4. Overactive thyroid
The thyroid gland plays a part in several bodily functions, metabolism being one of them. When the thyroid produces too much hormone, your calorie burn skyrockets and unintended weight loss is the result. You may find the pounds falling away, even if you eat a lot.
If you have hyperthyroidism, you may also experience a fast and irregular heart rate, trouble sleeping, hand tremors, anxiety, or heat intolerance. There are several potential causes of hyperthyroidism, so treatment may involve attention to the underlying condition.
Common approaches to treatment include thyroid medications, beta-blockers, radioactive iodine, or even surgery.