Think back to your wedding day. Were you a bridezilla, obsessing over every little detail and maybe even becoming depressed over things that didn't go your way? Or perhaps you were more of a Que Sera Sera-bride: Whatever will be, will be, you said. But more importantly: would your friends' memories of your personality back then match up with your own?

If your girls would describe you as more, let's say, emotionally stable, it’s likely that you’ll live a happy, long life, ‘till death do you part, new research from Washington University in St. Louis research suggests. The study, published in the journal Psychological Science, found that your friends’ perception of your personality at a young age is an accurate predictor of longevity.

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“You expect your friends to be inclined to see you in a positive manner, but they also are keen observers of the personality traits that could send you to an early grave,” said Joshua Jackson, PhD, assistant professor of psychology and co-author of the study, in a press release.

Jackson and his fellow researchers analyzed data from a study that began in the 1930s and looked at the personalities of 600 twenty-somethings, most of whom were on their way to the altar. The survey asked the participants' friends, including their bridesmaids and groomsmen, to give extensive ratings of the bride or groom's personality traits. Participants also described themselves.

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Now 75 years later, the researchers figured out when people passed away (or didn't) and used that data to see how their friend’s reports of their personalities corresponded to their lifespans. Their findings showed that the brides whose friends said they were emotionally stable and highly agreeable lived longer, along with the grooms whose best men rated them as more open and conscientious.

Turns out, multiple studies have linked personality traits to lifespan. A multi-study review published in 2011 in the Journal of Aging Research concluded that "there is good evidence that higher level of conscientiousness and lower levels of hostility and Type D or 'distressed' personality are associated with greater longevity."

This new study shows that our friends might be better monitors of our health than we are in some ways. “Our study shows that people are able to observe and rate a friend’s personality accurately enough to predict early mortality decades down the road,” Jackson said in the release. “It suggests that people are able to see important characteristics related to health even when their friends were, for the most part, healthy and many years from death.”

You thought your BFFs knew you well, you just didn't know how well.

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