How should you talk to friends and relatives who believe conspiracy theories?

As your uncle passes the roast potatoes, he casually mentions that a coronavirus vaccine will be used to inject microchips into our bodies to track us.

Or maybe it's that point when a friend, after a couple of pints, starts talking about how Covid-19 "doesn't exist". Or when pudding is ruined as a long-lost cousin starts spinning lurid tales about QAnon and elite Satanists eating babies.

The recent rules changes have upended holiday plans for many of us, but you still may find yourself grappling with such situations over the next few days - talking not about legitimate political questions and debates, but outlandish plots and fictions.

So how do you talk to people about conspiracy theories without ruining Christmas?

1: Keep calm

While it's important to confront falsehoods, it's never useful if things end up in a flaming row.

"My number one rule would be to not spoil Christmas," says Mick West, author of Escaping the Rabbit Hole. "An angry, heated conversation will leave everyone feeling rubbish and further cement conspiracy beliefs."

Psychologist Jovan Byford, a lecturer at the Open University, notes that conspiracy theories often have a strong emotional dimension.

"They are not just about right and wrong," he says, "but underpinned by feelings of resentment, anger and indignation over how the world works."

And they've boomed this year, with many searching for grand explanations for the pandemic, American politics, and huge world events.

Catherine from the Isle of Wight understands that better than most. The 38-year-old used to be a big believer in conspiracies about vaccines being used to deliberately harm people. She's since rejected such claims.

"It is extremely important to remain calm at all times," she says. "Whoever you're talking to is often just as passionate as you are about your own beliefs and will defend them to the grave."

And also remember - medical experts say shouting increases the chance of spreading coronavirus. Yet another reason to keep things low-key.

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