Table 6 Summary of results for multiple micronutrient fortification in children
From: Micronutrient fortification of food and its impact on woman and child health: a systematic review
Outcome/quality of evidence | Combined effect | Â | Age groups | Country | Number of micronutrients used | Duration of fortification | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
General/healthy population | Deficient population | Infants | Preschool and school-going children | Low- and lower middle-income countries | Upper middle- and higher-income countries | 5 or less | 6 to 12 | More than 12 | Less than 6 months | 6 to 11 months | 12 months or more | ||
Hemoglobin levels | SMD: 0.75 (95% CI: 0.41, 1.08) | SMD: 0.72 (95% CI: 0.37, 1.07) | SMD: 1.06 (95% CI: 0.75, 1.38) | SMD: 1.05 (95% CI: 0.48, 1.63) | SMD: 0.45 (95% CI: 0.12, 0.79) | SMD: 0.50 (95% CI: 0.21, 0.78) | SMD: 1.25 (95% CI: 0.45, 2.06) | SMD: 1.50 (95% CI: -0.23, 3.23) | SMD: 0.51 (95% CI: 0.24, 0.78) | SMD: 0.71 (95% CI: 0.32, 1.09) | SMD: 0.07 (95% CI: -0.17, 0.31) | SMD: 1.05 (95% CI: 0.55, 1.56) | SMD: 0.52 (95% CI: 0.07, 0.98) |
Quality of evidence: Moderate | Â | 13 studies 2,876 participants | 1 study 175 participants | 7 studies 1,508 participants | 7 studies 1,543 participants | 8 studies 1,769 participants | 6 studies 1,282 participants | 4 studies 747 participants | 6 studies 1,449 participants | 4 studies 855 participants | 2 studies 310 participants | 8 studies 2,025 participants | 4 studies 716 participants |
Serum ferritin levels | SMD: 0.37 [0.13, 0.62) | SMD: 0.37 (95% CI: 0.13, 0.62) | No studies identified | SMD: 0.43 (95% CI: 0.17, 0.68) | SMD: 0.06 (95% CI: -0.17, 0.29) | SMD: 0.47 (95% CI: 0.14, 0.80) | SMD: 0.18 (95% CI: -0.03, 0.40) | SMD: 0.45 (95% CI: 0.00, 0.90) | SMD: 0.62 (95% CI: 0.18, 1.06) | SMD: 0.17 (95% CI: -0.16, 0.50) | SMD: 0.45 (95% CI: 0.00, 0.90) | SMD: 0.48 (95% CI: 0.07, 0.89) | SMD: 0.20 (95% CI: -0.23, 0.64) |
Quality of evidence: Low | Â | 7 studies 1,848 participants | Â | 6 studies 1,547 participants | 1 study 301 participants | 4 studies 1,380 participants | 3 studies 468 participants | 1 study 79 participants | 2 studies 748 participants | 4 studies 1,021 participants | 1 study 79 participants | 3 studies 1,049 participants | 3 studies 7,20 participants |
Serum zinc levels | SMD: 0.08 [−0.02, 0.19) | SMD: 0.08 (95% CI: -0.02, 0.19) | No studies identified | SMD: 0.04 (95% CI: -0.10, 0.17) | SMD: 0.17 (95% CI: 0.04, 0.30) | SMD: 0.12 (95% CI: 0.01, 0.23) | SMD: -0.02 (95% CI: -0.26, 0.23) | SMD: -0.12 (95% CI: -0.75, 0.51) | SMD: 0.13 (95% CI: -0.02, 0.29) | SMD: 0.06 (95% CI: -0.05, 0.17) | SMD: 0.31 (95% CI: 0.06, 0.57) | SMD: 0.06 (95% CI: -0.09, 0.21) | SMD: 0.02 (95% CI: -0.11, 0.15) |
Quality of evidence: Moderate | Â | 11 studies 2,972 participants | Â | 7 studies 1,780 participants | 4 studies 1,192 participants | 7 studies 1,960 participants | 4 studies 1,012 participants | 2 studies 232 participants | 4 studies 1,820 participants | 5 studies 920 participants | 1 study 223 children | 6 studies 1,128 participants | 4 studies 1,221 participants |
Serum retinol levels | SMD: -0.05 [−0.23, 0.13) | SMD: 0.05 (95% CI: -0.23, 0.13) | No studies identified | SMD: 0.04 (95% CI: -0.22, 0.30) | SMD: -0.21 (95% CI: -0.34, -0.07) | SMD: -0.06 (95% CI: -0.25, 0.14) | SMD: 0.01 (95% CI: -0.63, 0.64) | SMD: -0.28 (95% CI: -0.45, -0.11) | SMD: -0.03 (95% CI: -0.33, 0.27) | SMD: 0.02 (95% CI: -0.27, 0.31) | No studies identified | SMD: -0.08 (95% CI: -0.29, 0.13) | SMD: 0.03 (95% CI: -0.37, 0.43) |
Quality of evidence: Low | Â | 8 studies 1,927 participants | Â | 4 studies 964 participants | 4 studies 963 participants | 6 studies 1,320 participants | to 2 studies 607 participants | 2 studies 533 participants | 5 studies 878 participants | 3 studies 516 participants | Â | 3 studies 1,676 participants | 3 studies 251 participants |
