Sniffling, sneezing, itchy eyes, asthma flare-ups, and even sleep disruptions. If you're wondering why you're dealing with all the telltale signs of hay fever smack in the middle of December, you might just be grappling with what's commonly known as the Christmas tree syndrome.

In a nutshell, it's a seasonal allergy triggered by the presence of mould in the needles and trunk of the tree. The cosy and humid indoor setting provides the perfect breeding ground for mould, which had already set up camp on the tree back when it was outside.

So, what does this mean in everyday terms? What other exposures are we talking about? In under 3 minutes, we answer your questions!

To listen to the last episodes, you can click here:

Why do we kiss under the mistletoe?

Where did the story of the Grinch come from?

Why do the Japanese eat KFC at Christmas?

A podcast written and realised by Joseph Chance.

In partnership with upday UK.

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