There’s more to the pledge to have and hold a spouse “in sickness and in health” than you might imagine.

New research indicates that marriage may not always be as beneficial to spouses’ health as some experts have previously concluded.

But on the bright side, married people apparently feel better than their unmarried counterparts. Or at least they are more prone to describe themselves as healthier than they are.

Hui Zheng, lead author of the study at Ohio State University’s Department of Sociology, said marriage is indeed good for the health of many people, but his research shows it doesn’t work for everyone.

If you are already in poor health when you get married, don’t expect any extra benefits. But if you are in good health, you are half as likely to die within three years as an unmarried person in good health.

Dr. Zheng concluded that marriage may help prevent people from getting sick, but it doesn’t help when they are seriously ill.

The fact that married people are more likely to consider themselves healthy might have to do with the social support married people receive from their spouses, Dr. Zheng said.

And it might make it a little less sobering for a couple to pledge faithfulness “to death us do part” knowing they’ll be feeling better along the way.