Almost 80 percent of those surveyed happen upon news when they are checking up on friends or sharing photos. Heavy news consumers did not describe Facebook as an important source of news, the study found.
"People go to Facebook to share personal moments - and they discover the news almost incidentally," Amy Mitchell, director of journalism research at Pew, said in a statement.
The survey is the first part of a series of studies that the Pew Research Center in collaboration with the John S. and James L. Knight Foundation are conducting to examine social media and news consumption.
The study said that about two-thirds of all U.S. adults use Facebook. The world's largest social media site displays a stream where people and publishers can share news. Only 4 percent of Facebook news consumers said the platform is the most important way they obtain their news.
Social media is playing an increasingly important role in how people find news. The trend is especially pronounced among young people who prefer to get news through platforms like Twitter or Facebook rather than traditional forms of print or broadcast television.
In an earlier study, Pew found that 34 percent of people aged 18 to 24 consume news through social media compared with 10 percent of adults between the ages of 50 to 64.
The current Pew study found that adults aged 18 to 29 account for a third of Facebook news consumers.
Facebook, Twitter and LinkedIn are all experimenting with ways to aggregate and share news as a way to keep people coming back to their platforms. On Monday, Facebook said that referral traffic to publishers' sites increased 170 percent through the past year.
Facebook users are not discriminating when it comes to the source of news - 70 percent click on news stories because of interest in the topic. Only 20 percent said they read a story based on the news organization.
The survey was conducted August 21 through September 2 among 5,173 U.S. adults including Facebook users.
© Thomson Reuters 2013
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