line, though, is this: "When the answers were analyzed statistically, unhappiness and stress were not associated with an increased risk of death. It is not clear whether the findings apply to men."