Facebook is a ubiquitous part of modern living, and now a new study suggests that the social media app may even provide insight into how long you'll live.
Reaching out to others
Researchers found that people who receive and accept the most "friend" requests lived longer. But, the same benefit wasn't seen for people who initiated the friend requests.
"People who are more popular live longer, but we can't say the same of people who are more social – (those who reach out to others more)," said study lead author Will Hobbs. He's a postdoctoral fellow at Northeastern University in Boston.
"We've known for a long time that people with stronger social connections in real life live longer," Hobbs said. "We live in a new reality where many of our social interactions now take place online. We wanted to find out if the same rules apply online."
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But while the study was able to find a link between the number of accepted friend requests and life span, it wasn't designed to prove a cause-and-effect relationship, the authors noted.
For the study, the investigators worked with Facebook, focusing on 12 million users from California who signed up before October 2010 and were born between 1945 and 1989. The researchers also compared these users to California's eligible voter records, and ended up with a Facebook user sample of more than 4 million people.
Other contributing factors
Hobbs and his colleagues also used information from state records to identify 11,995 Facebook users who died between January 2012 and December 2013. The study authors compared the prior Facebook activity of those who had died to the activity of other California users.
The researchers also looked at death rates among similar people in California who didn't use Facebook, and compared them to the Facebook users in California.
The findings showed that people who didn't use Facebook were 12 percent more likely to die each year than those who did. But, Hobbs cautioned against "making too much" of this number because other factors, such as income, might have influenced this finding.
Hobbs added that "the absolute risk of dying any given year was small for the people under 65 that we studied here and especially low for the young people in our sample."
The study authors focused on "friend" requests: When one Facebook user asks another if they'd like to create a connection via the service.
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According to Hobbs, those who accepted an average-to-large number of friendship requests lived longer than those who accepted the fewest. The survival benefit seemed to begin around accepting 47 friend requests, the findings suggested.
More complex dynamics
"The mortality rate for users with the most accepted friendships was about 35 percent lower than those with the least accepted friendships, and those with even average to moderately large friend networks saw similarly low mortality rates compared to the most socially isolated users," Hobbs said.
But the researchers didn't find any connection between life span and initiating those friendship requests compared to receiving them.
Anatoliy Gruzd, an associate professor at Ryerson University in Toronto who studies social media, found the study findings curious. "This suggests that one cannot simply start friending people online to live longer," he said.
"There are more complex dynamics behind this phenomenon," Gruzd said. Perhaps there are differences between the "social influence" of those who seek Facebook friends and those more likely to wait to be asked to connect, he noted.
The study authors also looked for signs – such as posted photos – that Facebook users had lives outside of the online arena.
Read: Facebook habits affect happiness
"Within Facebook, we also found that people who engage in more real-life social activity tend to live longer, the more the better," said study co-author James Fowler. He is a professor of medical genetics and political science at the University of California, San Diego.
So should people change how they use online social networks based on this research?
"It's too early to give a prescription for Facebook," Fowler said. "But our study does suggest we should be doing a lot more research to find out how online social media make us healthy and how they don't."
The study appears in the Proceedings of the National Academy of Sciences.
Hobbs conducted the research while a graduate student at the University of California, San Diego.
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