Table 2.
Mean thyroid stimulating hormone and free T4 levels based on subject BMI group
| Underweight | Healthy weight | Overweight | Obese | P | |||
|---|---|---|---|---|---|---|---|
| All ages | All (850) | TSH | 2.89 ± 1.64 | 3.05 ± 1.85 | 3.22 ± 1.77 | 3.53 ± 2.13 | 0.005* |
| FT4 |
1.41 ± 0.24 |
1.43 ± 0.25 |
1.39 ± 0.27 |
1.39 ± 0.26 |
0.221 | ||
| Male (365) | TSH |
2.78 ± 1.55 |
3.16 ± 1.77 |
3.145 ± 1.69 |
3.75 ± 1.94 | 0.002* | |
| FT4 | 1.41 ± 0.23 | 1.41 ± 0.24 | 1.30 ± 0.26 | 1.42 ± 0.23 | 0.040* | ||
| Female (485) | TSH | 3.02 ± 1.75 | 3.00 ± 1.90 | 3.27 ± 1.83 | 3.31 ± 2.28 | 0.457 | |
| FT4 | 1.40 ± 0.25 | 1.44 ± 0.26 | 1.44 ± 0.26 | 1.36 ± 0.28 | 0.045* | ||
| 2–9 year olds | All (429) | TSH | 2.79 ± 1.58 |
2.98 ± 1.62 |
3.24 ± 1.83 |
3.64 ± 2.18 |
0.005* |
| FT4 | 1.44 ± 0.25 | 1.45 ± 0.24 | 1.44 ± 0.25 | 1.40 ± 0.27 | 0.450 | ||
| Male (155) | TSH | 2.71 ± 1.66 | 3.34 ± 1.84 | 2.23 ± 1.37 | 4.05 ± 1.82 | 0.003* | |
| FT4 | 1.45 ± 0.24 | 1.47 ± 0.21 | 1.44 ± 0.19 | 1.43 ± 0.23 | 0.872 | ||
| Female (274) | TSH | 2.88 ± 1.50 | 2.81 ± 1.48 | 3.43 ± 1.86 | 3.37 ± 2.36 | 0.084 | |
| FT4 | 1.42 ± 0.25 | 1.44 ± 0.25 | 1.44 ± 0.26 | 1.38 ± 0.29 | 0.504 | ||
| 10-18 year olds | All (421) | TSH | 3.03 ± 1.72 | 3.15 ± 2.10 | 3.21 ± 1.74 | 3.44 ± 2.09 | 0.521 |
| FT4 | 1.36 ± 0.23 | 1.41 ± 0.27 | 1.36 ± 0.27 | 1.38 ± 0.25 | 0.463 | ||
| Male (210) | TSH | 2.88 ± 1.41 | 2.99 ± 1.70 | 3.33 ± 1.70 | 3.58 ± 2.00 | 0.138 | |
| FT4 | 1.36 ± 0.21 | 1.36 ± 0.26 | 1.27 ± 0.26 | 1.41 ± 0.23 | 0.057 | ||
| Female (211) | TSH | 3.24 ± 2.11 | 3.26 ± 2.34 | 3.09 ± 1.80 | 3.24 ± 2.20 | 0.984 | |
| FT4 | 1.36 ± 0.25 | 1.44 ± 0.27 | 1.44 ± 0.26 | 1.34 ± 0.27 | 0.087 |
Abbreviations: BMI, body mass index; TSH, thyroid stimulating hormone; FT4, free T4