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At this point your endangered skin–your ears and nose, or maybe your toes–will turn a bright red, and you’ll start wishing you were indoors. If the air gets just too cold, however, or an icy wind is blowing, the flow of blood to the frostbitten tissue stops altogether, and the tissue begins to die. This is a desperate measure for your body–your blood stays inward to keep your vital organs as warm as possible, sacrificing the extremities. The most severe cases of frostbite can lead to gangrene and amputation. In any case, you should seek medical attention. You should never follow the folk remedy of rubbing frostbitten skin; that will only cause further damage. Nor should you rub snow on it; that, too, will make it worse.