Now firstly before I start I understand some people feel a little like vomiting when they think about snot so please feel free to exchange the term “snot” for your preferred term be it “mucous”, “phlegm”, “boogers”, or “bats in the cave”.
Snot never seems like a nice helpful thing. We all know those little kids that have it streaming out of their nostrils like giant slugs crawling toward their mouth. And then when they sneeze and say”I think I need a tissue” as they pull their hand away to a sticky tenacious rope of mucous strung between their hand and nose (and you silently think “No sh#t Sherlock!” as you hand them a tissue).
No snot is not one of the more endearing features of our body.
But it is very helpful and has a purpose even if you only really notice it when it changes colour or consistency or amount.
Snot is mucous and mucous covers many organs and lines many cavities. For example, it keeps your airways moist, traps harmful bacteria that you inadvertently inhale through your nose, protects the stomach lining against acid, and keeps places that should be moist, moist - like sinuses, stomachs, lungs and vaginas.
More importantly it is the first line of defence against viruses and bacteria because it contains antibodies that help fight infection.
So mucous is really quite advantageous … until there is a bit too much.
When you get sick, you make more…sometimes a lot more! And it can drain out more slowly because your nose and sinuses are inflamed and this narrows the passages. So not only do you become snot city but it is a traffic jam of congestion as it struggles to leave your cavities.
But what does snot tell you about your health? What does the colour and the amount mean?
When you are sick your body produces an enormous amount of mucous to trap allergens and bacteria and anything else that shouldn’t be there. At the start of an infection your body makes neutrophils, a type of white blood cell. They are like the first responders at the site and trap then destroy the invader. Once they have done their job they die and get trapped in the mucous. Neutrophils have a chemical inside them that turns your snot green, yellow or any shade in between. So yellow or green snot doesn’t specifically indicate whether the infection is viral or bacterial or even that it is still there. It simply indicates your white blood cells have a mounted an immune response and these cells changed the colour of your mucous.
Mucous is like a graveyard for dead white blood cells!
Having yellow or green snot doesn’t necessarily mean you need antibiotics. What determines that is more how you are feeling and whether you are getting better and improving or getting worse.
What about the amount of snot? I mean we have all had that cold where we blocked up, couldn’t breathe and felt that if someone squeezed us tightly we may explode showering mucous on those in a 20 metre radius.
Some of us are just mucous producers and produce more than normal. Some of us are winter produces and produce lots to counteract heating and the dry cold. Some viral infections create so much snot you spend your days with tissues stuffed up to stem the flow. Some of us can’t eat spicy food without mucous flowing freely from our noses. And some of us just need to step outside in the cold weather and our nose leaks and our eyes join in.
Just like the colour of your snot isn't a great diagnostic tool, the amount of snot seems to be more about how you are feeling, what's normal for you as a mucous producer and whether you are improving.
So here is a simple directory of snot:
Clear - Normal, thin, watery and enough to keep those passages from drying out. It is a good one.
Cloudy or white - Could be an infection brewing or it could be you are dehydrated and the flow of mucous is slowing down.
Yellow or Green - You have an infection or had one but remember those white blood cells have already mounted a response, died and discoloured your mucous.
Pink/Red or Brown - Damage or trauma like you blew your nose to hard, picked a winner or your nose has dried out (common in winter).
Black - This could be a problem unless it is from pollution but might be worth getting it checked out.
Whatever hue your snot may present, celebrate your mucous for keeping the parts that need to be moist moist and its infection fighting abilities.
And remember, don’t judge a booger by its colour.
For those who are into a bit of mucophagy (that is, mucous feeders or nose pickers), eating those boogers won’t kill you but it is unlikely to be beneficial for you either. Choose your own path there.