Application of stable isotope dilution techniques to assess body fat and comparison with WHO BMI-for-age classification as a measure of obesity among schoolchildren in Nairobi, Kenya.

OBJECTIVE: WHO BMI-for-age z score (BAZ) is widely used in epidemiology, yet it does not distinguish body fat-free mass and fat mass which are better indicators of obesity and related risks. The stable isotope dilution techniques (SIDT) are gold standard methods of assessing body composition. Main objective was to assess significant differences in measurement and validity of WHO BMI-for-age classification for defining childhood obesity by comparing with body fatness using SIDT among schoolchildren. DESIGN: A cross-sectional analytical study. A questionnaire, anthropometry and body composition data were used. SPSS was used to analyse data at P < 0·05 at 95 % CI. SETTING: Primary schools in Nairobi City County, Kenya. PARTICIPANTS: One hundred seventy-nine schoolchildren aged 8-11 years were randomly sampled. RESULTS: Prevalence of adiposity by reference SIDT (24·0 %) was significantly higher than that of obesity by BAZ > 2 sd (2·8 %) (Wilcoxon test, P < 0·05). Concordance coefficient between SIDT and BAZ > 2 sd in diagnosing obesity was poor (κ = 0·167). Only 11·6 % of children with excess body fat were correctly diagnosed as obese by BAZ > 2 sd. The use of BAZ > 1 sd for overweight and obesity showed fair concordance coefficient (κ = 0·409, P < 0·001) with 32·5% of children with excess fat positively identified as overweight and obese. CONCLUSION: WHO BMI-for-age cut-off points severely underestimate the prevalence of overweight and obesity compared with body composition assessment by stable isotope dilution techniques. Evidence-informed interventions should be based on more accurate estimates of overweight and obesity than that can be provided by BAZ.

Inventory on the dietary assessment tools available and needed in africa: a prerequisite for setting up a common methodological research infrastructure for nutritional surveillance, research, and prevention of diet-related non-communicable diseases.

OBJECTIVE: To carry out an inventory on the availability, challenges, and needs of dietary assessment (DA) methods in Africa as a pre-requisite to provide evidence, and set directions (strategies) for implementing common dietary methods and support web-research infrastructure across countries. METHODS: The inventory was performed within the framework of the "Africa's Study on Physical Activity and Dietary Assessment Methods" (AS-PADAM) project. It involves international institutional and African networks. An inventory questionnaire was developed and disseminated through the networks. Eighteen countries responded to the dietary inventory questionnaire. RESULTS: Various DA tools were reported in Africa; 24-Hour Dietary Recall and Food Frequency Questionnaire were the most commonly used tools. Few tools were validated and tested for reliability. Face-to-face interview was the common method of administration. No computerized software or other new (web) technologies were reported. No tools were standardized across countries. CONCLUSIONS: The lack of comparable DA methods across represented countries is a major obstacle to implement comprehensive and joint nutrition-related programmes for surveillance, programme evaluation, research, and prevention. There is a need to develop new or adapt existing DA methods across countries by employing related research infrastructure that has been validated and standardized in other settings, with the view to standardizing methods for wider use.

Simulation of the effect of maize porridge fortified with grain amaranth or micronutrient powder containing NaFeEDTA on iron intake and status in Kenyan children.

OBJECTIVE: Simulating the probable impact of grain amaranth and highly absorbable, low-Fe micronutrient powder (MNP) on Fe status in a potential target population is an essential step in choosing and developing an appropriate actual intervention. DESIGN: We simulated the potential effect of fortifying maize porridge with grain amaranth or MNP on the prevalence of inadequate Fe intake and Fe deficiency using data from two cross-sectional surveys. In the first survey (2008), dietary intake data were collected by two 24 h recalls (n 197). Biochemical data (n 70) were collected in the second survey (2010). A simulation with daily consumption for 80 d of non-fortified maize porridge (60 g of maize flour), amaranth-enriched porridge (80 g of grain amaranth­maize flour, 70:30 ratio) or maize porridge fortified with MNP (2.5mg Fe as NaFeEDTA) was done. SETTING: Mwingi District, Kenya. SUBJECTS: Pre-school children aged 12­23 months. RESULTS: Prevalence of anaemia, Fe deficiency and Fe-deficiency anaemia was 49 %, 46% and 24 %, respectively. Consumption of non-fortified, amaranth-enriched and MNP-fortified maize porridge was estimated to provide a median daily Fe intake of 8.6 mg, 17.5mg and 11.1 mg, respectively. The prevalence of inadequate Fe intake was reduced to 35% in the amaranth-enriched porridge group and 45% in the MNP-fortified porridge group, while ferritin concentration was increased in both (by 1.82 (95% CI 1.42, 2.34) mg/l and 1.80 (95% CI 1.40, 2.31) µg/l, respectively; P,0.005) compared with the non-fortified maize porridge group, resulting in a decreased prevalence of Fe deficiency (27 %) in the two fortification groups. CONCLUSIONS: Addition of grain amaranth or low-Fe MNP to maize-based porridge has potential to improve Fe intake and status in pre-school children.

