Table 1 Basic characteristics of the study population (n = 762)
Fortification group | Control group | p value | |
|---|---|---|---|
Participants (n) | 377 | 385 | – |
Female/male (n) | 191/186 | 199/186 | 0.7771 |
Age (n) | 0.5430 | ||
4–10 years | 94 | 91 | 0.5893 |
11–17 years | 75 | 88 | 0.7064 |
18–40 years | 111 | 87 | 0.4928 |
41–60 years | 97 | 119 | 0.4802 |
BMI (kg/m2) | 21.7 (21.17–22.3) | 21.9 (21.3–22.4) | 0.5515 |
25(OH)D (nmol/L) | |||
Baseline | 72.7 (70.8–74.7) | 71.1 (68.9–73.3) | 0.4688 |
End | 67.1 (65.2–69.0) | 41.5 (39.6–43.5) | <0.0001 |
PTH (ng/L) | |||
Baseline | 35.3 (34.1–36.5) | 34.5 (33.3–35.7) | 0.2473 |
End | 36.8 (35.5–38.1) | 40.1 (38.7–41.6) | 0.0199 |
Total calcium (mmol/L) | |||
Baseline | 2.44 (2.43–2.45) | 2.45 (2.44–2.46) | 0.0438 |
End | 2.43 (2.42–2.44) | 2.43 (2.42–2.44) | 0.8165 |
Total vitamin D intake (μg/day) | |||
Baseline | 2.9 (2.8–3.1) | 2.7 (2.5–2.9) | 0.4972 |
End | 11.7 (11.0–12.4) | 4.1 (3.8–4.5) | <0.0001 |
Supplement users (n) | |||
Baseline | 127 | 127 | 0.7163 |
End | 230 | 242 | 0.5991 |
Ski and sun vacation during the study (n) | 135 | 100 | 0.0006 |
Solarium users during the study (n) | 0 | 8 | 0.0059 |
Sunscreen use (n) | |||
Always/most times/sometimes/seldom | 82/108/144/36 | 105/114/132/32 | 0.3361 |