Fortification of orange juice with vitamin D2 or vitamin D3 is as effective as an oral supplement in maintaining vitamin D status in adults1234

Background: Vitamin D has been added to calcium-fortified orange juice. It is unknown whether vitamin D is as bioavailable from orange juice as it is from supplements. Objectives: The objective was to compare the bioavailability of vitamin D 2 and vitamin D 3 from orange juice with that from vitamin D 2 and vitamin D 3 supplements. A secondary aim was to determine which form of vitamin D is more bioavailable in orange juice. Design: A randomized, placebo-controlled, double-blind study was conducted in healthy adults aged 18–84 y (15–20/group) who received 1000 IU vitamin D 3 , 1000 IU vitamin D 2 , or placebo in orange juice or capsule for 11 wk at the end of winter. Results: A total of 64% of subjects began the study deficient in vitamin D (ie, 25-hydroxyvitamin D [25(OH)D]) concentrations 0.1). Similarly, no significant difference in serum 25(OH)D 2 was observed between subjects who consumed vitamin D 2 –fortified orange juice and vitamin D 2 capsules ( P > 0.1). No significant overall difference in parathyroid hormone concentrations was observed between the groups ( P = 0.82). Conclusion: Vitamin D 2 and vitamin D 3 are equally bioavailable in orange juice and capsules.