I have always heard circulation but it started when I was a kid and lived in a cold climate now I am not a kid anymore but still circulating so I don’t think that is it at least for me.
I solved the problem by moving to the tropics, my toes never get cold anymore. Plus my dog is always sleeping on my feet, that helps too. Get your dog to sleep on your feet Zennie, workds great! (or what @MacBean says, hehehe, ga)