The seventh annual Digital News Report showed a fall in the number of people using Facebook as a news source, while the young audiences are more likely to use WhatsApp, Instagram and Snapchat for news.
The research, by the Reuters Institute for the Study of Journalism, at the University of Oxford, was based on a YouGov online survey of 74,000 people in 37 countries.
Report lead author Nic Newman said: "We're seeing many switching their focus to more personal, private spaces like messaging apps for sharing and discussing news.
"This gives people more control over where and how they engage, but also potentially makes public debate and news distribution even more fragmented and opaque."
The number of those surveyed who accessed news via WhatsApp had more than doubled in two years, to 16 per cent.
The number of people using Facebook for news had fallen overall in the US by 10 per cent in the last two years. The fall was highest among 18-24 year-olds and the 45-54 age group.
The report said the decline in the use of Facebook for news was due to privacy concerns and the harsh opinions that can arise from debate.
Facebook's decision to change its algorithms to show posts of friends rather than external news sites was also a contributing factor.
It should be noted that WhatsApp is owned by Facebook.
Fake news is still a concern, with 54 per cent of those surveyed saying they were worried about the issue.
Trust in news overall stood at 44 per cent - but only 34 per cent of those surveyed said they trusted news they found via search, and just 23 per cent trusted news on social networks.
Prof Rasmus Kleis Nielsen, one of the writers of the report, said: "The frequent use of the dangerous and misleading term 'fake news' resonates with a long-standing crisis of confidence, where much of the public does not feel it can trust the news, especially in countries with highly polarised politics and where many media are vulnerable to undue economic or political influence."
The report also found that users are still reluctant to pay for online news content.