FIGURE 4.

Mean ± SEM serum 25-hydroxyvitamin D₃ concentration versus time curve after a single dose of oral 900 µg vitamin D₃ or 25-hydroxyvitamin D₃ in healthy participants (n = 10) and patients with intestinal malabsorption of vitamin D (n = 6). Using the Wilcoxon signed-rank test, the AUC of 25(OH)D₃ for the 25(OH)D₃ arm was statistically significantly higher than the AUC of 25(OH)D₃ for the vitamin D₃ arm in both healthy participants (mean ± SEM: 3128 ± 545 vs. 1463 ± 331 ng · h/mL; P < 0.001) and malabsorptive patients (mean ± SEM: 2667 ± 735 vs. 1491 ± 473 ng · h/mL; P < 0.001). 25(OH)D₃, 25-hydroxyvitamin D₃. Reproduced with permission; copyright Holick, 2021.