Thyroid hormones in non-insulin-dependent diabetes before and after dietary treatment.

In a group of 8 moderately obese non-insulin-dependent diabetics, both serum total T3 and T4 concentrations and serum free T3 and T4 concentrations were significantly lower than control values. Serum TBG levels did not differ. Five patients demonstrated an apparently successful response to dietary treatment with loss of symptoms and glycosuria and fall in post-prandial blood glucose and HbA1. Serum concentrations of thyroid hormones and TBG, however, were not significantly altered. These abnormalities may be unrelated to hyperglycaemia and may reflect the nutritional status of the patients.