Table 2.
Frequency of suboptimal levels of vitamin D (s-25(OH)D <50 nmol/l) and vitamin D deficiency (s-25(OH)D <25 nmol/l) for the children in total (all blood values, n 158), and for the groups taking and not taking fish-liver oil or other vitamin D supplements (data presented are for the children who returned valid 3 d food records and had blood sampled, n 120); 7-year-old Icelandic girls and boys, Reykjavík, 2006
| Food records (n 120)† | ||||||
|---|---|---|---|---|---|---|
| All blood samples (n 158) | Take fish-liver oil or other vitamin D supplement (n 51) | Do not take fish-liver oil or other vitamin D supplement (n 69) | ||||
| n | % | n | % | n | % | |
| Suboptimal levels of vitamin D (<50 nmol/l) | 103 | 65 | 25 | 49 | 49 | 71 |
| Girls | 58 | 68 | 12 | 55 | 30 | 73 |
| Boys | 45 | 62 | 13 | 45 | 19 | 68 |
| Thereof, vitamin D deficiency (<25 nmol/l) | 5 | 3 | 1 | 2 | 3 | 4 |
| Girls | 3 | 3 | 0 | 2 | 5 | |
| Boys | 2 | 3 | 1 | 3 | 1 | 4 |
s-25(OH)D, serum 25-hydroxyvitamin D.
Significance values were computed with χ 2 tests. There was no gender difference in suboptimal levels or vitamin D deficiency for all samples (P = 0·68). There was a significant difference in suboptimal levels and vitamin D deficiency between those taking and not taking fish-liver oil or other vitamin D supplements (P = 0·02), irrespective of gender.
†A total of sixty-three girls and fifty-seven boys both returned 3 d food records and had blood tested (n 120).