Only a quarter of Britons trust social media and an overwhelming majority of the public believe social media companies do not do enough to tackle bullying, illegal activities and the spreading of extremist content on their sites, a major survey has found.
Just 24% of respondents to the Edelman Trust Barometer survey said they trusted social media, such as social networks and online forums, compared with 61% who said they trusted traditional media, like newspapers and television.
"It's permeated through to people that there's a lot of embarrassing stuff around on social media now," said Charlie Beckett, director of the Trust, Truth and Technology Commission at the London School of Economics.
"We're in a world where apparently some scary things have happened," he said.
"Brexit and terrorism are worrying people and, broadly speaking, at times of crisis people turn to their most conventional sources of information."
In addition, seven in 10 people believe social media companies do not do enough to stop illegal or unethical behaviour on their platforms, prevent the sharing of extremist content or do enough to prevent bullying.
Most people think companies like Facebook and Twitter are not regulated enough (64%) and lack transparency (63%), just over half (57%) believe social media firms take advantage of users' loneliness and 62% think they are selling people's data without their knowledge.
About one third (34%) do not think social media is a force for good in society.
Facebook, Twitter and other online giants have faced intense criticism from MPs over the way they deal with offensive or extreme content and the Government has warned they face penalties if they refuse to tighten up controls.
Ed Williams, chief executive officer of Edelman UK, said: "After a flood of negative headlines in 2017, it's time these companies sat up and listened.
"The public want action on key issues related to online protection, and to see their concerns addressed through better regulation.
"Failure on their part to act risks further erosion of trust and therefore public support."
And Professor Beckett said social networks and technology firms needed better guidance from policymakers in managing their problems but regulation could cause more harm than good.
"Something has to be done in terms of policy, in a way, to help the platforms," he told the Press Association.
"Because in some ways they don't want to have to deal with it themselves, but they also don't want us to intrude on their algorithms. So I think they would welcome greater clarity."
"Part of the solution is going to be us as individuals and communities," he continued.
"It's people who cause the problems. It's not Facebook or Twitter or Google who publish fake videos or offensive posts, it's us."
The wide-ranging study also found trust in government remains languishing at just 36%, the same as 2017, and 40% believe it abuses its power more than any other pillar of society.
But trust in party leaders Theresa May and Jeremy Corbyn has risen over the last 12 months.
The Prime Minister enjoyed a four-point bounce, 35% to 39%, while the Labour leader scored an extra 13 points, 23% to 36%.
According to the research, 39% of the public back Brexit while 43% are opposed and 12% said they did not care either way.
Distrust in business is fuelled mainly by concerns over high executive pay (58%), tax avoidance (56%) and a lack of transparency in business dealings (45%).
Charles Bowman, Lord Mayor of the City of London and a spokesman for the UK's financial and professional services sector, said: "With trust in business remaining low, today's findings show that business has a lot still to do.
"Improving trust in business is the focus of my mayoral year through the Business of Trust programme."
More than 33,000 respondents took part in 30-minute online interviews from October 28 to November 20 2017.
The survey included 6,200 "informed public respondents" who were aged 25-64, college-educated; a household income in the top quartile for their age in their country; read or watch business/news media at least several times a week; follow public policy issues in the news at least several times a week.