Blowing noseSkye Gould/Tech Insider

Very few people talk about these things, but let's break that taboo.

About nine months ago, after I got a very bad cold, the mucus in my nose turned green. This was normal, I thought, because I was sick.

But now, nearly a year later, it's still green. It's still green! After a year!

After realizing I'd also been coming down with many more colds than usual, I finally went to a doctor. He put a scope up my nose and concluded that I'd been suffering from a chronic, low-grade sinus infection that whole time. And I didn't even know it.

The mucus in your nose serves many functions. Its color can tell you and your doctor a lot about what's going on in your body — especially when it's been an abnormal shade for a long time.

Here are a few of those things, sourced mainly from this Cleveland Clinic infographic and the Centers for Disease Control. You should know, however, that snot color is not enough to diagnose anything outright. Still, it offers a unique glimpse into your body's strange ways of telling you that something's up.

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