But according to a new paper, time spent on social media could be associated with a longer life.
The paper, published in the journal PNAS on Monday, asserts that the health effects of active online social lives largely mirror the benefits of busy offline social lives.
“We find that people with more friends online are less likely to die than their disconnected counterparts,” the paper says. “This evidence contradicts assertions that social media have had a net-negative impact on health.”
The study’s methods are detailed at length in the paper, and it was approved by three university and state review boards. But skeptics will note that Facebook itself was closely involved with the paper. William Hobbs, 29, a postdoctoral fellow at Northeastern University, worked at Facebook as a research intern in 2013. Another of the paper’s authors, Moira Burke, worked on it in her capacity as a research scientist at Facebook.
Mr. Hobbs, who conducted the research while he was a doctoral student at the University of California, San Diego, said Facebook had not interfered with the results of the paper.
“We had some things in writing that they couldn’t interfere with the publication of the research no matter what the result was,” he said. He noted, though, that some at the company had been “pretty confident that we were going to find this result.”
A news release sent by a spokeswoman at the University of California, San Diego, drives the point home. “The research confirms what scientists have known for a long time about the offline world: People who have stronger social networks live longer,” the release said.
The study was based on 12 million social media profiles made available to the researchers by Facebook, as well as records from the California Department of Health.
It found that “moderate use” of Facebook was associated with the lowest mortality rate, and that receiving friend requests correlated with reduced mortality, but that sending friend requests did not.
Mr. Hobbs and the paper’s other authors matched records from California’s Department of Public Health with those of California Facebook users, preserving privacy by aggregating the data before analyzing it, the release said. All of the subjects of the study were born from 1945 to 1989.
The paper found that people with large or even average social networks lived longer than people who had very small social networks. It was “a finding consistent with classic studies of offline relationships and longevity,” the release said.
The paper itself acknowledges the study’s “many limitations,” saying that Facebook is unique among social media websites and that its data might not be more broadly applicable. It also points out that its findings represent a correlative relationship as opposed to a causal one: There is no evidence in the paper that using Facebook has any direct effect on a person’s health.
James Fowler, a professor of public health and political science at the University of California, San Diego, and another of the paper’s authors, said he had been surprised that requesting the friendship of others was not found to be associated with a longer life span.
“I had hoped we would find that reaching out to others was associated with better health,” he said.
The new result, Mr. Fowler explained, suggested that researchers who had previously found that people with more friends were healthier might have misunderstood the relationship between sociability and health. It may be, he said, that “the reason why people with more friends are healthier is because healthier people have more friends,” which would suggest that “it may be harder than we thought it was to use social networks to make people healthier.”
Nathan Jurgenson, a sociologist and a researcher for Snapchat, said in an email that the paper provided much evidence against the idea that connections made online exist separately from the “real world,” as if the internet did not exist within the broader universe.
But he pointed out that the study itself, even in providing evidence to support the idea that the internet is not different from “real life,” used language that reinforced the binary view.
“All of the conceptual and linguistic back flips being done here in trying to explain that the virtual world interacts with the real world could be circumvented by instead taking for granted that digital connection is new and different but that it’s also part of this one social reality,” Mr.Jurgenson wrote.
Sociological research into Facebook’s effect on health and happiness has not always been as positive. A study published in the journal PLOS One three years ago found that over a two-week period, the more its subjects used Facebook, the worse they rated their own happiness.
“On the surface, Facebook provides an invaluable resource for fulfilling the basic human need for social connection,” that paper said. “Rather than enhancing well-being, however, these findings suggest that Facebook may undermine it.”
Mr. Fowler said that he had been hounding Facebook to help participate in a health study like the one detailed in the paper since 2010, and that he had hoped its findings would directly inform the evolution of the platform, which he had envisioned as potential boon to public health.
He said his focus when he conceived of the study had been simple: “How can you design this platform to not only make people happier but to make them healthier?”
Mr. Hobbs said he welcomed the scrutiny of those who would note the paper’s close associations with Facebook, saying that the paper constituted a first step.
“At this point, we’re not making any recommendations on how people should use social media,” Mr. Hobbs said. “It’s good to have a long track record of finding these relationships again and again before we start giving recommendations.”