In their guest blog for IZiNCG, Khov Kuong (DFPTQ, Fisheries Administration, Ministry of Agriculture, Forestry and Fisheries) and Frank Wieringa (the French National Research Institute for Sustainable Development (IRD)) share the findings from the newly published FORSICA project.
Zinc deficiency is highly prevalent in Cambodia. The 2014 Micronutrient Survey in Cambodia found that >60% of the women of reproductive age and under-five children had plasma zinc concentrations <9.9 mmol/L, indicative of zinc deficiency [1]. Other indicators for zinc deficiency, such as stunting prevalence, are highly prevalent too, which the latest Demographic Health Survey (2014) reporting 1 in 3 children being stunted [2]. Although there are few data available, it is likely that zinc status is poor in other age groups in Cambodia, such as in school-aged children.
To improve zinc status of the Cambodian population, the use of zinc-fortified rice is a tempting solution. The consumption of rice in Cambodia is very high, with >60% of daily energy intake coming from rice. Also, zinc-fortified rice is very stable, without zinc being lost over time, or when using different rice cooking techniques [3]. And rice fortified with zinc, iron, and B-vitamins was found to be highly acceptable in Cambodia [4]. Before the start of the FORISCA ((Fortified Rice for School Children in Cambodia) project, we tested the organoleptic qualities of different types of fortified rice on mothers and school teachers. Interestingly, over 80% of the mothers were capable of picking out correctly the fortified rice out of a sample of 3 plates of rice. But the fortified rice scored high on different aspects of organoleptic qualities, such as smell and taste.
As the United Nations World Food Program (WFP) in Cambodia was exploring possibilities to improve nutritional status of school children in Cambodia through use of fortified foods in school meal programs, we took the opportunity to test the impact of introducing fortified rice on micronutrient status, morbidity and cognitive development in school children. Together with the US-based NGO PATH, and co-funded by the United States Department of Agriculture (USDA), WFP-DSM consortium and IRD, we recruited almost 10,000 school children within the FORISCA project. The FORISCA project was developed together with the Government of Cambodia’s Ministry of Education, Youth and Sports, The Ministry of Agriculture, Forestry and Fisheries and the National Fortification Board. The aim of the project was two-fold. First, to test whether a daily breakfast with multiple-micronutrient fortified rice could reduce anemia prevalence, improve micronutrient status and improve functional outcomes such as cognitive development and incidence of infectious diseases. The second aim was to test whether different types of fortified rice (i.e. cold extruded vs hot extruded) had different efficacy in improving micronutrient status. For this aim, 3 different types of fortified rice where tested, with different micronutrient composition and different fabrication techniques.
The micronutrient content of the different fortified rice groups tested in the FORISCA project, per 100 g of uncooked blended rice.
Within the FORISCA project, school children were given a standard breakfast, 6 days per week, for 6 months. The breakfast consisted of rice (~100 g dry rice per child per day), with a sauce of tomatoes, oil (fortified with vitamin A) and fish (~5 g per child per day). Breakfast was prepared every morning in the school kitchen, and meals were distributed over the classes.
Schools were allocated to receive either normal rice, or one of the 3 different types of fortified rice tested. Children would receive their breakfast at 7 in the morning, and class would start thereafter. Children were assessed for anthropometry, cognitive development and micronutrient status at baseline, midline (after 3 months) and at endline.
Baseline micronutrient status confirmed our suspicion that zinc status was poor in school-aged children in Cambodia, with >80% of the school children having low plasma zinc concentrations [5]. Severe zinc deficiency, defined as a plasma zinc concentration <7.6 mmol/L) was present in ~50% of the school children. Six-month consumption of rice fortified with zinc significantly reduced the prevalence of zinc deficiency in the children, with the fortified rice with the highest zinc content, (Nutri-Rice) having the greatest reduction. At endline of the study, the prevalence of zinc deficiency and severe deficiency had not changed in the group receiving ordinary rice, and remained very high at 93% and 54% respectively. In contrast, in the Nutri-Rice group, the prevalence of zinc deficiency and severe zinc deficiency had decreased to 66% and 25% respectively. In the Ultra-Rice Improved group of school children, which was the fortified rice with the lowest fortification level of zinc, the prevalence of zinc deficiency and severe zinc deficiency was reduced too as compared to the placebo group, but to a lesser extent than in the Nutri-Rice group (to 83% and 37% respectively).
