It is concluded that the higher circulating levels of insulin cause increased thyroid proliferation. The clinical manifestations are the larger thyroid volume and the formation of nodules. Thus, the thyroid gland appears to be another victim of the insulin resistance syndrome.

We conclude that such a high prevalence of IR would be an important risk factor for developing DTC, as it is well known with some other nonthyroid carcinomas.

We conclude that M produced a significant decrease in the nodular size in patients with IR and small thyroid nodules, whereas the combination of M with L-T₄ was the best treatment in these women.

IR is associated with SCTox of either endogenous or exogenous origin. However, based on our findings of lower IS compared with the rest of the SCTox groups, the endogenous subclinical form might have an even larger metabolic impact.