Radioactive Fat Absorption Patterns

ATHEROSCLEROSIS and its accompany18x ing vascular lipoidosis has been linked to an inborn error in fat metabolism. The observations that atheroselerosis and hypercholesterolemia frequently coexist,l 2 that both can be produced in animals following cholesterol feedings,3 and that atherosclerosis is unusual when people eat little animal fat, favor this concept.4-5 The unusual physical state and the abnormal ratio of certain circulating lipids that have been noted in patients with atherosclerosis,9-12 as well as the increased cholesterol content of the actual vascular lesions13-15 also support this view. However, in spite of these and other subtle correlations, an unequivocal relation has not been established between atherosclerosis in man and a disturbance in lipid metabolism. In 1949 Thannhauser and Stanley reported a method for the study of the metabolism of neutral fat in human subjects utilizing 1131labeled olive oil.l6 It had several distinct advantages: (1) the required amount of labeled fat was small and well tolerated, (2) the radioactive iodine was easily measured in the serum, (3) the proportion of the radioactive iodine that split off the fatty acid molecule could be determined and information