The impact of Quality Protein Maize (QPM) on school children’s weight and height: Results from an effectiveness trial in Colombia
The impact of Quality Protein Maize (QPM) on school children’s weight and height: Results from an effectiveness trial in Colombia Helena Pachón1, Sayda Milena Pico Fonseca1, Jorge E. Gómez2 , Freddy Escobar Pinto11 Centro Internacional de Agricultura Tropical (CIAT), Colombia 2 Independent consultant, Colombia
Introduction Biofortification is the process of increasing the nutrient concentration of staple crops . One of the first biofortified crops was Quality Protein Maize (QPM). Due to a naturally occurring mutation, Q has a g , QPM greater concentration than common maize (CM) of lysine and tryptophan, Photo: Catherine Bermudez Kandianis two of the limiting amino acids in cereals . l 2 Nestel P, Bouis HE, Meenakshi JV, Pfeiffer W. Biofortification of staple food crops. J Nutr, 136:1064–1067, 2006. 136:1064 1067, Mertz ET, Bates LS, Nelson OE. Mutant gene that changes protein composition and increases lysine content of maizeendosperm. Science, 145:279-280, 1964.
QPM: More Amino Acids inEndosperm http://www.nativeaccess.com/ancestral/corn/summer.html
Amino Acid ConcentrationLysine and Tryptophan Levels as a Percentage of Total Protein in Whole d h l f l h lGrain Flour of Normal and QPM, and FAO Requirements for ChildrenSource: Krivanek et al., 2007
Same Digestibility Coupled with p higher tryptophan (and lysine) levels, this suggests gg greater uptake of the amino acids by the human body Imbachí-Narvaez et al., 2010
Introduction Compared with CM, QPM, or its predecessor, opaque-2 maize, improves by 10% the weight and height of mildly to moderately malnourished preschool children . The nutritional impact of QPM in school-age children has never been studied studied. Gunaratna NS, De Groote H, Nestel P, Pixley KV, McCabe GP. A meta-analysis of community based studies on quality proteinmaize. Food Policy. 35(3):202-210, 2010.
Objective Evaluate the impact on school children’s weight and height of consuming QPM through a government-supported school- feeding program.Photo: Neil Palmer
Methods Ethical approval was received from the Universidad de f h U i id d d Antioquia in Colombia. A multi-stage process was followed to identify schools and children to participate in the study from a rural, predominantly indigenous municipality in southwestern Colombia. Photo: Neil Palmer
Intervention There were three intervention groups; the intervention was at the school level level. In a quasi-experimental design, schools were assigned to receive QPM seed (SEED) for planting (n=4), QPM for consuming (n 3), (n=3), or CM for consuming (n=5). (n 5). Selection into the SEED group was by convenience; these schools were beneficiaries of two government feeding programs. Among the remaining 8 schools, assignation into the QPM or CM schools consumption groups was random; these schools were beneficiaries of one government program. In the consumption schools, all children in the school received the schools assigned maize during the school-feeding program. Only a subset of these children were measured at baseline and endline.
Intervention For 12 mo, QPM and CM groups received sufficient maize for all i d ffi i t i f ll children in the school to consume 35 g/school d and during vacation, 35 g/family member/d. The SEED group received 3 kg of QPM seed to produce ~600 kg of maize. Distribution of maize for consumption began in September 2009. Insufficient water due to a prolonged dry season i 2009 resulted in crop in l di failure for 3 of the 4 SEED schools. Photo: Neil Palmer
Measurements Enumerators, blind to the schools schools’ intervention group, group measured children’s weight to the nearest 0.1 kg and height to the nearest 0.1 cm at baseline and endline. Z scores were calculated using WHO AnthroPlus v1.0.1. At baseline, children’s parents were surveyed about sociodemographics, food security, diet and other characteristics.
Measurements Milled maize, as provided to the schools and families, was periodically analyzed for tryptophan, which is highly correlated with lysine concentration . At h h l h A the schools, the amount of maize- containing foods served to and consumed b children d d by h ld was measured near baseline and endline. Vivek BS, Krivanek AF, Palacios-Rojas N, Twumasi-Afriyie S, Diallo AO. Breeding Quality Protein Maize(QPM): Protocols for developing QPM cultivars. Mexico: CIMMYT, 2008.
Baseline Characteristics At baseline, there were differences among the intervention groups i child gender, age, i di i i in hild d indigenous or not, school grade and height (P<0.05). The groups were similar with respect to child weight weight, having consumed animal-source foods in the past 7 d, appetite in the past mo, household socioeconomic strata, the relationship between number who work and number who live in the household, number of household assets, household food security, and the time needed to travel to the closest health unit (P>0.05). At baseline, 33.7% of the children were stunted (height- for-age Z <-2).
