Low metabolic rates are found in conditions in which the thyroid gland does not appear to be involved. It was shown in preceding papers1that hypercholesteremia was characteristic of thyroid deficiency regardless of observed metabolic rates. This report therefore deals with observations on the blood cholesterol in other conditions in which hypometabolism was encountered. In evaluating the basal metabolism test, it is important to remember two things: (1) that it is probably impossible to obtain true basal metabolic rates in some persons because of nervousness or lack of cooperation, and (2) that repetition of the basal metabolism test and keeping the subject in the hospital overnight will tend to give lower readings than are obtained when these procedures are not carried out. In other words, the metabolism is subject to influences which are often beyond the examiner's control. Thus, while groups may show various trends, individual cases may occasionally