Table 3.
Measures of Biological Safety Biomarkers (Mean and Standard Error) by Daily D Dose Group During 6 Months’ Supplementation With 600, 1000, or 2000 IU/d of Vitamin D3a
| Baseline |
3 Months |
6 Months |
|
|---|---|---|---|
| Alkaline phosphatase, μg/L | |||
| 600 IUb | 228.2 (5.9) | — | 237.7 (7.9) |
| 1000 IUc | 234.9 (6.2) | — | 249.5 (8.3) |
| 2000 IUd | 245.9 (5.9) | — | 239.9 (7.9) |
| P value among dose groups | 0.10 | — | 0.55 |
| Calcium, mg/dL | |||
| 600 IUb | 9.6 (0.03) | 9.7 (0.02) | 9.7 (0.03) |
| 1000 IUc | 9.6 (0.03) | 9.7 (0.02) | 9.6 (0.03) |
| 2000 IUd | 9.6 (0.03) | 9.7 (0.02) | 9.6 (0.03) |
| P value among dose groups | 0.55 | 0.86 | 0.22 |
| Phosphorus, mg/dL | |||
| 600 IUb | 4.8 (0.04) | 4.9 (0.03) | 4.9 (0.04) |
| 1000 IUc | 4.8 (0.04) | 4.9 (0.03) | 4.9 (0.04) |
| 2000 IUd | 4.8 (0.04) | 4.8 (0.03) | 4.9 (0.04) |
| P value among dose groups | 0.69 | 0.31 | 0.79 |
| PTH, pg/mL | |||
| 600 IUb | 35.2 (1.1) | — | 36.7 (1.3) |
| 1000 IUc | 35.0 (1.2) | — | 34.7 (1.3) |
| 2000 IUd | 33.9 (1.1) | — | 32.6 (1.3) |
| P value among dose groups | 0.71 | — | 0.08 |
a
Estimates are from linear mixed models with repeated measurements at two time points (3 and 6 months), three dose groups (600, 1000, and 2000 IU), and unstructured covariance structure.
b
n = 207, 199, and 188 at baseline, 3 and 6 months, respectively.
c
n = 190, 189, and 173 at baseline, 3 and 6 months, respectively.
d
n = 207, 202, and 190 at baseline, 3 and 6 months, respectively.