… If that doesn’t sound like something straight out of a horror film, I don’t know what does. And yet, a while back, this very story landed on the front page of CNN’s website.

If you’ve ever felt like the food you’re eating has been getting inside your head, it could be because it contains parasites that do just that – moving through your eyes, tissues and, commonly, your brain.

In 2013, the first case of this popped up in the UK when a British man was found to have a tapeworm wriggling through his brain. Dr. Effrossyni Gkrania-Klotsas told CNN the worm had moved from one side of the man’s brain to the other, something very few species of parasite seem to do.

This GIF shows a tapeworm squirming through the man’s brain.

One species, known as Spirometra Erinaceieuropaei, is common to parts of the world like South Korea, Japan, Thailand and China, the latter of which was where the British man had recently visited.

The infection caused by Spirometra Erinaceieuropaei is known as sparganosis and often originates in cats and dogs, where the worm can grow to a terrifying length of 1.5 metres. Put simply, it’s not the sort of thing you’d want to meet in a dark alley on a Friday night.

A smaller – but still terrifying – example of the parasite.

Considering that we don’t (most of us anyway) eat cats and dogs, this parasite wouldn’t be a problem if it only existed in those animals. But sadly, there is another animal that harbors these worms, one the human digestive system is all too familiar with – pigs.

Pork can become infected with tapeworms in a few different ways. The Albertan Agriculture and Forestry Department put together the following helpful diagram detailing the icky process:

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While this diagram highlights the infection process of tapeworms through pigs, only three types of tapeworms can infect a human brain. This occurs when they infiltrate the nervous system.

The results can be pretty horrible.

 

Picture via Discover Magazine

Picture via Discover Magazine

Yup.

This particular image shows the effects of the Taenia Solium, which, like the Spirometra Erinaceieuropaei, inhabits the muscles of pigs.

And just how many people worldwide have been severely affected by tapeworm infiltration of the brain? Dr. Theodore Nash puts the number conservatively at 5 million globally.

That’s not exactly surprising when you consider the diabolical conditions with which pigs are farmed.

I eat meat. But the one meat I’m always a bit hesitant to touch is pork. And after seeing this, I think the bacon chilli cheese poutine sold at my school will be on the backburner for a while.