TABLE 6.

Summary of forest plot analyses of the effect of zinc supplementation in infants and children aged ≤3 y on serum/plasma copper concentration (μg/dL), analyzed by duration, chemical formula, and comparator group¹

Group/subgroup	References	Mean difference	95% CI	P	I 2
Children receiving interventions for <3 mo by zinc dose
10.1–20 mg/d	(32)	−16.50	−24.09, −8.91		NA
>20 mg/d	(67)	0.02	−0.41, 0.45		42
Overall		−0.50	−1.90, 0.90	0.48	90
Children receiving interventions for >3 mo by zinc dose
<5 mg/d	(8, 17, 34)	−4.62	−15.01, 5.78		50
5–10 mg/d	(13, 35, 47, 62, 72)	−1.50	−5.10, 2.11		0
10.1–20 mg/d	(30)	−15.50	−18.21, −12.79		NA
Zn bolus2	(28, 33)	−1.03	−4.08, 2.01		0
Overall		−4	−8.82, 0.82	0.10	82
Children receiving zinc through zinc gluconate by zinc dose
5–10 mg/d	(62)	−5.20	−20.16, 9.76		NA
10.1–20 mg/d	(30)	−15.50	−18.21, −12.79		NA
Overall		−13.08	−21.64, −4.53	0.003	43
Children receiving zinc through zinc sulfate by zinc dose
<5 mg/d	(34)	−10.25	−20.18, −0.33		0
5–10 mg/d	(8, 13, 35, 47, 72)	−0.63	−4.26, 2.99		0
10.1–20 mg/d	(32)	−16.50	−24.09, −8.91		NA
Overall		−4.09	−9.31, 1.12	0.12	61
Children receiving zinc through zinc acetate by zinc dose
Zn bolus2	(28,33)	−1.03	−4.08, 2.01		0
Overall		−1.03	−4.08, 2.01	0.51	0
Children receiving zinc vs. placebo by zinc dose
<5 mg/d	(17)	−7.52	−21.69, 6.65		NA
5–10 mg/d	(13, 47, 72)	−1.41	−6.76, 3.93		0
10.1–20 mg/d	(30, 32)	−15.61	−18.17, −13.06		0
>20 mg/d	(67)	0.02	−0.41, 0.45		42
Zn bolus2	(28, 33)	−0.21	−3.52, 3.09		0
Overall		−4.11	−6.48, −1.74	<0.001	94

¹NA, not applicable.

²Bolus doses given as follows: Brooks et al. (33) 21/d mg given weekly; Baqui et al. (28) 20 mg/d once weekly; Bates et al. (18) 70 mg/d twice weekly.