title: Bioavailability of beta-carotene in humans.
abstract: Normal healthy volunteers were studied after they ingested various beta-carotene doses. Daily administration of 15 or 45 mg beta-carotene resulted in significant increase in plasma beta-carotene levels. The extent of increase and the pattern of plasma beta-carotene levels showed substantial interindividual variation. Absorption of beta-carotene was affected by dietary fat concentration. Individuals placed on a high-fat diet showed significant increases in plasma beta-carotene as compared with those placed on a low-fat diet. Pharmacological doses of beta-carotene (45 and 90 mg) were used in intermittent schedules (5-6 d intervals) without altering the steady state of beta-carotene plasma levels. Yellowing of the skin occasionally occurred during daily dosing with 45 mg beta-carotene without evidence of toxicity. The observed individual variation in bioavailability of beta-carotene raises questions regarding clinical use of this micronutrient. It appears that determination of target plasma beta-carotene concentrations is essential for effective use of this compound in prevention or treatment.
authors.affiliation: Department of Medicine, Michigan State University, East Lansing.
authors.forename: N V
authors.initials: NV
authors.lastname: Dimitrov
authors.forename: C
authors.initials: C
authors.lastname: Meyer
authors.forename: D E
authors.initials: DE
authors.lastname: Ullrey
authors.forename: W
authors.initials: W
authors.lastname: Chenoweth
authors.forename: A
authors.initials: A
authors.lastname: Michelakis
authors.forename: W
authors.initials: W
authors.lastname: Malone
authors.forename: C
authors.initials: C
authors.lastname: Boone
authors.forename: G
authors.initials: G
authors.lastname: Fink
mesh_terms: D000328:Adult; D001682:Biological Availability; D002338:Carotenoids / Q000378:metabolism*; D004041:Dietary Fats / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008297:Male; D014801:Vitamin A / Q000097:blood; D019207:beta Carotene
chemical_list: D004041:Dietary Fats; D019207:beta Carotene; D014801:Vitamin A; D002338:Carotenoids