Men with younger wives tend to live longer than other men, research has found. But a new analysis by the Max Planck Institute for Demographic Research found that, for women, it's the size of the age gap that affects longevity, not whether she is older or younger than her spouse.
The greater the difference in age, the shorter her life expectancy.
That's not the case for men. A man whose wife is seven to nine years younger has an 11 percent lower chance of dying during a given time period than a man whose wife is the same age.
The results were based on data from nearly 2 million Danish couples.
Women who marry someone seven to nine years younger raise their mortality risk 20 percent, and a researcher had a theory about why.
"One of the few possible explanations is that couples with younger husbands violate social norms and thus suffer from social sanctions," said Sven Drefahl. He said the social pressure could cause a less joyful and more stressful life, reduced health.
He noted, however, that being married still raises longevity for both women and men, when compared to unmarried people.