Cochrane · systematic review · CD011302
Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status in populations
Field, MS, Mithra, P, Peña-Rosas, JP · Cochrane Database of Systematic Reviews · 2021 · Cochrane Library
SoF tableOnly the outcomes this review put in its Summary of Findings table are listed (the Cochrane Handbook caps them at about seven per comparison). Its other analyses are not shown here.
Questions
14
current version
GRADE rated
7
No studies
0
Included studies
NR
No studies 0 · 0%Ungraded 7 · 50%Very low 4 · 28.6%Low 1 · 7.1%Moderate 2 · 14.3%High 0 · 0%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
Questions and results
Current version onlyiron‐fortified wheat flour with or without other micronutrients added versus wheat flour (no added iron) with the same other micronutrients added
Population: general population of all age groups (including pregnant women) from any country, over two years of age
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Anaemia (defined as haemoglobin below WHO cut‐off for age and adjusted for altitude as appropriate) iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added | RR 0.73 [0.55, 0.97] | 5 studies · 2315 participants | Low Downgraded: risk of bias, imprecision, indirectness |
Iron deficiency (as defined by study authors, based on a biomarker of iron status) iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added | RR 0.46 [0.2, 1.04] | 3 studies · 748 participants | Very low Downgraded: risk of bias, imprecision, inconsistency |
Haemoglobin concentration (g/L) iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added | no estimate extracted | 8 studies · 2831 participants | Very low Downgraded: risk of bias, inconsistency, indirectness |
Diarrhoea (3 liquid stools in a single day) (only in children 2 to 11 years of age) iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added | no estimate extracted | 0 studies · 0 participants | Ungraded |
Respiratory infections (as measured by trialists) (only in children 2 to 11 years of age) iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added | no estimate extracted | 0 studies · 0 participants | Ungraded |
All‐cause death (only in children 2 to 11 years of age) iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added | no estimate extracted | 0 studies · 0 participants | Ungraded |
Infection or inflammation at individual level as measured by C‐reactive protein (CRP) (only in children 2 to 11 years of age) iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added | no estimate extracted | 2 studies · 558 participants | Moderate Downgraded: risk of bias |
Iron‐fortified wheat flour with other micronutrients added versus unfortified wheat flour (no micronutrients added)
Population: general population of all age groups (including pregnant women) from any country, over two years of age
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Anaemia (defined as haemoglobin below WHO cut‐off for age and adjusted for altitude as appropriate) Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) | RR 0.77 [0.41, 1.46] | 2 studies · 317 participants | Very low Downgraded: risk of bias, imprecision, indirectness |
Iron deficiency (as defined by study authors, based on a biomarker of iron status) Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) | RR 0.73 [0.54, 0.99] | 3 studies · 382 participants | Moderate Downgraded: risk of bias |
Haemoglobin concentration (g/L) Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 4 studies · 532 participants | Very low Downgraded: risk of bias, imprecision, indirectness |
Diarrhoea (3 liquid stools in a single day) (only in children 2 to 11 years of age) Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Respiratory infections (as measured by trialists) (only in children 2 to 11 years of age) Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
All‐cause death (only in children 2 to 11 years of age) Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Infection or inflammation at individual level (as measured by urinary neopterin, C‐reactive protein or alpha‐1‐acid glycoprotein variant A) Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Wheat flour fortified with iron alone compared to unfortified wheat flour (no micronutrients added) for reducing anaemia and improving iron status in populations
Population: s
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Anaemia (defined as haemoglobin below WHO cut‐off for age and adjusted for altitude as appropriate) Wheat flour fortified with iron alone vs unfortified wheat flour (no micronutrients added) | RR 0.81 [0.61, 1.07] | 5 studies · 2200 participants | Low Downgraded: risk of bias |
Iron deficiency (as defined by study authors, based on a biomarker of iron status) Wheat flour fortified with iron alone vs unfortified wheat flour (no micronutrients added) | RR 0.43 [0.17, 1.07] | 3 studies · 633 participants | Moderate Downgraded: risk of bias, imprecision, indirectness |
Haemoglobin concentration (g/L) Wheat flour fortified with iron alone vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 7 studies · 2355 participants | Very low Downgraded: risk of bias, imprecision, indirectness |
