Table 4. Result of subgroup analysis of included studies in meta-analysis.

Sub-grouped by			No. of trials	Effect size*	95% CI, p value	I2 (%)	p for heterogeneity	p for between subgroup heterogeneity
Leptin			9	−0.80	(−1.70, 0.08), 0.076	94.6	< 0.001
	Duration (wk)							0.199
		< 8	1	0.05	(−0.75, 0.85), 0.903	-	-
		≥ 8	8	−0.92	(−1.90, 0.07), 0.068	95.2	< 0.001
	Dose (g/d)							< 0.001
		≤ 10	4	−0.19	(−0.45, 0.08), 0.162	0.0	0.803
		> 10	3	−2.28	(−5.86, 1.29), 0.211	98.4	< 0.001
	Sex							0.302
		Female	2	−0.20	(−0.73, 0.34), 0.470	0.0	0.937
		Both	7	−0.99	(−2.10, 0.12), 0.081	95.9	< 0.001
	Baseline BMI (kg/m2)							< 0.001
		< 30	7	−0.22	(−0.43, −0.01), 0.048	0.0	0.975
		≥ 30	2	−3.17	(−9.49, 3.15), 0.326	99.0	< 0.001
	Study population							< 0.001
		Overweight–Obese	5	−0.22	(−0.51, 0.07), 0.137	0.0	0.959
		MetS	1	0.02	(−0.70, 0.74), 0.958	-	-
		T2DM	2	−3.21	(−9.44, 3.02), 0.313	99.2	< 0.001
		Healthy	1	−0.31	(−0.71, 0.09), 0.131	-	-
Adiponectin			16	−0.49	(−1.20, 0.21), 0.167	95.4	< 0.001
	Duration (wk)							0.079
		< 8	5	−0.16	(−0.65, 0.33), 0.534	61.3	0.035
		≥ 8	11	−0.83	(−1.82, 0.16), 0.102	96.8	< 0.001
	Dose (g/d)							0.001
		≤ 10	5	−0.38	(−0.87, 0.10), 0.123	69.1	0.012
		> 10	10	−0.94	(−2.10, 0.22), 0.114	97.0	< 0.001
	Sex							0.127
		Male	4	−9.69	(−14.28, −5.11), < 0.001	98.7	< 0.001
		Female	4	0.29	(−0.13, 0.71), 0.183	30.9	0.229
		Both	8	−0.35	(−0.97, 0.26), 0.264	91.9	< 0.001
	Baseline BMI (kg/m2)							< 0.001
		< 30	9	−1.59	(−2.93, −0.25), 0.020	97.0	< 0.001
		≥ 30	7	0.18	(−0.19, 0.55), 0.344	65.4	0.008
	Study population							< 0.001
		Overweight–Obese	10	−1.16	(−2.38, 0.06), 0.062	96.7	< 0.001
		MetS	2	−0.05	(−0.52, 0.42), 0.833	0.0	0.647
		T2DM	2	0.32	(−0.67, 1.32), 0.526	85.8	0.008
		Healthy	2	−0.68	(−1.32, −0.05), 0.034	50.0	0.155

The p value < 0.05 was considered statistically significant.

MetS, metabolic syndrome; T2DM, type 2 diabetes; CI, confidence interval.

^*Calculated by random-effects model.