Vitamin D-Fortified Bread Is as Effective as Supplement in Improving Vitamin D Status: A Randomized Clinical Trial.

Abstract

Bread can potentially be a suitable vehicle for fortification with vitamin D. This study was undertaken to evaluate the following: 1) the bioavailability of vitamin D from the fortified Iranian bread and 2) the possible effects of daily consumption of the fortified bread on certain health aspects. This was a randomized, double-blind, placebo-controlled trial conducted over 8 weeks in 90 healthy subjects aged 20-60 years. Subjects were randomly allocated to one of three groups: 1) fortified bread (FP; 50 g bread fortified with 25 μg vitamin D3 plus placebo daily; n = 30); 2) supplement (SP; 50 g plain bread plus 25 μg vitamin D supplement daily; n = 30); and 3) control (CP; 50 g plain bread plus placebo daily; n = 30). Initial and final anthropometric and biochemical assessments were performed. The within-group changes of serum 25-hydroxyvitamin D concentrations were 39.0 ± 22.6 (P < .001), 28.9 ± 31.2 (P < .001), and -9.2 ± 12.3 nmol/L in the FP, SP, and CP groups, respectively. Only in FP and SP groups, serum intact PTH concentrations decreased approximately 13.5% and 14.5%, respectively. Visceral fat also showed a significant decrement in FP (-1.05% ± 1.4%; P ≤ .001) and SP (-0.96% ± 1.7%; P = .006). Serum low-density lipoprotein cholesterol concentration showed a within-group reduction in FP (-10.4 ± 11.2 mg/dL; P < .001) and an insignificant decrement in SP (-6.6 ± 20.2 mg/dL; P = .083). Serum high-density lipoprotein increased in both vitamin D-supplemented groups (FP: 9.7 ± 7.6 vs SP: 5.7 ± 6.7 mg/dL; P < .001). Vitamin D-fortified bread could be potentially effective in raising circulating 25-hydroxyvitamin D levels of the population to nearly adequate levels.