Did you know dogs have been shown to smell out bowel cancer?

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By The Gut Health Doctor Team

Dr Megan Rossi in a lab looking through a microscope

More than a (wo)man’s best friend, a landmark study showed a trained sniffer dog could identify patients who had cancer vs those that didn’t with high accuracy, just from their breath even for early-stage cancers. They could also detect the cancer scent from people’s poop.


Our breath contains a bunch of chemicals, many that are produced in our large intestine by our gut bacteria – then they enter our blood and we breathe them out. A dog’s sense of smell is 56 times better than us humans, so they’re well-equipped to sniff out very low concentrations of cancer signs.

What’s more, a pilot study published last month suggested dogs may even be able to sniff out #COVID-19 from saliva with a 94% detection rate. Watch this space!

The tricky part is that dogs do need time beforehand to get the ‘normal’ scent to be able to check for changes – and they may not always be able to tell the difference between the cancer scent and some other infections, or just a change in diet.

That’s where technology comes in! This concept has been pretty significant as it’s paved the way forward for artificial sniffer machines, which are being used in clinical trials at the moment to check their accuracy in diagnosis compared to more invasive colonoscopies (where you have a camera up your back end, definitely not as pleasant as a dog sniffer..).

At King’s College London, we actually used a ‘sniffer’ machine for poop samples in our study looking at IBS and diet.

As for Pistachio, I’m not sure his little nose would be quite up to it…


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