Why do I have cold hands? Even when it is not cold inside or out?

Cold hands. Do they turn red, white, & blue? Do you smoke? You may have either raunaud's disease (vascular spasm) [http://www.Mayoclinic.Com/health/raynauds-disease/ds00433/dsection=symptoms or buerger's disease (inflamed, swollen, clotted blood vessels—associated with smoking) [http://www.Mayoclinic.Com/health/buergers-disease/ds00807] see doc for eval & treatment. Stop smoking!
Could be nothing. Cold hands can simply be cold hands.. Concerning symptoms would be color changes such as white to blue to red and sores on the fingers that do not heal. Low thyroid function sometimes can cause these types of symptoms. Sometimes hormonal changes can cause it. Poor circulation would be a source and smoking are causes. If symptoms are new, probably worth seeing your doctor.