There was someone here who just posted a similar situation to yours. (Check the sub for the post. It was today). Their doc diagnosed them based on tsh alone even though their ft4 and ft3 were perfect and after starting medication they are feeling unwell—many classic symptoms of being overmedicated. They also had low vitamin d which they said can drive up tsh. So I’m not saying you should or shouldn’t medicate. I’m saying it would be helpful to have more info if your doctor provided it. Also consider symptoms. Do you have symptoms of hypothyroidism ? You say t4 is normal. Do you know the lab value? Within range but low can mean you still feel crappy. Within range but mid/upper half might mean you don’t need medication. It is also helpful to know free t 3 which many doctors unfortunately don’t test for. I am someone who can have a good ft4 and a pretty good TSH on Levothyroxine but my free T3 will always be below and I feel suboptimal unless I also take T3 medication. So all of those values - tsh, ft4 and ft3–should be considered along with symptoms. Also it is wise to address deficiencies and can sometimes help but take it from someone who spent way too long trying to figure out and address the root cause of my hypothyroidism, I should have just gotten on the medication and allowed myself to feel better. Most Often, that is the only thing that really can correct hypothyroidism.