Diarrhoea (three liquid stools in a single day) (only in children 2 to 11 years of age) Wheat flour fortified with iron alone vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Respiratory infections (as measured by trialists) (only in children 2 to 11 years of age) Wheat flour fortified with iron alone vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
All‐cause death (only in children 2 to 11 years of age) Wheat flour fortified with iron alone vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Infection or inflammation at individual level as measured by C‐reactive protein (CRP) (only in children 2 to 11 years of age) Wheat flour fortified with iron alone vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 2 studies · 558 participants | Moderate Downgraded: risk of bias, imprecision, indirectness |
Wheat flour fortified with iron in combination with other micronutrients compared to unfortified wheat flour (no micronutrients added) for reducing anaemia and improving iron status in populations
Population: s
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Anaemia (defined as haemoglobin below WHO cut‐off for age and adjusted for altitude as appropriate) Wheat flour fortified with iron in combination with other micronutrients vs unfortified wheat flour (no micronutrients added) | RR 0.95 [0.69, 1.31] | 2 studies · 322 participants | Low Downgraded: risk of bias |
Iron deficiency (as defined by study authors, based on a biomarker of iron status) Wheat flour fortified with iron in combination with other micronutrients vs unfortified wheat flour (no micronutrients added) | RR 0.74 [0.54, 1] | 3 studies · 387 participants | Moderate Downgraded: risk of bias, imprecision, indirectness |
Haemoglobin concentration (g/L) Wheat flour fortified with iron in combination with other micronutrients vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 3 studies · 384 participants | Low Downgraded: risk of bias, imprecision, indirectness |
Diarrhoea (three liquid stools in a single day) (only in children 2 to 11 years of age) Wheat flour fortified with iron in combination with other micronutrients vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Respiratory infections (as measured by trialists) (only in children 2 to 11 years of age) Wheat flour fortified with iron in combination with other micronutrients vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
All‐cause death (only in children 2 to 11 years of age) Wheat flour fortified with iron in combination with other micronutrients vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Infection or inflammation at individual level (as measured by urinary neopterin, C‐reactive protein or alpha‐1‐acid glycoprotein variant A) Wheat flour fortified with iron in combination with other micronutrients vs unfortified wheat flour (no micronutrients added) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Wheat flour fortified with iron in combination with other micronutrients compared to fortified wheat flour with same micronutrients (but not iron) for reducing anaemia and improving iron status in populations
Population: s
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Anaemia (defined as haemoglobin below WHO cut‐off for age and adjusted for altitude as appropriate) Wheat flour fortified with iron in combination with other micronutrients vs fortified wheat flour with same micronutrients (but not iron) | RR 0.24 [0.08, 0.71] | 1 study · 127 participants | Very low Downgraded: risk of bias |
Iron deficiency (as defined by study authors, based on a biomarker of iron status) Wheat flour fortified with iron in combination with other micronutrients vs fortified wheat flour with same micronutrients (but not iron) | RR 0.42 [0.18, 0.97] | 1 study · 127 participants | Very low Downgraded: risk of bias |
Haemoglobin concentration (g/L) Wheat flour fortified with iron in combination with other micronutrients vs fortified wheat flour with same micronutrients (but not iron) | no estimate extracted | 2 studies · 488 participants | Low Downgraded: risk of bias, imprecision, indirectness |
Diarrhoea (three liquid stools in a single day) (only in children 2 to 11 years of age) Wheat flour fortified with iron in combination with other micronutrients vs fortified wheat flour with same micronutrients (but not iron) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Respiratory infections (as measured by trialists) (only in children 2 to 11 years of age) Wheat flour fortified with iron in combination with other micronutrients vs fortified wheat flour with same micronutrients (but not iron) | no estimate extracted | 0 studies · 0 participants | Ungraded |
All‐cause death (only in children 2 to 11 years of age) Wheat flour fortified with iron in combination with other micronutrients vs fortified wheat flour with same micronutrients (but not iron) | no estimate extracted | 0 studies · 0 participants | Ungraded |
Infection or inflammation at individual level (as measured by urinary neopterin, C‐reactive protein or alpha‐1‐acid glycoprotein variant A) Wheat flour fortified with iron in combination with other micronutrients vs fortified wheat flour with same micronutrients (but not iron) | no estimate extracted | 0 studies · 0 participants | Ungraded |