Table 1.

Characteristics of MZ cotwins discordant and concordant for obesity

	Discordant Pairs		Concordant Pairs
	Heavier	Leaner	Heavier	Leaner
No. of subjects	14	14	10	10
Age, yr	25.7±1.5	25.6±1.5	25.6±1.2	25.7±1.2
Birth weight, g	2588±481	2464±526	2537±702	2581±595
Height, cm	171±9	171±9	173±8	173±7
Body weight, kg	89.8±9.4	74.5±8.8‡	81.5±22.1	78.9±20.7*
BMI, kg/m2	30.6±2.0	25.4±1.8‡	27.3±7.4	26.3±7.2†
%Body fat	38.3±6.5	29.5±8.5‡	27.0±11.7	24.8±11.8*
Fat mass, kg	34.0±5.1	21.4±5.7‡	21.0±10.6	18.9±10.3*
LBM, kg	52.8±9.8	50.4±10.2*	53.6±10.9	53.8±10.3
M value/LBM, mg·kg LBM–1·min–1	6.1±2.1	9.1±2.9†	7.5±3.2	7.4±2.8
Blood hemoglobin, g/l	144±11	140±11	144±12	145±10

Data shown as mean ± SD. MZ, monozygotic; LBM, lean body mass.

^*P < 0.05,

^†P < 0.01,

^‡P < 0.001 (Student's paired t-test).