Taking US RDA of magnesium in a well absorbed form such as citrate or glycinate? Also Epsom Salt is Mg sulfate. Some like the effect of a foot bath.
Getting enough fluids, electrolytes?
Ever get a thyroid blood test that included Free T3? Ever try some selenium supplementation, maybe 100-200mcg in the selenomethionine or Se yeast forms? The body needs Se to make T3 hormone.