Maize porridge enriched with a micronutrient powder containing low-dose iron as NaFeEDTA but not amaranth grain flour reduces anemia and iron deficiency in Kenyan preschool children.

Few studies have evaluated the impact of fortification with iron-rich foods such as amaranth grain and multi-micronutrient powder (MNP) containing low doses of highly bioavailable iron to control iron deficiency anemia (IDA) in children. We assessed the efficacy of maize porridge enriched with amaranth grain or MNP to reduce IDA in Kenyan preschool children. In a 16-wk intervention trial, children (n = 279; 12-59 mo) were randomly assigned to: unrefined maize porridge (control; 4.1 mg of iron/meal; phytate:iron molar ratio 5:1); unrefined maize (30%) and amaranth grain (70%) porridge (amaranth group; 23 mg of iron/meal; phytate:iron molar ratio 3:1); or unrefined maize porridge with MNP (MNP group; 6.6 mg iron/meal; phytate:iron molar ratio 2.6:1; 2.5 mg iron as NaFeEDTA). Primary outcomes were anemia and iron status with treatment effects estimated relative to control. At baseline, 38% were anemic and 30% iron deficient. Consumption of MNP reduced the prevalence of anemia [-46% (95% CI: -67, -12)], iron deficiency [-70% (95% CI: -89, -16)], and IDA [-75% (95% CI: -92, -20)]. The soluble transferrin receptor [-10% (95% CI: -16, -4)] concentration was lower, whereas the hemoglobin (Hb) [2.7 g/L (95% CI: 0.4, 5.1)] and plasma ferritin [40% (95% CI: 10, 95)] concentrations increased in the MNP group. There was no significant change in Hb or iron status in the amaranth group. Consumption of maize porridge fortified with low-dose, highly bioavailable iron MNP can reduce the prevalence of IDA in preschool children. In contrast, fortification with amaranth grain did not improve iron status despite a large increase in iron intake, likely due to high ratio of phytic acid:iron in the meal.

Sensory acceptability and factors predicting the consumption of grain amaranth in Kenya.

This study investigated the effect of adding grain amaranth flour on sensory acceptability of maize porridge in Kenya. Factors influencing the intention of mothers to feed their children on grain amaranth were identified. A significant difference between the various porridge ratios (50:50, 70:30, and 100:0 amaranth:maize) either in unfermented or fermented form could be detected. Preference for the unfermented amaranth enriched maize porridge was observed. Intention significantly correlated and predicted grain amaranth consumption (p < .001). Knowledge and health value significantly predicted health behavior identity. Interaction between barriers and intention negatively influenced behavior. Findings suggest that unfermented amaranth enriched maize porridge is acceptable. Unfermented porridge with 70% amaranth can be considered for use in a program aimed at increasing dietary iron intake among children. Increasing awareness about micronutrient deficiencies and nutritional benefits of grain amaranth could enhance its consumption.

Coverage and Consumption of Micronutrient Powders, Fortified Staples, and Iodized Salt Among Children Aged 6 to 23 Months in Selected Neighborhoods of Nairobi County, Kenya.

BACKGROUND: Intake of micronutrient-rich foods among children aged 6 to 23 months in Nairobi is low. OBJECTIVE: This study aimed to assess existing coverage and utilization of micronutrient powders (MNPs), fortified staples, and iodized salt among children aged 6 to 23 months prior to implementation of an MNP program. METHODS: A cross-sectional survey among caregivers of children aged 6 to 23 months (n = 618) was implemented in 7 neighborhoods within Nairobi County, representing the implementation area of the new MNP program. RESULTS: Results for MNP coverage and utilization showed 28.5% of all caregivers were aware of MNP, 18.5% had ever received MNP for their child, and 10.8% had fed MNP to their child in the previous 7 days. Effective coverage (ie, the child had been given the MNP at least 3 times in the previous 7 days) was 5.8%. Effective coverage of infants and young children with poor feeding practices was significantly lower as compared to those with non-poor feeding practices (coverage ratio, 0.34; confidence interval, 0.12-0.70). Most households purchased iodized salt (96.9%), fortified oil (61.0%), and fortified maize flour (93.9%). An estimated 23.9% of vitamin A requirements of children (6-23 months) were provided from fortified oil and 50.7% of iron from fortified maize flour. Most households consumed processed milk (81%). CONCLUSION: Coverage of MNPs in the surveyed neighborhoods was low. Coverage of fortified salt, oil, and maize flour was high and provided significant amount of micronutrients to children. Processed milk has potential as a vehicle for food fortification.