Raynaud’s Phenomenon is a condition that can sometimes be diagnosed by cold fingers. Fingers go white and cold because the small blood vessels in the fingers become narrow. Often the condition will lead to severe colour changes in the finger but not all cases do. When the fingers do change colour they will first have a bluish tint and then go bright red. This is because the narrowed blood vessels use up all of the oxygen to the fingers and when the blood vessels open up again, the blood flows back through. It is something that is typically mild and occurs in infrequent and brief bouts lasting only a few minutes. Usually only the fingers are affected but in some cases the toes and other extremities may be too.
If you have noticed any change in colour to the finger that feels cold, you should speak to a doctor. This can be a sign of something more serious like a blood clot. Tell your doctor exactly which finger it is, if there’s any particular time and situation that you feel this temperature change and if you have any other symptoms.