Table 4.
Cross-sectional comparison of iodine intake and selected blood markers between omnivore, vegetarian and vegan children aged 6–18 years.
| Parameter | Control OM (n) | Min | Max | Mean (±SD) | Median | IQR | Diet (n) | Min | Max | Mean (±SD) | Median | IQR | p* | Adj. p** | Effect size CI 95% |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Iodine intake | |||||||||||||||
| MDI (µg/day) | 19 | 2.00 | 202.10 | 62.70 ± 46.32 | 45.90 | 32.70–79.05 | VG (37) | 3.00 | 348.30 | 47.02 ± 57.60 | 32.00 | 19.70–58.10 | 0.06 | 0.06 | 0.25 (0.02–0.51) |
| VN (16) | 0.00 | 69.60 | 7.84 ± 17.31 | 0.75 | 0.50–7.80 | 0.00 | 0.00 | 0.76 (0.59–0.85) | |||||||
| Dose of supplement (µg/day) | 24 | 0.00 | 0.00 | 0.00 ± 0.00 | 0.00 | 0.00–0.00 | VG (38) | 0.00 | 150.00 | 17.97 ± 40.41 | 0.00 | 0.00–0.00 | 0.03 | 0.03 | 0.28 (0.17–0.39) |
| VN (18) | 0.00 | 200.00 | 63.89 ± 81.45 | 0.00 | 0.00–137.5 | 0.00 | 0.00 | 0.55 (0.37–0.74) | |||||||
| Markers of iodine status | |||||||||||||||
| TSH [mUI/l] | 23 | 0.86 | 4.35 | 2.26 ± 0.86 | 2.08 | 1.69–2.71 | VG (36) | 0.84 | 4.53 | 2.24 ± 0.88 | 2.08 | 1.72–2.52 | 0.94 | 1.00 | 0.01 (0.00–0.29) |
| VN (17) | 0.91 | 6.40 | 2.53 ± 1.61 | 1.90 | 1.58–2.48 | 0.81 | 1.00 | 0.04 (0.00–0.36) | |||||||
| fT4 [pmol/l] | 23 | 11.21 | 16.97 | 14.25 ± 1.62 | 14.21 | 13.17–15.54 | VG (36) | 11.60 | 20.01 | 14.81 ± 1.76 | 14.74 | 13.63–15.96 | 0.31 | 0.31 | 0.13 (0.00–0.38) |
| VN (17) | 11.69 | 19.42 | 15.26 ± 1.76 | 15.28 | 14.26–16.22 | 0.08 | 0.15 | 0.28 (0.03–0.53) | |||||||
| fT3 [pmol/l] | 23 | 4.92 | 7.75 | 6.56 ± 0.69 | 6.77 | 6.14–7.00 | VG (36) | 4.09 | 8.12 | 6.66 ± 0.89 | 6.81 | 6.11–7.25 | 0.51 | 0.51 | 0.09 (0.01–0.33) |
| VN (17) | 3.42 | 8.60 | 6.18 ± 1.22 | 6.25 | 5.29–6.87 | 0.20 | 0.41 | 0.20 (0.01–0.50) | |||||||
| TG [µg/l] | 23 | 5.64 | 44.95 | 17.72 ± 9.91 | 15.65 | 10.62–23.00 | VG (35) | 0.39 | 54.30 | 17.79 ± 12.19 | 14.79 | 10.49–19.43 | 0.78 | 1.00 | 0.04 (0.00–0.30) |
| VN (14) | 4.98 | 37.15 | 18.13 ± 9.62 | 18.93 | 9.32–21.86 | 0.83 | 1.00 | 0.04 (0.01–0.39) | |||||||
| UIC [µg/l] | 23 | 84.90 | 408.00 | 205.12 ± 93.81 | 177.00 | 156.5–238.50 | VG (36) | 40.10 | 700.00 | 179.37 ± 125.34 | 147.50 | 110.25–210.25 | 0.13 | 0.17 | 0.20 (0.01–0.44) |
| VN (17) | 50.80 | 316.30 | 154.72 ± 66.98 | 157.00 | 114.00–178.00 | 0.08 | 0.17 | 0.28 (0.03–0.55) | |||||||
Values of blood markers were log transformed and adjustment was made for sex and age.
MDI mean daily intake, TSH thyroid-stimulating hormone, fT4 free thyroxine, fT3 free triiodothyronine, TG thyroglobulin, UIC spot urine iodine, OM omnivore, VG vegetarian, VN vegan, n number of subjects, IQR interquartile range, SD standard deviation, CI confidential interval.
*p value calculated using Wilcoxon signed-rank tests; ** adjusted p value calculated using linear regression.