The median TSH for our age and gender is about 2-2.2 (table in below link). I'm a 69 yo woman that has had hypothyroidism for ~25 years. I do best with a TSH of about 1, and certainly less than 2. A TSH of 3 gives me constipation, fatigue, and have to starve myself to keep my weight under control. TSH is a hormone from the pituitary glad that helps regulate thyroid hormone levels; normal range is about 0.4 to 5.5. My T3 and T4 levels (thyroid hormones) are within normal range even with TSH levels of 0.15 to 3 (0.15 approaches hyperthyroid). My doctor doesn't believe me when I tell her I have hypothyroid symptoms with a TSH of 3 because my free T3 and T4 thyroid hormone levels were normal range. She finally increased my Synthroid and I'm back to my normal (no constipation, being able to eat normally, biking/hiking). I collect autoimmune diseases (celiac, collagenous colitis, Reiters...) but am able to control them with diet (food logs are handy to see if you have any food intolerances), exercise, enough sleep, and managing stress. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5794073/