What are normal tsh levels?

It's controversial: There is broad consensus that a TSH between 0.3-2.5 is normal (assuming no pituitary problem exists), and broad consensus that TSH levels above 10 are abnormal and should be treated. A middle-of-the-road approach might be to say that levels between 5-10 are abnormal, and treatment is likely to be beneficial, and that values between 2.5-5 may be abnormal, and that treatment may be beneficial.

Normal TSH Levels: Run between 0.5-5 mIU/L. Remember that TSH is opposite what you would normally think. Low TSH levels mean that you are HYPERthyroid. High TSH levels mean that you are HYPOthyroid. Hope this helps!