Logistics of using the Actiheart physical activity monitors in urban Mexico among 7- to 9-year-old children

Logistics of using new measurement devices are important to understand when developing protocols. This paper discusses the logistics of using Actiheart physical activity monitors on children in an urban, tropical environment in a developing country. Actiheart monitoring of 36 children aged 7-9 years old was undertaken for 7 days in the city of Mérida, Yucatán, Mexico. The Actiheart proved fragile for children and difficult to mend in the field. The excessive sweating due to the tropical climate caused poor adherence of the electrode pads, requiring a pad change midway through and extra pads to be provided. Also extra time was needed to be allotted for increased instructions to participants and their mothers and for individual calibration. When collecting objectively measured physical activity data under harsh conditions, the protocol must accommodate local conditions and device limitations and allow increased time with participants to obtain good quality data. © 2011 Wiley-Liss, Inc

Caesarean birth and adiposity parameters in 6- to 8-year-old urban Maya children from two cities of Yucatan, Mexico

Objectives The purpose of this study was to analyze the association between birth mode and fat mass index (FMI = fat mass [kg]/height [m]2), and z‐score values of waist circumference (WCZ) and sum of triceps and subscapular skinfolds (SumSkfZ) in a sample of 256 6‐ to 8‐year‐old urban Maya children from the cities of Merida and Motul in Yucatan, Mexico. Methods From September 2011 to January 2014, we measured height, weight, waist circumference and skinfolds in children, and height and weight in their mothers. Body composition was estimated in both generations through bioelectrical impedance analysis. Data on children's birth mode and birth weight were obtained from birth certificates. A pre‐validated questionnaire for mothers was used regarding household living conditions. Multiple regression models were used to analyze the association between birth mode and adiposity parameters, adjusting for the effect of place of residence, household crowding index, children's birth weight, and maternal fat mass. Separate regression models were run for boys and girls. Results Caesarean‐born children comprised 43% of the entire sample. Caesarean section (CS) was found to be associated with higher values of body adiposity in girls, but not in boys. Specifically, our models predicted that girls born by CS had an increased value of 0.817 kg/m2 in FMI and showed higher SDs values for WCZ and SumskfZ (0.29 and 0.32 SD, respectively) than girls who were delivered vaginally. Discussion Our results support the hypothesis that CS is associated with increased levels of adiposity in childhood, but only in girls

Caesarean birth and adiposity parameters in 6‐to 8 year‐old urban Maya children from two cities of Yucatan, Mexico [Abstract]

Caesarean birth and adiposity parameters in 6‐to 8 year‐old urban Maya children from two cities of Yucatan, Mexico [Abstract

Body mass index in mother and child dyads and its association with household size and parents’ education in 2 urban settings of Yucatan, Mexico

Background: Overweight/obesity (OW/OB) coexists in mother-child dyads. However, dearth of evidence on the factors associated with this phenomenon calls for research. Objective: To analyze the association of sociodemographic factors with OW/OB in a sample of 260 Maya mother-child dyads from Yucatan, Mexico. Methods: During 2011-2014 we measured height and weight in children and their mothers and calculated their body mass index (BMI). The OW/OB cut-off points were defined, for mothers, as having a BMI >25kg/m2 and, for children, as having a BMI-for-age >2SD of the World Health Organization references. Mother-child dyads were grouped according to their BMI status: 1) normal weight mother and child, 2) normal weight mother and OW/OB child, 3) OW/OB mother and normal weight child, and 4) OW/OB mother and child. A multinomial logistic regression model was used to analyze the interrelationships among BMI status in mother-child dyads, household size and parental education. Results: OW/OB coexisted in 40% of dyads. Compared to normal weight dyads (1), each unit increase in household size and in years of maternal education decreased the risks for the coexistence of OW/OB in motherchild dyads (OR=0.72, 95% IC 0.55-0.94, P=0.015; OR=0.70, 95% IC 0.52-0.94, P=0.019, respectively). Conversely, each year increase in paternal education increased the risk for OW/OB in dyads (OR=1.47, 95% CI 1.08-1.99, P=0.015). Conclusions: Results suggest that household size and parental education contribute to shape BMI-based nutritional status in this sample of mother-child dyads. A higher level of maternal education acts as a protective factor against OW/OB in mothers and children

Fat free mass explains the relationship between stunting and energy expenditure in urban Mexican Maya children

Background: Childhood stunting has been associated with an increased risk of obesity in adulthood, but the causes are unclear. This study hypothesizes that stunting significantly reduces both resting and activity energy expenditure. Aim: To assess and describe energy expenditure of low socio-economic Maya children and to determine whether stunting is independently related to energy expenditure after controlling for lean mass. Subjects and methods: Thirty-three urban Maya children, 17 boys, aged 7–9 years, living in Merida, Mexico, were measured for height, weight and bioelectrical impedance analysis (BIA). Body composition was estimated from BIA. Energy expenditure was measured for one week using the Actiheart (combined heart rate and accelerometer). Results: Stunting (height-for-age below the 5th percentile of NHANES III based references) affected 35% of these physically active children. Using multiple linear regression analysis, greater lean body mass predicted higher resting and activity energy expenditure. Stature was not a significant predictor of resting energy expenditure. A lower height-for-age z-score, but not stunting as a categorical variable, significantly predicted lower activity energy expenditure. Conclusion: The hypothesis that stunting reduces total energy expenditure (resting + active) in children is not supported. Rather, children with shorter stature and less lean body mass have lower total energy expenditure. Complex interactions between body size, body composition, and metabolic activity appear to elevate the risk for later life obesity in these Maya children

