Conditions that may cause variations in body temperature 1. HYPOTHYROIDISM 2. ADRENAL FATIGUE 3. ALTERED INSULIN SENSITIVITY 4. SEPTICEMIA 1. HYPOTHYROIDISM If you feel cold, then suddenly you’re hot without adjusting the room temperature, it may be due to a thyroid problem. Thyroid, an endocrine gland located above the collarbone, is responsible for regulating the metabolism, heart rate and body temperature. When this gland produces too much thyroid hormone, your temperature increases; on the other hand, when the production of T3 and T4 decreases, your body temperature drops as well. These two hormones control the way your body uses its energy, and low levels of thyroid hormones lead to a slow metabolism and to symptoms like fatigue and weakness, depression, constipation, increased sensitivity to cold, brittle nails and hair and heavier menstrual flow in women. I hope you happy with information kindly rate it. thank you.