How Hypothyroidism Causes Weight Gain? When someone has difficulty losing weight in spite of eating healthy and exercising, a doctor would most certainly suggest getting a thyroid panel done, which comprises of TSH (thyroid stimulating hormone), total T4, free T4, T3, free T3, Tg, among other battery of tests to ascertain underlying factors and to treat the problem accordingly. If your thyroid tests return with TSH reading going above 4.0/mU/L with a low T4 level, it indicates a disease called…