Table 2.

Body Composition and Energy Expenditure in the Low-Normal TSH and High-Normal TSH Groups

Measurea	Low-Normal TSH (n = 88)	High-Normal TSH (n = 52)	P Values for Comparing Groupsb
BMI, kg/m2	27.3 ± 0.6c	27.8 ± 0.9	0.32
Lean body mass, kg	43.8 ± 0.8	45.1 ± 1.3	0.19
Fat mass, kg	28.0 ± 1.1	30.2 ± 1.9	0.81
% Fat mass	37. 0 ± 0.8	37.7 ± 1.1	0.99
Visceral fat, g in abdominal ROI	474 ± 29	511 ± 43	0.44
TEE, kcal/d	2163 ± 60	2273 ± 100	0.23
TEE/LBM, kcal/kg/d	48.1 ± 1.0	48.9 ± 1.4	0.90
REE, kcal/d	1309 ± 21	1348 ± 33	0.76
REE/LBM, kcal/kg/d	28.5 ± 0.3	28.6 ± 0.4	0.12
CHO oxidation, g/d	136 ± 6	140 ± 10	0.92
Fat oxidation, g/d	56.5 ± 2.8	58.6 ± 4.4	0.81
Protein oxidation, g/d	54.4 ± 2.1	58.7 ± 2.5	0.52
TEF,d kcal/d	142 ± 8	141 ± 12	0.67
TEF peak energy, kcal	33.3 ± 0.7	34.9 ± 1.2	0.76
TEF time to peak, h	1.81 ± 0.11	1.62 ± 0.14	0.19

Abbreviations: CHO, carbohydrate; ROI, region of interest; TEF, thermic effect of food, calculated from 6-hour TEF area under the curve multiplied by 3.5 to estimate total daily TEF.

^aBody composition values were available for all subjects except for one low normal subject missing visceral fat value. TEE values were available for 41 low normal and 21 high normal subjects. REE values were available for all subjects. Substrate oxidation values were available for all low normal (except for one CHO value) subjects and all but three CHO, two fat, and three protein high-normal values. TEF values were available for 59 low-normal and 29 high-normal subjects. The following measures were analyzed together to allow for correlations between measures: BMI, LBM, and fat mass; TEE and TEE/LBM; REE and REE/LBM; CHO, fat, and protein oxidation; and TEF peak energy and time to peak.

^bP values were adjusted for age, estrogen status, L-T4 time, L-T4 dose time, and L-T4 dose (μg/kg).

^cValues are means ± SEM.

^dTEF models were also adjusted for LBM, %fat, and meal size.