Effect on anemia | RR: 0.55 (95% CI: 0.42, 0.71) | RR: 0.59 (95% CI: 0.46, 0.75) | RR: 0.20 (95% CI: 0.10, 0.40) | RR: 0.59 (95% CI: 0.50, 0.70) | RR: 0.45 (95% CI: 0.22, 0.89) | RR: 0.50 (95% CI: 0.37, 0.67) | RR: 0.69 (95% CI: 0.41, 1.15) | No studies identified | No studies identified | No studies identified | RR: 0.77 (95% CI: 0.43, 1.36) | RR: 0.54 (95% CI: 0.36, 0.83) | RR: 0.50 (95% CI: 0.33, 0.77) |
Quality of evidence: Low | Â | 9 studies 2,880 participants | 1 study 175 participants | 5 studies 1809 participants | 5 studies 1246 participants | 7 studies 2,229 participants | 3 studies 826 participants | Â | Â | Â | 1 study 223 children | 4 studies 1,097 participants | 5 studies 1,726 participants |
Effect on vitamin A deficiency | RR: 0.90 (95% CI: 0.76, 1.06) | RR: 0.90 (95% CI: 0.76, 1.06) | No studies identified | RR: 0.85 (95% CI: 0.69, 1.03) | RR: 1.02 (95% CI: 0.76, 1.38) | RR: 0.88 (95% CI: 0.73, 1.07) | RR: 0.95 (95% CI: 0.66, 1.36) | No studies identified | No studies identified | No studies identified | No studies identified | RR: 0.85 (95% CI: 0.71, 1.03) | RR: 1.14 (95% CI: 0.76, 1.71) |
Quality of evidence: Low | Â | 6 studies 2,036 participants | Â | 3 studies 687 participants | 3 studies 1349 participants | 4 studies 1,391 participants | 2 studies 645 participants | Â | Â | Â | Â | 3 studies 1,308 participants | 3 studies 728 participants |
Height-for-age Z-score | SMD: 0.13 (95% CI: -0.04, 0.29) | SMD: 0.12 (95% CI: -0.09, 0.32) | SMD: 0.22 (95% CI: -0.04, 0.47) | SMD: 0.26 (95% CI: 0.12, 0.40) | SMD: -0.01 (95% CI: -0.21, 0.20) | SMD: 0.09 (95% CI: -0.17, 0.34) | SMD: 0.18 (95% CI: 0.02, 0.34) | SMD: -0.00 (95% CI: -0.19, 0.18) | SMD: 0.11 (95% CI: -0.12, 0.34) | SMD: 0.18 (95% CI: -0.07, 0.42) | SMD: 0.01 (95% CI: -0.13, 0.15) | SMD: 0.11 (95% CI: -0.12, 0.34) | SMD: 0.39 (95% CI: 0.24, 0.55) |
Quality of evidence: Low | Â | 6 studies 1,853 participants | 2 studies 245 participants | 5 studies 1,083 participants | 3 studies 1,009 participants | 5 studies 1,485 participants | 3 studies 607 participants | 2 studies 624 participants | 1 study 288 participants | 5 studies 1,180 participants | 5 studies 1,170 participants | 1 study 288 participants | 2 studies 634 participants |
Weight-for-age Z-score | SMD: -0.12 (95% CI: -0.43, 0.20) | SMD: 0.05 (95% CI: -0.09, 0.18) | SMD: 0.18 (95% CI: -0.14, 0.49) | SMD: -0.28 (95% CI: -0.85, 0.29) | SMD: 0.09 (95% CI: -0.16, 0.33) | SMD: 0.10 (95% CI: -0.13, 0.32) | SMD: -0.48 (95% CI: -1.45, 0.49) | SMD: -0.02 (95% CI: -0.28, 0.24) | SMD: -0.03 (95% CI: -0.26, 0.20) | SMD: -0.22 (95% CI: -0.76, 0.33) | SMD: -0.25 (95% CI: -0.90, 0.41) | SMD: 0.06 (95% CI: -0.09, 0.21) | SMD: -0.68 (95% CI: -2.79, 1.42) |
Quality of evidence: Low | Â | 6 studies 1,853 participants | 2 studies 245 participants | 5 studies 1083 participants | 3 studies 1,009 participants | 5 studies 1,485 participants | 3 studies 607 participants | 2 studies 624 participants | 1 study 288 participants | 5 studies 1,180 participants | 5 studies 1,170 participants | 1 study 288 participants | 2 studies 634 participants |
Weight-for-height Z-score | SMD: -0.11 (95% CI: -0.40, 0.17) | SMD: -0.17 (95% CI: -0.56, 0.22) | SMD: -0.56 (95% CI: -1.42, 0.31) | SMD: 0.08 (95% CI: -0.06, 0.21) | SMD: -0.39 (95% CI: -1.06, 0.28) | SMD: 0.07 (95% CI: -0.07, 0.20) | SMD: -0.40 (95% CI: -1.17, 0.38) | SMD: -0.01 (95% CI: -0.29, 0.26) | SMD: -0.14 (95% CI: -0.37, 0.09) | SMD: -0.16 (95% CI: -0.66, 0.34) | SMD: -0.10 (95% CI: -0.75, 0.56) | SMD: -0.23 (95% CI: -0.64, 0.18) | SMD: 0.18 (95% CI: 0.02, 0.34) |
Quality of evidence: Low | Â | 6 studies 1,853 participants | 2 studies 245 participants | 5 studies 1,083 participants | 3 studies 1,009 participants | 5 studies 1,485 participants | 3 studies 607 participants | 2 studies 624 participants | 1 study 288 participants | 5 studies 1,180 participants | 5 studies 1,170 participants | 1 study 288 participants | 2 studies 634 participants |