Such doses of thyroid may, of course, have a beneficial action in a limited number of cases of myxedema and cretinism.
If the thyroid gland was at fault we would have either the low mentality commonly spoken of as cretinism, or myxedema.
The sclerotic process in the arteries is due to the lack of thyroid as in cases of myxedema.
myxedema myx·e·de·ma (mĭk'sĭ-dē'mə)
A disease caused by decreased activity of the thyroid gland in adults and characterized by dry skin, swellings around the lips and nose, mental deterioration, and a subnormal basal metabolic rate.