Table 3.

Body composition and dietary intake of study participants at 4 weeks and 12 weeks after RYGB or VLCD.

Variables	RYGB (n = 16)	VLCD (n = 15)	Mean Difference (95% CI)	p-Value
Weight, kg
4 weeks	100.8 ± 0.8	105.5 ± 0.8	−4.7 (−6.8, −2.7)	<0.001
12 weeks	91.4 ± 0.8	96.1 ± 0.8	−4.7 (−6.8, −2.7)	<0.001
Body mass index, kg/m2
4 weeks	38.0 ± 0.3	37.6 ± 0.3	0.4 (−0.4, 1.1)	0.345
12 weeks	34.6 ± 0.3	34.2 ± 0.3	0.4 (−0.4, 1.1)	0.345
Body fat mass, kg
4 weeks	49.8 ± 0.9	49.2 ± 1	0.6 (−1.8, 3)	0.619
12 weeks	40.6 ± 0.9	40.0 ± 1	0.6 (−1.8, 3)	0.619
% Body fat
4 weeks	48.8 ± 0.8	46.3 ± 0.8	2.5 (0.5, 4.5)	0.014
12 weeks	43.6 ± 0.8	41.1 ± 0.8	2.5 (0.5, 4.5)	0.014
Skeletal muscle mass, kg
4 weeks	28.1 ± 0.3	31.3 ± 0.3	−3.3 (−4.1, −2.4)	<0.001
12 weeks	27.5 ± 0.3	30.8 ± 0.3	−3.3 (−4.1, −2.4)	<0.001
% Skeletal muscle mass
4 weeks	28.1 ± 0.4	29.8 ± 0.4	−1.7 (−2.7, −0.8)	<0.001
12 weeks	30.5 ± 0.4	32.2 ± 0.4	−1.7 (−2.7, −0.8)	<0.001
Waist circumference, cm
4 weeks	111.3 ± 1.8	101.1 ± 1.8	10.3 (5.2, 15.3)	<0.001
12 weeks	97.0 ± 1.8	94.7 ± 1.8	2.3 (−2.8, 7.4)	0.369
Dietary intake
Total energy intake, kcal/d
4 weeks	304.7 ± 38.1	824.8 ± 39.4	−520.1 (−627.6, −412.6)	<0.001
12 weeks	679.3 ± 38.1	875 ± 39.4	−195.7 (−303.2, −88.3)	<0.001
Protein intake, g/d
4 weeks	20.6 ± 4.6	96.3 ± 4.7	−75.8 (−86.4, −65.2)	<0.001
12 weeks	43.8 ± 4.6	119.6 ± 4.7	−75.8 (−86.4, −65.2)	<0.001
Fat intake, g/d
4 weeks	14.6 ± 2.7	23.1 ± 2.8	−8.5 (−16.1, −1.0)	0.027
12 weeks	31.7 ± 2.7	28.7 ± 2.8	3.0 (−4.6, 10.6)	0.438
Carbohydrate intake, g/d
4 weeks	23.7 ± 4.7	48.8 ± 4.8	−25.2 (−38.3, −12)	<0.001
12 weeks	44.7 ± 4.7	48.9 ± 4.8	−4.2 (−17.4, 8.9)	0.528

Data are presented as mean ± standard error or mean difference (95% confidence intervals). RYGB, Roux-en-Y gastric bypass; VLCD, very low-calorie diet.