Globalization and children’s diets: the case of Maya of Mexico and Central America

Globalization is, in part, an economic force to bring about a closer integration of national economies. Globalization is also a biological, social and ideological process of change. Globalization results in powerful multinational corporations imposing their products on new markets. Food globalization brings about nutritional transitions, the most common being a shift from a locally-grown diet with minimally refined foods, to the modern diet of highly processed foods, high in saturated fat, animal products and sugar, and low in fiber. This paper will examine the influences of food globalization using the Maya of Mexico as a case study. The Maya people of Mexico are a poignant case. Maya health and culture has deteriorated as a result, with highly processed foods affecting physical growth and health of Maya children and their families. The case of the Maya is not isolated and we must come to terms with food globalization if we are to translate research into better child health and well-being

Effects of stunting on body composition, biological age, and muscle strength of Maya and Ladino children in Guatemala [Poster]

Effects of stunting on body composition, biological age, and muscle strength of Maya and Ladino children in Guatemala [Poster

Deep data science to prevent and treat growth faltering in Maya children

The Maya people are descended from the indigenous inhabitants of southern Mexico, Guatemala, and adjacent regions of Central America. In Guatemala, 50% of infants and children are stunted (very low height-for-age), and some rural Maya regions have >70% children stunted. A large, longitudinal, intergenerational, database was created to (1) provide deep data to prevent and treat somatic growth faltering and impaired neurocognitive development; (2) detect key dependencies and predictive relations between highly complex, time-varying, and interacting biological and cultural variables; and (3) identify targeted multifactorial intervention strategies for field testing and validation. Contributions to this database included data from the Universidad del Valle de Guatemala Longitudinal Study of Child and Adolescent Development, child growth and intergenerational studies among the Maya in Mexico, and studies about Maya migrants in the United States

The timing of adrenarche in Maya girls, Merida, Mexico

BackgroundAdrenarche involves maturation of the hypothalamic‐pituitary‐adrenal axis and increased production of dehydroepiandrosterone and its sulfate ester, dehydroepiandrosterone‐sulfate (DHEA‐S). It occurs at ages 6 to 8 in industrialized populations, marking the transition from childhood to juvenility and cognitive development at middle childhood. Studies in subsistence level populations indicate a later age (8‐9) for adrenarche, but only two such studies currently exist for comparison.AimsTo investigate adrenarcheal age among Maya girls and its association with body composition and dietary variables. We hypothesized adrenarche would occur earlier given the current dual burden of nutrition in Mexico.Materials and Methods25 Maya girls aged 7 to 9 from Merida, Mexico using ELISAs to measure salivary DHEA‐S, standard anthropometry for height, weight, and skinfolds, bioelectrical impedance for body composition variables, as well as a food frequency questionnaire for dietary information.ResultsOur hypothesis was rejected—adrenarche occurred close to 9 years. While no measures of body composition were significantly associated with adrenarcheal status, girls eating meat and dairy products more frequently had significantly higher DHEA‐S levels.DiscussionLike other populations living in ecologically challenging environments, adrenarche occurred relatively late among Maya girls. Adrenarche has been linked to measures of body composition, particularly, the adiposity or body mass index rebound, but no relevant anthropometric measures were associated, possibly because of the small sample.ConclusionFurther studies are required to illuminate how adrenarcheal variation relates to developmental plasticity, body composition, pubertal progression, and animal product consumption in other transitional populations.</div

Birth weight and body composition in 6-to-8 years old Maya children

Objective: To test the hypothesis that fetal growth, indexed by birth weight (BW), induce metabolic adjustments in the fetus that will be reflected in differences in body composition in a sample of 6-to 8-years old urban Maya children from Yucatan, Mexico.Methods: We measured height (cm), weight (kg) and triceps skinfold (mm) in 260 children (boys: 132, girls: 128), and height (cm) and weight (kg) in their mothers. Body composition was estimated in children through bioelectrical impedance analysis. Outcome variables were fat free-mass index (FFMI= fat-free mass [kg]/height [m]2) and fat mass index (FMI= fat mass [kg]/height [m]2). The main independent variable was BW z-scores. Multiple linear regression models were used to analyze the association between BW z-scores and outcome variables measured during childhood. Separate analyses were done for boys and girls. Complementary models were run using outcomes as z-scores. Models were adjusted for location, children’s and mothers’ age, mother’s body mass index and household overcrowding index. Results: BW in boys was positively associated with FFMI and FMI. FFMI increase 0.34 kg/m2 per 1-SD increase in BW and FMI increase 0.40 kg/m2 per 1-SD increase in BW. When outcomes were used as z-scores, FFMI increase 0.24 SD and FMI increase 0.18 SD per 1-SD increase in BW, respectively. Conclusion Our results are in contrast with previous findings that birth weight is more consistently associated with subsequent lean mass than with fat mass. Associations, detected only in boys, may be explained by sex differences in sensitivity to early life environments. </div