Table 3.
Low-performing studies of the efficacy of iron fortification of condiments. Impact on hemoglobin, anemia, and iron status.
| Category from Table 2 | Study/Objective/Country/Duration and Experimental Design/Subjects | Condiment/ Fe Source/Concentration |
Iron Intervention Outcomes (Hemoglobin, Anemia Prevalence, and Ferritin) | Suggested Possible Causes (Low-Performing Factors) |
|---|---|---|---|---|
| Did not increase hemoglobin significantly (children) | Kumar et al., 2014 [35] Establish the efficacy of multi-micronutrient fortified salt in addressing multiple micronutrient deficiencies among children compared to nutrition education and no intervention. India 8 mo RCT 528 children (5–15 y) |
Multiple micronutrient fortified salt (iron, iodine, vitamin A, vitamin B12, and folic acid) Chelated FS 1 mg Fe/g salt |
Hb (+0.5 g/dL, NS) Anemia prevalence (−13.4% *) Ferritin (+10.8 * μg/L) |
Insignificant hemoglobin increase was not addressed by authors |
| Did not increase hemoglobin significantly (children) Did not decrease anemia significantly (children) |
Wegmueller et al., 2006 [30] Test efficacy of DFS Cote d’Ivoire 6 mo, double-blind efficacy trial 123 iron-deficient children (5–15 y) |
DFS Micronized ground FePP 3 mg Fe/g salt |
No change in Hb (0 g/dL) Anemia prevalence (+5%, NS) Ferritin increased (+15 * μg/L) |
High prevalence of malaria (55%) and multiple micronutrient deficiencies (B2 deficiency 66%). Up to 52% of households reported darkening of food |
| Did not increase hemoglobin significantly (children) Did not increase ferritin significantly (children) |
Winichagoon et al., 2006 [39] Assess the efficacy of a micronutrient-fortified seasoning powder served with a school lunch on reducing anemia and improving the micronutrient status of children Thailand 31 wk RCT 569 children (5.5–13.4 y) |
Seasoning powder (zinc, iron, vitamin A, and iodine) H-reduced elemental iron encapsulated with partially hydrogenated vegetable oil 5 mg Fe/pouch |
No significant change in Hb (+0.31 g/dL, NS) Anemia prevalence NA No significant change in Ferritin (−11.5 μg/L, NS) |
Insufficient content (5 mg/serving) and form of iron used in the intervention (Reduced elemental Fe) |
| Did not increase hemoglobin significantly (women) | Nair et al., 2014 [25] Test efficacy of DFS with nutrition education on pregnant, anemic mothers India 2 mo RCT 135 pregnant, anemic women |
DFS Fe source NA 1 mg Fe/g salt |
Hb change before and after intervention: −0.15 g/dL (NS) Anemia prevalence NA Ferritin NA |
Not enough Fe intake to meet pregnancy needs during only 2 mo of intervention |
| Did not decrease anemia significantly (children) | Reddy et al., 2014 [27] To assess the impact of DFS on iron and iodine status of schoolchildren. India 9 mo longitudinal intervention study 947 schoolchildren (6–15 y) |
DFS Source NA Concentration NA |
Hb (+0.6 * g/dL and 0.21 * g/dL, deworming and not) Anemia prevalence (−6.3% * and +1.5%, deworming and not) Ferritin NA |
Absence of deworming |
| Did not decrease anemia significantly (women) | Asibey-Berko et al., 2007 [22] Test efficacy of DFS on anemia and iodine deficiency in women and children Ghana 8 mo RCT 300 NP, NL women (15–45 y) and 157 children (1–5 y) |
DFS/ FF/ 1 mg Fe/g salt |
No Hb post-treatment data Anemia prevalence: Children: −21.7% * Women: +3.3% Ferritin NA |
Significant increase of anemia in the control group. Uneven baseline prevalence of anemia. Darker color of DFS. Women reported the darkening of plantains when frying |
| Did not decrease anemia significantly (women) | Haas et al., 2014 [24] Test efficacy of DFS in reducing ID in WRA India 7.5–9 mo RCT 212 NP women (18–55 y) |
DFS Micro-encapsulated FF 1.1 mg Fe/g salt |
Hb (+0.24 * g/dL) Anemia prevalence (+1%) Ferritin (+0.13 * log10 μg/mL), 34% increase. |
High prevalence of folate and B12 deficiencies. High prevalence of elevated MCV (25%) |
| Did not decrease anemia significantly (women) | Reddy et al., 2016 [28] Assess the impact of DFS on iron and iodine status of pregnant women. India 9 mo RCT 150 pregnant women (<12 weeks gestation) |
DFS Ferrous sulfate 1000 ppm at 10 g/day |
Hb (+0.42 * g/dL) Anemia prevalence (−10.5%) Ferritin NA |
Significance of anemia not addressed by authors |
| Did not increase ferritin significantly (children) | Vinodkumar et al., 2009, Int. J Vit Nut Res [37] Test efficacy of multiple micronutrient fortified salt on children India 9 mo RCT 402 children (5–18 y) |
Multiple micronutrient fortified salt (vitamins A, B1, B2, B6, B12, folic acid, niacin, iron, iodine, and zinc) Chelated FS 1 mg Fe/g salt |
Hb increased (+0.67 * g/dL) Anemia prevalence decreased (−40% *) No change in Ferritin (−0.12 μg/L) NS |
Uneven prevalence of anemia and ferritin levels at baseline. Possible adverse interaction with zinc absorption |
Notes: DFS—double-fortified salt; FePP—ferric pyrophosphate; FF—ferrous fumarate; EFF—encapsulated FF; FS—ferrous sulfate; Hb—hemoglobin; ID—iron deficiency; mo—month; NA—data or information not available or unknown; NP—non-pregnant; NL—non-lactating; RCT—randomized control trial; wk—week; WRA—women of reproductive age; y—year. * Indicates statistically significant outcome.