Impact on Children’s Weight & Height Children gained 2-3 kg and ~6 cm during the study, regardless of the intervention group. Using an intention-to-treat analysis, these results did not change after adjusting for the cluster design and covariates covariates. Weight (kg) Height (cm)InterventionGroup (n) Baseline Endline Difference* Baseline Endline Difference*SEED (n=119)CM (n=75)QPM (n=80)* Different letters in the difference column signal statistically significant differences (P<0.05)
Discussion Contrary to expectations, expectations the three intervention groups had similar weight and h i ht i ht d height gains. Several questions q were explored to identify the reason(s) for these findings. g Photo: Neil Palmer
Did the children have the potential torespond to the intervention? d t th i t ti ? Yes, 33.7% had low height-for-age at baseline and children grew 2- 3 kg and 6 cm during this period period. Photo: Neil Palmer
Was the intervention delivered daily to the hild ? th children? No, schools provided maize 21-89% of the academic year. Intervention School Days school in Days maize served, Group session session*, n (%) n (%) 1 QPM 2 3 1 2† CM 3 4† 5* Schools closed due to teacher strikes, inclement weather or cultural events.† Estimates provided by food preparers in schools as notebooks with this information were lost or stolen.
Was the intervention delivered differentially based on intervention group? b d i t ti ? Yes, CM schools served maize on average 13.5 d more than QPM schools. schools Intervention School Days school in Days maize served, n (%) Group session session*, n (%) 1 QPM 2 3 1 2† CM 3 4† 5* Schools closed due to teacher strikes, inclement weather or cultural events.† Estimates provided by food preparers in schools as notebooks with this information were lost or stolen.
Did children consume 35 g/d of maizeat school? t h l? No, they consumed between 16-110 g/d.Intervention School Recipe Children, n Maize consumed group (g), mean (SD) 1 Mazamorra QPM 2 Mazamorra 3 Mazamorra 1 Mazamorra 1 Masitas CM 2 Mazamorra 3 p Maize soup 4 Maize soup 1 Mazamorra 2 Mazamorra SEED 3 Mazamorra 4 Mazamorra
Was the quantity of maize consumed different based on intervention group? diff tb d i t ti g ? Yes, CM schools served ~3 times more maize than QPM schools.Intervention School Recipe Children, n Maize consumed (g), mean (SD) group 1 Mazamorra QPM 2 Mazamorra 3 Mazamorra 1 Mazamorra 1 Masitas CM 2 Mazamorra 3 p Maize soup 4 Maize soup 1 Mazamorra 2 Mazamorra SEED 3 Mazamorra 4 Mazamorra
Was there more tryptophan in the QPMthanth CM? Yes, 28% more. Tryptophan Levels: Mean + SD Milled QPM Milled CM
Was this difference observed in previous studies that obtained nutritional impact of QPM? No, >42% differences in tryptophan concentration between CM and QPM were observed in other studies [5 8] [5-8]. Photo: Neil Palmer Graham GG, Lembcke J, Lancho E Morales E Quality protein maize: Digestibility and utilization by GG J E, E.recovering malnourished infants. Pediatrics, 83:416-421, 1989. Akuamoa-Boateng A. Quality protein maize infant feeding trials in Ghana. Ghana: Ghana Health Service,2002. Ortega Alemán EdC, Coulson Romero AJ, Ordóñez Argueta LI, Pachón H. Efectos de la ingesta de maízde alta calidad de proteína (QPM) versus maíz convencional en el crecimiento y la morbilidad de niñosnicaragüenses d i ü desnutridos d 1 a 5 años d edad. A h L ti t id de ñ de d d Arch Latinoamer N t 58(4) 377 385 2008. Nutr, 58(4):377-385, 2008 Morales Guerra M. Efecto del consumo de maíz de alta calidad proteínica en niño(a)s de familiasindígenas de las regiones Mazateca y Mixe del estado de Oaxaca: Una estrategia agronómica de desarrolloentre campesinos que practican agricultura de subsistencia. PhD Thesis. Mexico: Institución de Enseñanza eInvestigación en Ciencias Agrícolas, 2002.
ConclusionUnder real-life conditions, QPMdid not improve school children’snutritional status. This could be dueto the intervention not beingdelivered as planned in a school-feeding program, with respect tothe amino acid concentration in themilled maize, the number of days itwas served to children, and the childrenquantity offered. Photo: Neil Palmer
Acknowledgements Edgar Burbano, Marlene Rosero, Jacinto Azcárate Data-collection teams CIAT’s N CIAT’ Nutrition Q l Quality Laboratory Participating schools schools, principals, parents and children Municipal and departmental p p government agencies Funding provided by the AgroSalud Project (CIDA 7034161) Photo: Neil Palmer
Video http://www.youtube.com/watch?v=w5oyFBqobpM; Neil Palmer