Gerardo Weisstaub

Zinc Supplementation and Growth of the Fetus and Low Birth Weight Infant

Zinc deficiency limits growth in young children, and in animal models it also affects fetal growth. In animals, the effect of severe zinc deficiency on growth is evident. However, controlled trials of zinc supplementation during pregnancy in humans have not demonstrated consistent effects on weight at birth and/or duration of gestation. Those studies that have identified a positive effect of zinc on fetal growth were performed on low-socioeconomic or migrant groups in industrialized countries or in countries where diet and living conditions are improving. In contrast, in studies conducted either on populations with minimal risk of zinc deficiency or those suffering from multiple and severe nutritional deficiencies, no effects have been found. The potential confounding factors that may help explain the contradictory results include the following: age of pregnant women; presence of digestive diseases, other nutritional deficiencies, phytates or other factors that affect bioavailability; timing and duration of zinc supplementation and compliance with supplements. Few studies of zinc supplementation were conducted on infants that were born small for their gestational age or preterm; in this case, a positive effect on growth was shown. A study of zinc supplementation during pregnancy found reduced risk of diseases (diarrhea or impetigo) in small-for-gestational-age but not preterm infants. A second study demonstrated reduced mortality in small-for-gestational-age infants. We conclude that supplementation trials during human pregnancy do not provide conclusive evidence for a beneficial effect of zinc supplementation despite the experimental evidence that zinc deficiency may retard fetal growth or shorten pregnancy. However, early zinc supplementation in low birth weight or small-for-gestational-age infants reveals an effective improvement in growth, which suggests a prenatal depletion or insufficient zinc intake to support catch-up growth postnatally.

Impact of growth patterns and early diet on obesity and cardiovascular risk factors in young children from developing countries

Non-communicable chronic diseases are now a worldwide epidemic. Diet and physical activity throughout life are among its main determinants. In countries undergoing the early stages of the nutrition transition weight gain from birth to 2 years of life is related to lean mass gain, while ponderal gain after age 2 years is related to adiposity and later diabetes and CVD risk. Evidence from developing countries undergoing the more advanced stages of the nutrition transition is limited. The early growth patterns of a cohort of Chilean children born in 2002 with normal birth weight who at 4 years had a high prevalence of obesity and CVD risk factors have been assessed. Results indicate that BMI gain in early life, particularly from 6 months to 24 months, is positively associated with adiposity and CVD risk status at 4 years. These results together with existing evidence suggest that actions to prevent obesity and nutrition-related chronic diseases in developing countries should start early in life, possibly after 6 months of age. This approach should consider assessing the effect of mode of feeding and the amount and type of energy fed, as well as the resulting growth patterns. The challenge for researchers addressing the nutrition transition is to define the optimal nutrition in early life, considering not only the short- and long-term health consequences but also taking into account the stage of the nutritional transition for the given population of interest. The latter will probably require redefining optimal postnatal growth based on the context of maternal size and fetal growth.

Melanocortin-4 receptor gene variants in Chilean families: association with childhood obesity and eating behavior

Abstract Objective: To screen for mutations in the coding region of the melanocortin-4 receptor (MC4R) gene and to assess the association between the rs17782313 variant near MC4R with childhood obesity and eating behavior. Subjects and methods: A cross-sectional sample of 221 obese Chilean children and 268 parents were incorporated in the study to assemble 134 case–parent trios. We performed direct sequencing of the MC4R coding region while the rs17782313 variant was genotyped by a Taqman assay. Eating behavior scores were calculated using the Child Eating Behavior and Three Factor Eating Questionnaires adapted for Chilean families. Results: A low frequency of genetic variation in the coding region of MC4R was found in Chilean obese children (Thr150Ile mutation and polymorphisms Ile251Leu and Val103Ile). The rs17782313 variant is possibly associated with satiety responsiveness (P = 0.01) and enjoyment of food scores (P = 0.03). Conclusion: The rs17782313 variant may influence eating behavior in obese children.

Melanocortin-3 receptor gene variants: Association with childhood obesity and eating behavior in Chilean families

OBJECTIVE To evaluate the association between melanocortin-3 receptor common genetic polymorphisms with childhood obesity and eating behavior in Chilean families. METHODS Two hundred twenty-nine obese children (6-12 y old, body mass index >95th percentile of Centers for Disease Control and Prevention/National Center for Health Statistics, 2000) and 270 parents were selected. Genotypes for MC3R genetic markers -239A>G, 17C>A (Thr6Lys), 241G>A (Val81Ile), +2138InsCAGACC, and microsatellite D20s32e were determined. Eating behavior scores were computed using the Child Eating Behavior Questionnaire and a shorter version of the Three Factor Eating Questionnaire adapted for evaluating eating inclinations in children. Genotype-obesity associations were assessed by the Transmission Disequilibrium Test. Non-parametric tests were used to compare eating behavior scores across study groups. RESULTS Allelic frequencies of -239G, 17A, 241A, and +2138InsCAGACC were estimated as 4.5%, 5.9%, 5.6%, and 17.6%, respectively, in obese children. The Transmission Disequilibrium Test in case-parent trios revealed no significant associations between childhood obesity and genetic markers, including the microsatellite D20s32e. In girls, we found significantly higher scores of the emotional eating subscale in carriers of the +2138InsCAGACC compared with non-carriers (P=0.04). In boys, carriers of 17A and 241A showed lower scores for the emotional eating subscale (P=0.01), whereas carriers of +2138InsCAGACC showed significantly lower scores for the enjoyment of food subscale compared with non-carriers (P=0.04). CONCLUSIONS There is not sufficient evidence to support the contribution for common melanocortin-3 receptor variants in childhood obesity. However, our results are concordant for a role of melanocortin-3 receptor variants in some dimensions of eating behavior such as emotional eating and enjoyment of food.

