My feet, legs, and hands fall asleep really easily. What is this called, and what might it be a symptom of?

Could be poor circulation. There’s a lot of things that can cause that, including just being predisposed to it.

+1 for @incendiary_dan‘s answer. Other than that, the only things I can suggest are:

Vitamin B-12 deficiency? That can cause tingling or numbness in the limbs.

Very low blood pressure? The lower it is to start, the more easily it can drop to unhealthful levels, possibly affecting one’s extremities.

Anemia/low iron.

@Anemone Well, I can say one thing about that….I have pretty high levels of iron. I had it checked recently.

Something pressing on your spine?

I’m curious about this too—I’m pretty sure it’s because I have poor circulation, but I also know that some people are just predisposed to it. The oddest thing that I ever encountered, though, was when I was at a personal training session at the gym and when my foot fell asleep my trainer had NEVER heard of such a thing!!! How could someone possibly go through 25+ years of life and never have heard of pins and needles?

@hurtntired That is weird.