Effects of Cholesterol and Cholic Acid Supplements on Rats Fed Low Iodine Diets

The addition of cholesterol and cholic acid to a purified diet low in iodine fed to young female rats was found to increase the degree of thyroid enlargement caused by the iodine deficiency. The supplement accentuated the loss of stainable colloid and the degree of hyperplasia. The I131 uptake at 24 hours did not appear to be affected by the cholesterol-cholic acid supplementation, but the loss of I131 from the thyroid in the subsequent 5 days was increased. From data obtained with diets containing small amounts of additional iodate it appears that the iodine requirement was increased by the cholesterol-cholic acid supplements.