Suffering from cold fingers or toes? There is a medical explanation called Raynaud's phenomenon, a condition in which blood flow to the fingers and toes slows down. It is caused by cold weather or a sudden drop in temperature, resulting in a whiteness and numbness of the fingers and toes.
When the body gets cold and the core body temperature drops, the sympathetic nerve sends a signal to constrict the smaller vessels in the fingers and toes, restricting blood to the arms and legs and in turn increasing it to the internal organs to protect them from cold. In severe cases, there may be a break-down in the tissue in the ends of the fingers and toes resulting in sores which may even lead to ulcerations.