It's blood flowing through your ears. Even for how small blood cells are, they flow fast enough at some points to be heard. Since the flow is literally inside your ear, it's close enough to the things in your ear that make you hear, and you hear a small sound similar to flowing water in a wall pipe.

Edit: I hear it when I stand up after sitting cross-legged for a little while. This is the same reason you "hear the ocean" when you put a shell to your ear.

Interesting!! I've always wondered if everyone can hear it, or just me. And thought it was spinal fluid.

This is wild. I hear this at the back of my neck all the time and thought it was brain fluid or something! Haha.

Theoretically, you could put a really small microphone deep in your ear and amplify the sound for others to hear. There's actually a noise there, it's not like tinnitus/hearing loss where there's a ringing. That noise is made by your brain and cannot be heard by others.

But, no, if you stood ear to ear with a buddy they won't hear your blood flowing.

That's so interesting! I have thought about that in the past.

So should I see a doctor if my wife can hear it?

This is so interesting. I don't hear this and thought OP was unique.

> This is the same reason you “hear the ocean” when you put a shell to your ear.

This is incorrect. The noise heard from a shell or cup is ambient sound echoing around inside the container, not blood flow. You can prove this yourself by taking a cup and pushing it against your head so it seals around the edges. The rushing sound will greatly diminish (some will still leak through or be vibrating the cup itself), while of course blood continues to flow in your head.

I would check with your doctor. If it's a whoosing sort of sound of liquid, it could be pulsatile tinitus or sign of high blood pressure or even an issue with the carotid artery. Best to check either way.

I don't have high blood pressure, quite the opposite, it is on the lower side. I most definitely have regular tinnitus, and hearing loss. I do t have a family doctor so it's hard to get smaller things checked.

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