Good news for those of you who hate positive thinking: Researchers say that being unhappy does not increase your chances for illness or premature death. The two are related, they argue, but not the way we think. 

These findings are the result of a 10-year study, published today in The Lancet, involving nearly 720,000 British women between the ages of 50 and 69. Researchers sent out questionnaires asking study participants about their health, their income, their lifestyle, and their emotional wellbeing. Women were asked to rate their happiness, stress, relaxation, and feelings of control over their lives. The respondents completed the same questionnaires every three to five years.

By the end of the study, 4 percent of study participants had died. As previous studies have shown, women who reported being unhappy were more likely to be smokers. They were more likely to be poor, more likely to live alone, and less likely to get regular exercise. 

But once all those factors were controlled for, they were no less likely than their happy counterparts to get sick and die. The researchers found no significant difference in the death rates of happy and unhappy women. Nor did they find an increased death rate in women who reported high levels of stress. Women who were sick were more likely to say that they were stressed, unhappy, not relaxed, and not in control of their lives, but the researchers found no evidence that these factors were actually responsible for the illness. 

All these findings sharply contradict recent trends in research, which have emphasized the role of stress and unhappiness in causing disease.

Members of the research team are quite confident in their conclusions. Speaking in a press release, co-author Sir Richard Peto of the University of Oxford said, “Many still believe that stress or unhappiness can directly cause disease, but they are simply confusing cause and effect. Of course people who are ill tend to be unhappier than those who are well, but [this study] shows that happiness and unhappiness do not themselves have any direct effect on death rates.”

Still, it’s worth noting that happiness is pretty hard to measure. “There is no perfect or generally agreed way to measure happiness or related subjective indices of wellbeing,” the research team admitted in their paper. “Different approaches thus limit comparability between studies.”