Who believes in conspiracy theories, and why? That is the question asked in a five-year study at Cambridge University, which commissioned three surveys from YouGov (2015, 2016 and 2018) to get a sense of the phenomenon.

It turns that out 60% of British people believe in at least one of the 10 conspiracy theories we put to them. So, for instance, 8% think humans have made contact with aliens at Roswell but the US government is hiding it from us; 7% believe that global warming is a hoax invented to deceive people; and 10% agree that the truth about the harmful effects of vaccines is being deliberately hidden from the public.

On all these counts the British average is lower than its European or American counterpart, but there are two views in particular where it scores higher, and both are related to immigration. “The government is deliberately hiding the truth about how many immigrants really live in this country”, believe 30% of respondents. Muslim immigration is particularly singled out, with 18% agreeing that it is “part of a bigger plan to make Muslims a majority of this country’s population”.

Our research reveals that belief in conspiracy theories is linked to two things: a sense of threat, and a feeling of being excluded from power. The sense of threat comes from fears about mass migration: remember Nigel Farage’s “breaking point” poster, which played on fears of Syrian refugees swamping our shores? Being excluded from power comes from a feeling of not being listened to by politicians.

The most believed statement in our latest survey was the claim that “even though we live in what’s called a democracy, a few people will always run things in this country anyway” (44%). It is debatable whether that is a conspiracy theory or not – it might just be a true reflection of reality – but combined with the extreme levels of distrust in government (76% distrust ministers) and company bosses (74%), it shows how people feel they are not being heard.

Conspiracy theories allow people to regain a sense of control over their lives: they offer a reasoning for all the crazy and inexplicable things that happen in the world, often by seeing them as the secret machinations of a hidden and extremely powerful group of people who control everything (14% believe that “regardless of who is officially in charge of governments and other organisations, there is a single group of people who secretly control events and rule the world together”).

‘Studies show that those with higher educational achievements are less prone to believing conspiracy theories.’ Composite: Alamy/Reuters/Linda Nylind/PA

This is why the official leave slogan – “Take back control” – sounded so appealing to those susceptible to believing in conspiracy theories; and we now know that leave voters are much more likely to believe in conspiracy theories (71%) than remainers (49%). The latest conspiracy theory coming out of the ultra-Brexiters’ camp is that the reason Graham Brady has not revealed the 48 letters needed to trigger a confidence vote in Theresa May is because he was recently knighted.

With that in mind, here are five suggestions of how conspiracy theories might be tackled:

1 Talk to friends who believe in conspiracy theories



Although mistrust in politicians and other leaders is at an all-time high, trust among friends (87%) and family members (89%) remains rock solid. This can be a double-edged sword: if conspiracy theorists are friends with other conspiracy theorists, then that’s likely to be mutually reinforcing. But conspiracy theorists will also listen to their friends and family who are not. So if you have a friend who starts sayings things about how the CIA was behind 9/11, try talking to them. You never know, they might come round to thinking it was al-Qaida who hijacked the planes, after all.

2 Listen to academics



Sadly journalists (distrusted by 77% of respondents) are no better trusted than government ministers or company bosses. Academics, however, fare better and retain the trust of 64% of the public. So academics should engage more with the public: Cas Mudde for instance, an expert on populism, who worked on a new Guardian series about “the new populism”. Consider this column my own attempt to do so, too.

3 Educate yourself



Studies show that those with higher educational achievements are less prone to believing conspiracy theories. The implication here is there should be more investment in education, which of course would be welcome. But compulsory courses on online education – learning to tell fake news from real for instance – should be considered, too.

4 Regulate the technology



By asking questions about social media consumption, our latest poll confirms what has been suspected for a while: social media encourages conspiracy theories. Not all, mind you: Facebook encourages conspiracy theories, but Twitter mitigates against them. It turns out YouTube is the worst offender: those who get their news from the video platform are much more likely to believe conspiracy theories. So far most of these new technologies have been left to regulate themselves, which has led to scandals surrounding the role Facebook might have played in recent elections. Politicians should take a more active role in regulating the spread of fake news and conspiracy theories. Falling that, you’re welcome to delete your various accounts.

5 Politicians, be more responsive



Conspiracy theories spread among those who feel they are not being heard. Politicians have a responsibility to be more responsive to the demands of their citizens: it is true, for example, that the question of this country’s relation to the EU had long been off the table, and fears about immigration often fell on deaf ears. That is not to say they should follow Hillary Clinton in saying immigration into Europe should stop, but a coherent account of what type of immigration this country wants, and why, needs to be offered, alongside a clear vision of what its future relationship with the EU is going to be.

The impact of conspiracy theories on our politics is beyond doubt: from Donald Trump, who launched his political career with the birther movement, which claimed that Barack Obama was born in Kenya, to propaganda during the Brexit campaign that played on fears of a rising tide of immigration coming from Syria. Populist leaders have fuelled conspiracy theories to maintain their grip on power. It is time for responsible politicians to fight back.

• Hugo Drochon teaches politics at the University of Nottingham