Wedlock tends to stave off dementia, according to a new Michigan State University study. Analyzing 14 years of data on 15,000 people older than 52, researchers found those in all unmarried groups—cohabiting, divorced, separated, widowed and never married—had significantly higher odds of developing dementia than their married counterparts. The differences were most acute for those divorced, separated or widowed—about twice as prone as married people to develop dementia, with the men faring worse cognitively than the women.