title: A longitudinal study of the relationship between vitamin A supplementation and plasma retinol, retinyl esters, and liver enzyme activities in a healthy elderly population.
abstract: This study examined the association between dietary supplementation with vitamin A and biochemical symptoms of toxicity in 116 healthy elderly volunteers (47 male, 69 female), aged 64-88 y. Plasma retinol and retinyl ester concentrations, seven liver-function tests, and dietary and supplemental vitamin A intakes were measured annually for 5 y. Supplemental intake range was 0-47,000 IU/d; dietary intake range was 2528-23,032 IU/d. Fasting retinol and retinyl ester concentrations were determined by HPLC and dietary intake was assessed by a 3-d food record. Supplemental vitamin A intake was highly correlated with retinyl ester concentrations (r = 0.74, P = 0.0001). Retinyl esters ranges from 3.4% to 10.2% of retinol concentrations. Retinyl ester concentrations did not increase over time, regardless of supplement amount. The association of retinyl esters and liver-function tests was significant only for aspartate aminotransferase activity in females (r = 0.47, P = 0.0001). The supplementation amount in this study was not associated with vitamin A toxicity.
authors.affiliation: Department of Pathology, University of New Mexico School of Medicine, Albuquerque 87131-5666.
authors.forename: P M
authors.initials: PM
authors.lastname: Stauber
authors.forename: B
authors.initials: B
authors.lastname: Sherry
authors.forename: D J
authors.initials: DJ
authors.lastname: VanderJagt
authors.forename: H N
authors.initials: HN
authors.lastname: Bhagavan
authors.forename: P J
authors.initials: PJ
authors.lastname: Garry
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism* / Q000502:physiology; D015930:Diet Records; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008099:Liver / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology; D008111:Liver Function Tests; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D012016:Reference Values; D014801:Vitamin A / Q000097:blood* / Q000494:pharmacology*
chemical_list: D014801:Vitamin A