Being married can make people more prone to depression, a study reveals.
Constant nagging and domestic spats are significant triggers of long-term stress that cannot be outweighed by the positive aspects of wedlock, scientists found.
It can also make husbands and wives far less responsive to positive experiences.
Previous research has shown married people are, in general, happier and healthier than singletons.
But an 11-year study by the University of Wisconsin-Madison poses a question mark over the decades of research linking single life to long-lasting social stress.
The researchers assessed a group of married adults for depression, and gave them questionnaires to rate their stress on a six-point scale.
Nine years later, the questionnaire and depression assessments were repeated.
In year 11, the participants took part in ‘emotional response testing’, measuring how quickly they can recover from a negative experience.
The test, commonly used to assess depression, monitors the frowning muscle – or, the corrugator supercilii.
Participants were shown a mix of 90 negative, neutral and positive photographs.
Those who reported a high level of tension in their marriage were far less responsive to positive images, the study published in the Journal of Psychophysiology concluded.
Professor of Psychology and Psychiatry Richard Davidson said the long-term study sheds light on what makes some people more vulnerable.
He said: ‘This is extraordinarily important because of the cascade of changes that may be associated.
‘This is the signature of an emotional style that reveals vulnerability to depression.’