By Natalie Rahhal Acting Us Health Editor
Published: 21:44 GMT, 11 February 2020 | Updated: 00:34 GMT, 12 February 2020
People with happy and optimistic partners will live healthier lives and may even be protected against dementia, suggests a new study.
Researchers say people who spend their lives with a partner who has a sunny outlook had lower risks for Alzheimer's disease, dementia and cognitive decline as the grow old together.
They believe that an optimistic partner may help develop a healthier lifestyle by encouraging things like eating a salad or exercising together.
The study, published in the Journal of Personality, followed more than 4,000 heterosexual couples for up to eight years.
People who were married to optimists fared better cognitively as their lives went on, and the researchers from Michigan State University and Harvard University think it may be because their home environments were healthier and less stressful.
Partners of optimists may be protected from dementia because they are more likely to pick up their significant other's healthy habits and less-stressed attitude
Some say you are what you eat, but others say you are the company you keep.
And that may apply to their habits, too.
'We spend a lot of time with our partners,' remarked Dr William Chopik, an Assistant Professor at Michigan State University.