Conspiracy theories are hardly a modern affliction: think of the JFK assassination or the long history of UFO sightings. Yet the internet is often said to have ushered in a 'post-truth' era, with social media, in particular, allowing for the spread of viral misinformation.

Whether or not that's actually true is another matter, and it's a serious one that merits consideration.

To date, there is little systematic evidence to suggest that conspiracy theories are increasing in popularity, despite what many journalists, scholars, and policymakers say.

That's the conclusion of a new series of surveys conducted in the United States and six European countries. The new study instead suggests conspiracy theories are a "more persistent and ubiquitous feature of human society" than commonly thought.

But it's not all bad news. The good news is that it doesn't look like social media or online news outlets are necessarily to blame. While they might spread misinformation, and dangerously so, it seems conspiracy theories are not necessarily attracting more believers than they did in decades gone by.

When researchers compared national surveys on both recent and old conspiracy theories, they found no evidence of increasing beliefs in the modern age.

"Despite popular claims about America slipping down the conspiracy theory rabbit hole into a state of post-truth, we do not find that conspiracism has increased over time," says political scientist Adam Enders from the University of Louisville.

"We examine beliefs in dozens of specific conspiracy theories, perceptions of who is likely to be involved in conspiracy theories, and the general predisposition to interpret events and circumstances as the product of conspiracy theories – in no case do we observe an average increase in conspiracy beliefs."

The first set of surveys compared the American public's belief in conspiracies that were less than a year old, like those regarding COVID-19, versus older conspiracies, like those regarding the Pearl Harbor attack.

When it came to five conspiracies regarding COVID-19, researchers found no evidence of increased beliefs in repeated polls between March 2020, June of the same year, and May 2021.

In fact, several of these COVID-19 conspiracies fell out of popularity over time, like the one that argues Bill Gates is behind the global pandemic.

QAnon is another recent conspiracy theory explored by researchers. In August of 2019, 5 percent of respondents in the US said they believed in QAnon.

That might seem relatively low, but when researchers asked less specific questions, up to 50 percent of American believed aspects of the QAnon conspiracy, like the existence of a 'deep state' or elite sex traffickers.

Interestingly enough, these beliefs remained relatively constant throughout the global pandemic and the 2020 US election cycle.

"While the baseline levels of belief in these theories are normatively troubling, in no instance do we observe evidence of significant over time increases," the authors write.

Of the 46 conspiracy theory beliefs examined by researchers, only seven increased in popularity over time in the US, and none of them involved COVID-19 or QAnon.

The findings suggest that 'newer' conspiracy theories are not attracting more believers than they did in the past, even with the internet acting as a megaphone for misinformation.

When surveys in the US were compared to those from Europe, polls conducted in 2016 and 2018 once again found no evidence that conspiratorial beliefs – in extraterrestrial cover-ups, for instance – increased over time.

These findings align with other recent studies, backing up the new study's determination that the internet is "less hospitable to conspiracy theories than is often assumed".

"Our findings also comport with studies demonstrating that online conspiracy theories, 'infodemics,' and echo chambers may not be as widespread or influential as sometimes claimed, and are reflective of studies arguing that people are not engaging with or sharing conspiracy theories online as much as sometimes assumed," the authors of the new study write.

Instead, the results suggest that increased public awareness of conspiracy theories created an illusion that conspiracy theories are becoming a bigger problem. In reality, the popularity of these beliefs remained relatively constant over time.

If that's the case, then the idea of a 'post-truth' world has to be reexamined. Combating misinformation is vital to both democracy and public health, but unless we know where this fake news is coming from and how it convinces people, there's not much we can do to change minds.

Blaming social media might feel right, but unless we gather evidence to support that explanation, it's just as baseless as a conspiracy theory itself.

The study was published in PLOS One.