Desiccated thyroid in a nutritional supplement

Abstract

Nutritional or vitamin supplements, which are largely unregulated by the Food and Drug Administration (FDA) and are sold in health food stores and through mail-order catalogs, may contain various combinations and doses of vitamins, minerals, herbs, chemicals, and animal tissues. Some of the products marketed as nutritional supplements contain desiccated porcine or bovine thyroid. A patient came to our family practice center with resting tachycardia, amenorrhea, and weight loss. She had been taking a nutritional supplement containing desiccated thyroid for 3 months. Laboratory studies confirmed the presence of hyperthyroidism. The daily recommended and consumed dose of the product she had been taking exceeded the normal replacement dose by two to three times. There is potential for harm in the unregulated availability and distribution of desiccated thyroid to the public.