The causes of cold hands and feet in newborns are as follows: 1, insufficient blood supply to the peripheral circulation: mostly caused by infectious fever, if the newborn fever cold extremities, more pathological infection, if the extremities are warm, more muffled fever; 2, hypothyroidism: low basal metabolism and performance of cold hands and feet, and even a reduction in the number of stools easy to constipation, at this time need to check the five thyroid to confirm the diagnosis; 3, malnutrition: the amount of calories or protein intake is insufficient, the lack of mineral circulation leads to metabolic disorders.