Here’s why you shouldn’t spit out any mucus when you’re ill, according to a doctor

Mucus and phlegm are important parts of the body's immune system and can help trap microbes.

Photo credit: Getty Images

Published: September 15, 2023 at 3:00 pm

People think mucus and phlegm are things you should cough up and get out, because they’re bad for you. But in truth, mucus is the interface between you and the outside world.

It lines the moist surfaces of your nose, sinuses and lungs, and filters out material you breathe in – a bit like flypaper. It’s mostly water, but also contains proteins, sugars and molecules that help the body control harmful germs. Mucus creates a layer of protection between us and the outside world, so it’s not something to get rid of. 

Although we make quite a lot of it all the time, usually you’re unaware of it. It gets pushed to the back of the throat by microscopic hairs called cilia, and you swallow it without noticing. It’s only when you’re ill and it gets produced in excess that you might notice it more.

When you’re unwell, your mucus can become thicker and stickier, but it’s still playing a vital role in trapping bacteria, viruses and cells that are mobilised from your immune system. So, for the most part, leaving the mucus alone is probably for the best. 

Getting rid of it won’t necessarily make you feel better any sooner. But the excess mucus can get a bit annoying. Keeping the air moist, using saline irrigation (using a sinus rinse, which you can buy or make yourself easily at home), gargling with salt water and staying hydrated can all help.

Decongestants from the pharmacy can also help, but decongestant nasal sprays shouldn’t be used for more than a week at a time, as using them for too long can actually make your stuffiness worse.

So, in short – you don’t need to get rid of mucus and it won’t speed up your recovery if you do. But if it makes you feel better, there’s no harm. 

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Asked by: Daniel Grant, Sunderland

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