If you're in a long-term relationship, your partner's outlook can have a big impact on how long and how well you live, according to a new study by researchers at Michigan State University.
It turns out looking on the bright side is not only good for our own health and cognition, it's good for our partners as well, says psychology professor William Chopik, the study's co-author.
Optimistic people tend to eat healthier diets, maintain a healthier weight, go to the doctor, be more physically active, earn more and get promoted more often, Chopik tells Colin Peacock.
And whether it's leading by example or by suggestion, they tend to work on keeping their partners healthy, too.
Optimists are usually more supportive to their partners and see them in a positive light, Chopik says.
'You think that your relationship will last longer, you think your partner is maybe more wonderful than they actually are.'
Optimist people often share lifestyle pursuits such as diet and exercise with their partners, he says.
And they tend to be with their own kind.
"Pessimists tend to marry pessimists and optimists marry those who are looking on the bright side, as well.'