what is considered normal tsh
Normal TSH levels. Normal TSH levels for the average adult range from 0.4 â 4.0 mIU/L (milli-international units per liter) (3). However, many organisations agree that a reading of 2.5 or less is truly ideal, with anything 2.5 â 4.0 mIU/L considered âat riskâ. For those on thyroxine, goal TSH level is between 0.5 to 2.5 mU/L.