Efficacy of amaranth grain (Amaranthus cruentus) on anaemia and iron deficiency in Kenyan pre-school children

Background
Adding iron rich foods such as amaranth grain flour or micronutrient powders (MNP) containing low doses of highly bioavailable iron (e.g. NaFeEDTA) could be options to control iron deficiency (ID) in pre-school children. However, data evaluating the impact of such food-to-food or in-home fortification strategies is limited. The aim of this thesis was to investigate the effect of consumption of amaranth grain flour on anaemia and iron status of Kenyan pre-school children.
Methods
First a nutrition situation was assessed through a food consumption and nutrition study. We then simulated the potential effect of fortifying maize porridge with amaranth grain flour or MNP on prevalence of inadequate iron intake and ID. Next, an acceptability study was conducted. Factors that would predict the intention of consumption of amaranth porridge among children were identified and the sensory acceptability of amaranth porridge evaluated. Finally, a controlled, randomized 16-weeks intervention trial was conducted (n=279; aged 12-59 months) to determine the efficacy of maize porridge enriched with amaranth grain flour or MNP in form of NaFeEDTA. Primary outcome was anaemia and iron status with treatment effects estimated relative to control group receiving maize porridge only.
Results
The nutrition situation assessment showed that there were deficits in dietary energy, iron and zinc with early introduction of complementary foods. The simulation estimates resulted in a significant increase (P<0.005) in ferritin concentration in amaranth (1.82µg/L: CI 1.42-2.34) and MNP (1.80µg/L: CI 1.40-2.31) group compared to maize porridge group decreasing the prevalence ID to 27% in both groups.
In the acceptability study, knowledge and health value significantly predicted health behaviour identity. None of the models significantly predicted intention. A significant preference for the unfermented amaranth enriched maize porridge compared to the fermented porridge was observed. There was no difference in preference of the 50:50 and 70:30 (amaranth to maize) unfermented porridges.
Baseline prevalence of stunting was (48.2%), anaemia (38%), ID (30%) and iron deficiency anaemia (IDA, 22%) in the clinical trial. Though consumption of amaranth grain porridge reduced anaemia, ID and IDA prevalence compared to control group, this reduction was not significant. Consumption of MNP porridge significantly reduced the prevalence of anaemia by 46% (CI: -67% to -12%), ID by 70% (CI:-89% to -16%) and IDA by 75% (CI: -92% to -20%) compared to control group. MNP porridge significantly increased haemoglobin by 2.7g/L (CI: 0.4 to 5.1) and ferritin (40% CI: 10% to 95%), and decreased TfR by 10% (CI:-16% to -4%) concentration.
Conclusion
Addition of amaranth grain flour to maize porridge even when shown to have high iron content did not significantly reduce the prevalence of IDA in pre-school children. In contrast, consumption of maize porridge fortified with 2.5mg of NaFeEDTA can reduce the prevalence of IDA in children. Absorption studies for amaranth grain should be conducted before its public health promotion in dietary diversification as a source of iron is accelerated. Research to assess the safety of bolus doses of MNP formulated with NaFeEDTA and optimal dosing schedule is also needed. Furthermore, the effectiveness of both amaranth grain flour and MNP should be further evaluated in large scale programs.