A sore throat can be a sign of all kinds of medical maladies.

You might have caught a cold from your co-workers or just cheered too loudly at that big game last night.  But if it feels like there's an irritating lump in your throat, there might actually be something stuck back there - a whitish, yellowish tonsil stone.

These hard globs come from the food bits, dead cells and other junk in your mouth. But even though they might be a little weird and uncomfortable and gross, there not really dangerous.

Your tonsils are part of your lymphatic system. They work with a bunch of other tissues to get rid of waste and fight off infection. There are actually three different groups of tonsils, but tonsil stones mostly show up in the palatine tonsils.

The palatine tonsils are those two squishy patches at the back of your throat that you can see in the mirror if you open your mouth wide enough. The palatine tonsils are full of tonsillar crypts, which are deep folds of tissue that are designed to lure in bacteria and maximize the amount of tissue that those bacteria touch. That way, lots of immune cells can be exposed to potential pathogens and start to build up a targeted immune response with antibodies to fight them off. 

Unfortunately, when you have cosy crevices for bacteria, sometimes they get a little too comfortable... These crypts can collect dead cells, extra mucus and food debris or other particles that somehow end up in your mouth - which provide a delicious breeding ground for lots of different microbes. 

After a film of bacteria forms, these goopy lumps can start to calcify, becoming hard structures made of calcium and other minerals. The solid lumps that form are called tonsil stones or tonsilloliths. Tonsil stones can vary in size from a couple millimeters to a couple centimeters.

Sometimes people just swallow them or sometimes they stick around and can irritate your throat. Some bacteria that have been found on tonsil stones produce lots of sulfur compounds, which might cause bad breath. But that's usually the worst of it. 

It's really rare for tonsil stones to get big enough to be dangerous and make swallowing painful or difficult. If you wanna get rid of them, you can try to pop them out using a brush or some gargling. Or you can go to an ear, throat and nose doctor for expert help.

Tonsil removing surgery is a last resort, if these chunks form all the time or become severely irritating. Other than surgery, there's not much you can do to stop tonsil stones from forming. They're just one of those weird things your body does sometimes. But, at least they're not dangerous.

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