Happiness has no direct effect on women’s mortality despite a widespread belief that being unhappy and stressed can cause ill-health, according to a major new study.
The research, carried out as part of the UK Million Women Study and published on Thursday in The Lancet medical journal, found that, while life-threatening poor health causes unhappiness, the overall death rate among women who were unhappy was the same as among those who were generally happy.
“Illness makes you unhappy, but unhappiness itself doesn’t make you ill,” said Dr Bette Liu, lead author of the research. “We found no direct effect of unhappiness or stress on mortality, even in a 10-year study of a million women.”
The researchers followed the health of 700,000 women – with an average age of 59 years – over 10 years with 30,000 of the participants dying during that time. The report found that after taking account of previous ill health, smoking, and other lifestyle and socio-economic factors, unhappiness itself was not associated with increased mortality.
Deprivation
Unhappiness is associated with deprivation, smoking, lack of exercise and not living with a partner, while women surveyed who were already in poor health tended to say they were unhappy, stressed, not in control and not relaxed.
Three years after joining the study, the women were sent a questionnaire asking them to rate their own health, happiness, stress, feelings of control and whether they felt relaxed. Five out of six said they were generally happy with one in six generally unhappy.
Given the number of people surveyed, the report’s authors say its results rule out unhappiness as being a direct cause of any material increase in mortality.
However, they highlighted the lack of research into the association of happiness with cognitive decline and dementia, saying that happiness is associated with healthy lifestyle choices which can protect people from developing dementia.
They also called for more research into happiness during childhood which could have important consequences on health later in life.
Previous reports which have found that happiness, being in control, feeling relaxed or general wellbeing can reduce mortality do not allow for the strong effects of ill health on unhappiness and stress, according to the study.
“Many still believe that stress or unhappiness can directly cause disease, but they are simply confusing cause and effect,” said report co-author Sir Richard Peto. “Of course people who are ill tend to be unhappier than those who are well, but the UK Million Women Study shows that happiness and unhappiness do not themselves have any direct effect on death rates.”
