Why would my hands, feet and other areas on my body get cold for no reason?

Stress, Meds,Thyroid. Stress-yep meds-aspecially beta blockers for heart hyperthyroid or medication imbalance.
Could be Raynaud's. Raynaud's phenomenon is a symptom caused by constriction of small blood vessels, usually in the fingers and toes, leading to a lack of nutrients and oxygen going to the fingers and toes. Raynaud's phenomenon can be due to auto-immune disorders, hormonal imbalances, medication effects, etc... A primary care, endocrinology, or rheumatology doctor can look for raynaud's and other possible disorders.