Why do my fingers turn white in the cold?

The pattern has a name: Raynaud's phenomenon. The NHS describes it as blood stopping flowing properly to your fingers and toes in response to cold, anxiety, or stress - the small arteries in your fingers overreact to temperature and clamp shut. The colour sequence is the signature: fingers turn white as blood leaves, often blue as the trapped oxygen runs out, then red and tingly or painful as flow returns. Add numbness or pins and needles and the picture is complete. The NHS calls it common and says it does not usually cause severe problems - the common form (primary Raynaud's) is an overreaction, not a disease, and warmth is the treatment: gloves before you get cold, not after; warm the whole body (a cold core steals blood from hands); warm water on the hands when an attack starts; and no smoking, since nicotine constricts vessels. The reason to mention it to a GP rather than simply live with it: Raynaud's that starts later in life, is severe or asymmetric, comes with joint pain, rashes, or mouth ulcers, or leaves sores on the fingertips can be the secondary type - MedlinePlus notes it can be linked to other conditions, so the NHS advises getting it checked. If a fingertip ever turns white and stays white, numb, or develops a sore that will not heal, that is a same-week appointment, not a wait-for-spring. Pymander is a free AI doctor, 24/7 by text, that can help you map your pattern.