Vitamin A concentration in human tissues collected from five areas in the United States

Abstract
1) Carotenoids in human tissues were in low and variable concentrations. Approximately 50% of the total carotenoids was present as carotene. The adrenal was the only tissue that consistently contained appreciable levels of carotenoids. 2) Tissue vitamin A concentration, except for liver, was approximately 1 µg/g wet tissue and was independent of liver vitamin A concentration. 3) Livers from 372 subjects from five geographic locations (Missouri, Iowa, Ohio, California, and Texas) were found to contain an average vitamin A concentration of 146 ± 151 µg/g of wet liver, a median value of 106 µg/g, and a range of 1 to 5,500 µg/g. Forty-seven subjects who died from accidental causes had an average of 107 ± 81 µg/g, median of 96 µg/g, and a range of 1 to 4,400 µg/g. 4) There was a large and significant regional difference in the average concentration of liver vitamin A and in the incidence of low (less than 40 µg/g) concentration levels. The overall incidence was 22%. 5) No correlation was found between the probable cause of death, socioeconomic status, or adipose pesticide concentration, and liver vitamin A stores. Liver samples from subjects who died from accidental causes tended to have less vitamin A than subjects who died from disease-related causes. 6) The liver vitamin A data reported in this study were in general agreement with other recent data from the United States and Canada that showed 20 to 30% of the populations tested were in the poor risk group regarding vitamin A nutriture.