What is the cause of cold extremities?

Cold extremities mean your body wants to protect you from a heart attack

A study from Harvard University confirmed that the cold weather causing narrowing of the blood vessels can play a role in increasing the risk of heart attack, and that the cold extremities that are felt in the winter are a result of your body trying to protect the internal organs, including the heart and lungs.

The blood vessels contract to protect the heart while the body conserves heat by redirecting heat from the fingers and toes inward.