I'm 18, soon to be 19, and as soon as my body started filling out and maturing (around the age of 11), I have had problems with my feet (just my feet, not my hands at all) turning either a weird red color or a deep purple/blue color randomly, but ALWAYS when I sit down. The tempature has nothing to do with it. It could be a perfectly comfortable temp. and they just turn colors still. And when they do, they are extremely cold to the touch and sometimes become tingly. My weight doesn't seem to effect it either because I have went through spouts of being overweight and actually being underweight and the ugly toes always show up. About a year ago I had surgery and my nurse was so shocked at how dark they were by just laying on the bed before the surgery, she asked me if i could even feel them. I told her it was normal and that they always did that, and she gave me a face and said that it definitely wasn't normal. I've never got around to asking a doctor about it yet because I never had much worry about it until recently, when now sometimes a toe (just one toe) will turn literally white, and go completely numb. I guess what I'm trying to ask is, could this be a circulation problem, and if so, could it be dangerous?