There are numerous reports in the literature regarding the effects of thyroid feeding in animals. There are only a few reports dealing with the effect of large doses of thyroid in man. The following case report is of interest because of the huge doses of thyroid extract consumed over a period of one year, by an individual subsequently proved unstable, for the concealed purpose of self-destruction. CASE REPORT: On December 4, 1941, a white, married, 28 year old woman presented herself for weight reduction. The past history revealed the usual childhood diseases, a tonsillectomy at age 5, but no serious.