All these evaluated index measure central resistance (pituitary gland) inhibition by FT4 levels (10); the proposal of the concept of acquired resistance to TH in the general population also provides some plausible biological mechanisms for the relationship between thyroid function and many other metabolic syndromes, including hyperuricemia, obesity, and cardiovascular disease, beyond NAFLD. Here, TH is linked to obesity due to melanocortin 4 receptor deficiency.