High HOMA-IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chilean youths

Burrows RA, Leiva LB, Weisstaub G, Lera LM, Albala CB, Blanco E, Gahagan S. High HOMA‐IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chilean youths.

Acute Malnutrition in Latin America: The Challenge of Ending Avoidable Deaths

In Latin America and the Caribbean, malnutrition still represents a health concern expressed mainly as stunting and micronutrient deficiencies, lessening the attention given to acute malnutrition (moderate and severe); however, the latter has a high fatality rate. Ending these avoidable deaths represents a major health and ethical challenge in the region. Acute malnutrition plus infections (mainly diarrhea and pneumonia) determine an important fraction of the fatality rate due to malnutrition in most regions, especially those with higher poverty and social instability. Application of the World Health Organization guidelines for the treatment of children with acute severe malnutrition reduces the fatality rate significantly. Among the many possibilities for treatment, systems based on day care centers and at home should be promoted. Training in the application of the World Health Organization guidelines should be incorporated into the curricula of health-related professions in countries where malnutrition is prevalent.

Non-Breast Milk Feeding in Developing Countries: Challenge from Microbial and Chemical Contaminants

Complementary foods based on cow’s milk or gruels consumed by children in developing countries are often contaminated by bacteria during preparation, and ambient temperature rapidly increases microbial load. Thus infant formula or other weaning foods may cause diarrhea in young infants accounting for 25–33% of all deaths <5 years globally. Environmental chemicals such as metals (As, Pb, Cu) and nitrates can cause vomiting/diarrea. Polychlorinated biphenyls derived from plastics, present in formula and/or breast milk, are endocrine disruptors (the potential threats are not fully quantifiable). The prevailing view is that benefits from breastfeeding outweigh potential risks.

Prevalence of metabolic syndrome in obese Chilean children and association with gene variants of the leptin-melanocortin system.

Abstract Metabolic syndrome (MS) related to adult type 2 diabetes mellitus and cardiovascular disease is prevalent among obese children/adolescents. Genetic variants of the leptin-melanocortin system have been associated with components of MS. The aim of our study is to estimate the prevalence of MS (according to Cook’s criteria) in a Chilean cross-sectional sample of 259 obese children (47.1% girls, aged 6–12 years), and to assess the association between common genetic variants of leptin-melanocortin pathway genes (LEP, LEPR, POMC, MC3R and MC4R) with components of the MS using logistic regression. We observed an overall MS prevalence of 26.3% (32.2% in girls and 21.1% in boys) in obese Chilean children. No associations were detected between genetic variants of leptin-melanocortin genes and MS components. MS prevalence among our obese children sample is similar to those previously described in Chile, demonstrating the increased risk of diseases in adulthood that obese children carry.

GOCS cohort: children's eating behavior scores and BMI.

Background/Objective:In Chile, approximately one in three children under 6 years of age reported overweight/obese, while one in four children in elementary school suffer from obesity. There is a paucity of population-based information on the influence of childhood eating behavior on anthropometric measures related to obesity. To assess the association between eating behavior scores and Body Mass Index (BMI) z-scores in 7–10-year-old Chilean children.Subjects/Methods:We conducted a cross-sectional study in 1058 children aged 7–10 (51% girls) from the ‘Growth and Obesity Chilean Cohort Study’ (GOCS). Direct measures of weight and height were used to compute BMI z-scores according to World Health Organization (WHO) curves. Children were classified as normal weight (−1<1 s.d.), overweight (1<2 s.d.) and obese (⩾2 s.d.). Eating behavior scores were measured through the Child Eating Behavior Questionnaire (CEBQ), previously adapted and validated for Chilean children. Multiple linear regressions were carried out using BMI z-score as the outcome and eating behavior scores as explanatory variables. All models were adjusted by age and gender.Results:BMI z-scores were positively associated with pro-intake scores in the subscales ‘enjoyment of food’, ‘emotional overeating’ and ‘food responsiveness’ (P<0.0001). Contrary to other studies, ‘desire for drinks’ scores were also associated with BMI z-scores (P<0.0001). In contrast, food-avoidant ‘satiety responsiveness’, ‘slowness in eating’ and ‘food-fussiness’ scores were negatively associated with BMI z-scores (P<0.0001).Conclusion:We found a significant relationship between eating behavior scores and BMI z-scores in Chilean children, showing that BMI in 7–10-year-old Chilean children is positively associated with pro-intake eating behavior scores and negatively associated with anti-intake eating behavior scores. The identification of specific eating behaviors patterns related to obesity will provide important information for the implementation of prevention programs for this disease.

Treatment and prevention of malnutrition in Latin America: focus on Chile and Bolivia.

Seven million children under 5 years of age died worldwide in 2011, and one-third had malnutrition. Latin America and Caribbean countries stand out for the notable improvement of their health and nutrition situation, particularly in pregnant women and young children. Nutrition-sensitive interventions such as promoting food security, womens empowerment, social safety nets, clean water, and sanitation, among others, are critical for success. In Bolivia, the program Desnutrición Cero (Malnutrition Zero) was able to reduce mortality from severe malnutrition after 5 years from 25% to less than 5%, based on widespread implementation of the World Health Organization 10-steps protocol for hospitalized care and the application of community management. The Economic Commission for Latin America estimated the cost of malnutrition for Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama, and the Dominican Republic as US