Table 3.

Results of dose subgroup.

Factor	Zinc dose	Number of studies	Heterogeneity test			Weighted mean difference
			Q	I 2	P value	WMD	[95% CI]	P value
Serum zinc (ug/dL)	<45 mg	4	2.27	27.52%	0.211	30.792	[23.781, 44.201]	<0.001∗
	45–50 mg	6	121.15	95.90%	<0.001	23.831	[4.824, 42.837]	0.014∗
	>50 mg	3	18.01	88.90%	<0.001	32.692	[20.111, 45.273]	<0.001∗
BMI (kg/m2)	16.5 mg	1	-	-	-	0.530	[−3.769, 2.709]	0.621
	≥90 mg	2	1.16	13.70%	0.282	0.124	[−1.062, 1.309]	0.838
nPNA (g/kg/d)	11 mg	1	-	-	-	0.41	[0.292, 0.528]	<0.001∗
	45 mg	2	1.3	23.00%	0.250	0.019	[−0.130, 0.167]	0.805
Dietary protein intake (g/kg/d)	45 mg	2	0.64	0.00%	0.425	5.605	[−0.527, 11.736]	0.073
	50 mg	2	0.53	0.00%	0.467	5.373	[−1.351, 12.097]	0.117
Albumin (g/dL)	<50 mg	2	6.96	85.60%	0.008	0.37	[−0.225, 0.966]	0.223
	≥50 mg	2	2.35	57.40%	0.125	0.309	[−0.343, 0.962]	0.353
Hemoglobin (g/dL)	<45 mg	2	3.62	71.87%	0.054	1.018	[−0.188, 2.223]	0.098
	≥45 mg	2	0.08	0.00%	0.780	0.385	[−0.307, 1.078]	0.275
HDL (mg/dL)	<50 mg	2	31.35	96.80%	<0.001	4.083	[−14.455, 22.621]	0.666
	≥50 mg	2	10.09	96.80%	<0.001	0.031	[−6.494, 6.556]	0.993
LDL (mg/dL)	<50 mg	2	4.84	79.40%	0.028	6.088	[−25.371, 37.548]	0.704
	≥50 mg	2	0.46	0.00%	0.496	44.792	[34.951, 54.632]	<0.001∗
TC (mg/dL)	≤50 mg	2	0.03	0.00%	0.857	37.045	[26.472, 47.617]	<0.001∗
	>50 mg	2	1.81	44.70%	0.179	−2.381	[−19.731, 14.968]	0.788
TG (mg/dL)	<50 mg	2	7.67	87.00%	0.006	0.337	[−53.525, 54.200]	0.99
	≥50 mg	1	-	-	-	−3.112	[−40.718, 34.718]	0.876
CRP (ng/mL)	11 mg	1	-	-	-	−5.799	[−8.925, −2.673]	<0.001∗
	45 mg	2	2.11	52.60%	0.146	−10.234	[−20.861, −0.392]	0.039∗
MDA (nmol/mL)	<50 mg	2	10.34	90.30%	0.001	−1.617	[−2.948, −0.286]	0.017∗
	≥50 mg	1	-	-	-	−0.8	[−0.995, −0.605]	<0.001∗

Note. -: values could not be calculated due to an insufficient number of studies; ^∗P < 0.05, and WMD was considered statistically significant.