We calculated that the zinc fortified rice contributed between 29% (Ultra-Rice improved) and 53% (Nutri-Rice) of the Recommended Daily Allowance (RDA) of the school children over the 6 month intervention period. Clearly, the higher zinc content of the Nutri-Rice contributed to the greater impact on zinc status. But even with ~50% of the RDA covered by the fortified breakfast, 25% of the children remained severely zinc deficient. Given the very high prevalence of zinc deficiency in this population, the amount of zinc in the fortified rice could easily be doubled, to cover 100% of the RDA. Vitamin A status was improved also in the children who received rice fortified with vitamin A, with children in the Ultra-Rice improved and Nutri-Rice groups having a risk for marginal vitamin A status that was 1/5 and 1/4 respectively of children receiving normal rice [6].
The prevalence of anemia in the school children was lower than expected, at 16% [6]. Surprisingly, the prevalence of iron deficiency was very low, with <2% of the children having iron deficiency, and hence, the fortified rice had little impact on anemia prevalence or on improving iron status. Sub-clinical inflammation also played a role here, as in children without inflammation, there was a tendency towards higher haemoglobin concentrations in all the groups receiving fortified rice.
Another surprising outcome of the FORISCA project was the increase in hookworm infection in the children receiving fortified rice. At baseline, all children were dewormed. However, after 6 months, up to 30% of the children were re-infected, and the re-infection rate was higher in the children receiving fortified rice than in the children receiving normal rice[7]. The re-infection rate was highest in the children receiving the fortified rice with the highest iron content, making us believe that the iron in the fortified rice played a role in enabling the re-establishment of the hookworm infection. Also, as hookworm re-infection rate tended to be higher in the cold-extruded fortified rice groups, bioavailability of iron might have been different between the cold- and hot-extruded rice varieties.
Finally, despite the differences in zinc content of the 3 groups of fortified rice, both types of extruded fortified rice (cold vs hot extruded rice) were effective in improving zinc status and therefore production method appears not to be an important factor in determining the impact on zinc status of fortified rice.
The WFP in Cambodia is currently assessing the expanded use of fortified rice in the school meal program, and the aim is to have a rice fortified breakfast for all the children participating in the school meal program, meaning that almost 250,000 children will hopefully receive a fortified rice meal soon.
REFERENCES
1. Wieringa FT, Dahl M, Chamnan C, Poirot E, Kuong K, Sophonneary P, Sinuon M, Greuffeille V, Hong R, Berger J, et al: The High Prevalence of Anemia in Cambodian Children and Women Cannot Be Satisfactorily Explained by Nutritional Deficiencies or Hemoglobin Disorders. Nutrients 2016, 8.
2. Cambodia Demographic and Health Survey 2014. [https://dhsprogram.com/pubs/pdf/FR312/FR312.pdf]
3. Kuong K, Laillou A, Chea C, Chamnan C, Berger J, Wieringa FT: Stability of Vitamin A, Iron and Zinc in Fortified Rice during Storage and Its Impact on Future National Standards and Programs-Case Study in Cambodia. Nutrients 2016, 8.
4. Khanh Van T, Burja K, Thuy Nga T, Kong K, Berger J, Gardner M, Dijkhuizen MA, Hop le T, Tuyen le D, Wieringa FT: Organoleptic qualities and acceptability of fortified rice in two Southeast Asian countries. Ann N Y Acad Sci 2014, 1324:48-54.
5. Kuong K, Tor P, Perignon M, Fiorentino M, Chamnan C, Berger J, Burja K, Dijkhuizen MA, Parker M, Roos N, Wieringa FT: Multi-Micronutrient Fortified Rice Improved Serum Zinc and Folate Concentrations of Cambodian School Children. A Double-Blinded Cluster-Randomized Controlled Trial. Nutrients 2019, 11.
6. Perignon M, Fiorentino M, Kuong K, Dijkhuizen M, Burja K, Parker M, Chamnan C, Berger J, Wieringa FT: Impact of Multi-Micronutrient Fortified Rice on Hemoglobin, Iron and Vitamin A Status of Cambodian Schoolchildren: a Double-Blind Cluster-Randomized Controlled Trial.Nutrients 2016, 8:doi:10.3390/nu8010029.
7. de Gier B, Campos Ponce M, Perignon M, Fiorentino M, Khov K, Chamnan C, de Boer MR, Parker ME, Burja K, Dijkhuizen MA, et al: Micronutrient-Fortified Rice Can Increase Hookworm Infection Risk: A Cluster Randomized Trial. PLoS One 2016, 11:e0145351.