Impact of Thyroid Hormones on Human Glucose and Energy Metabolism

This study examines how thyroid hormones affect the way the body processes glucose (blood sugar) and manages energy in patients with either Graves' disease (an overactive thyroid) or thyroid cancer. **You may be eligible if...** - You have been newly diagnosed with Graves' disease (an immune condition causing an overactive thyroid), OR - You have been diagnosed with thyroid cancer **You may NOT be eligible if...** - You have diabetes mellitus - Your fasting blood sugar is 200 mg/dL or higher - You currently use insulin that is still active in your body at the time of the test - You have an acute illness that is activating stress hormones - You are in a post-surgical recovery or acute infection state Talk to your doctor to see if this trial is right for you.