New research from Denmark shows that boy toys can be bad for your health.

Researchers have long thought that younger spouses were better for both men and women. But new data gleaned from 2 million couples destroy that theory.

Younger wives are better for men’s health, but younger husbands can be deadly for women.

The numbers show that women who marry men seven to nine years younger increase their mortality risk by 20 per cent. In contrast, men who marry younger women decrease theirs by 11 per cent.

Researchers are at a loss to explain this. They say one possibility is that couples with younger husbands violate social norms and thus suffer from social sanctions. It’s also possible that a younger husband may not enrich a woman’s social life or provide companionship and support late in life. A younger wife, however, appears to do all of those things for her older husband.

But it may not be so good for those young wives. The study, published in the journal Demography says marrying a much older man shortens a woman’s life somewhat.

Apparently, the best choice is to marry a man of exactly the same age. But don’t worry too much. The researchers want to remind us marriage overall still raises life expectancy for women and men compared with people who don’t marry.