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Background: Socioeconomic factors influence diet quality during pregnancy. However, a dearth of evidence about the influence on energy and macronutrients adequacy calls for research. Objective: To analyze the association between socioeconomic factors and adequacy rates of energy and macronutrient intakes in pregnant women from Merida, Yucatan, Mexico. Methods: During September to December 2019, we applied a socioeconomic questionnaire and three 24-hour dietary recalls to 83 pregnant females resident in Merida, Yucatan. Energy and macronutrient intakes were compared with the estimated trimester-specific energy and macronutrient requirements to calculate adequacies (%). Outcome variables were average adequacy of energy, carbohydrates, total fat, and protein intakes and the main predictors were maternal education, monthly family income, working status, and marital status. Descriptive statistics of adequacy were calculated for each category of predictors. The association between socioeconomic factors and outcome variables was analyzed through simple and multiple linear regression models. Results: Adequacy rates of energy and macronutrients decreased as education and familial income levels increased, as well as among unemployed women. Consistently with these results, simple linear regressions showed that years of education, family income, and working status (i.e., women working to earn money), were negatively associated with adequacy rates of energy and macronutrients intakes. When all predictors and covariates were included in a multiple linear regression model, only having a job was significantly associated with adequacy rates. Marital status was not associated with outcomes. Conclusions: Women in disadvantaged socioeconomic conditions (unemployed and low levels of education and familial income) show greater energy and macronutrient intakes.

In this observational study, our aim was to analyse the association between pre-pregnancy BMI and adequacy rates of energy and macronutrient intakes in a sample of pregnant women from Yucatan, Mexico. From September to December 2019, we collected data on socioeconomic, pregnancy, and dietary characteristics, and took anthropometric measurements of women during household visits. Pre-pregnancy BMI was calculated from measured height and self-reported body weight. Energy and macronutrient intakes (obtained from three 24-h dietary recalls) were compared with the estimated trimester-specific requirements to calculate adequacies (%). Multiple linear regression models showed that after accounting for maternal socioeconomic characteristics and perinatal variables, each unit increase in pre-pregnancy BMI was associated with decreases of 2%, 2%, and 2.6% in energy, carbohydrate, and total fat intakes, respectively. These results were significant when under- and over-reporters were excluded from the analyses. Women who enter pregnancy with higher BMI values may voluntarily or involuntarily reduce their food intake.IMPACT STATEMENT

This study analyzes the influence of grandmothers’ household residency on the presence of low height-for-age and excessive fat (FMI = fat mass [kg]/height [m2]), waist circumference, and sum of triceps and subscapular skinfolds in a sample of 247 6- to 8-year-old urban Maya children from Yucatan, Mexico. Between September 2011 and January 2014, we obtained anthropometric and body composition data from children and mothers, as well as socioeconomic characteristics of participants and households. Grandmothers’ place of residence was categorized as either in the same household as their grandchildren (n = 71) or in separate households (n = 176). Multiple logistic regression models were used to analyze the association between grandmothers’ residency and outcome variables. Models were adjusted for maternal anthropometric characteristics and the following socioeconomic variables: family size, location, maternal education, monthly family income, and household crowding. Models showed that the presence of grandmothers in their grandchildren’s households was not associated with any of the outcome variables. In contrast, larger family size, overcrowding in the household, and lower family income predicted low height-for-age in children. Larger family size decreased the risk for being overweight based on the three parameters of body composition. Overcrowding in the household increased the risk for greater skinfolds thickness, while low family income increased the risk for higher fat mass index. The residency of grandmothers in their adult daughters’ households is not significantly associated with the outcome variables in this sample of urban Maya families. Instead, maternal anthropometric characteristics and socioeconomic conditions of the family have a greater influence on the overall growth of children.

In 2020, while living through unprecedented health outcomes from the COVID-19 epidemic in Mexico, a human ecology perspective provides us with an unconventional way to analyze the role of the media...

To develop sex- and gestational age specific reference percentiles and curves for birth weight and length for Yucatec neonates using data from birth registers of infants born during 2015-2019.Observational, descriptive, epidemiologic study in a 5-year period including every registered birth in the state of Yucatan, Mexico using birth registries. A total of 158 432 live, physically healthy singletons (76 442 females and 81 990 males) between 25 and 42 weeks of gestation were included in the analysis. We used the LMS method to construct smoothed reference centiles (3rd, 10th, 25th, 50th, 75th, 95th, and 97th) and curves for males and females separately.Mean maternal age was 26 (SD = 6.22) years. Fifty-two percent of births occurred by vaginal delivery, 37% were firstborn and similar proportions were second (33%) and third or more (30%) born. 5.5% of newborns included in the references corresponds to neonates born before 37 weeks of gestation (5.9% boys and 5.1% girls). In both sexes, the percentage of infants with a birthweight less than 2500 g was 6.7%. The birthweight at the 50th percentile for males and females at 40 weeks of gestation in this cohort was 3256 and 3167 g, respectively, and the corresponding values for birth length were 50.23 and 49.84 cm (mean differences between sexes: 89 g and 0.40 cm, respectively).The reference percentile and curves developed in this study are useful for research purposes and can help health practitioners to assess the biological status of infants born in Yucatán.

Background:Overweight/obesity (OW/OB) coexists in mother–child dyads. However, a 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 to 2014, we measured height and weight in children and their mothers and calculated their body mass index (BMI). The OW/OB cutoff points were defined, for mothers, as having a BMI >25 kg/m2and, for children, as having a BMI-for-age >2 standard deviation 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:Overweight/obesity 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 of the coexistence of OW/OB in mother–child dyads (odds ratio [OR] = 0.72, 95% confidence interval [CI] 0.55-0.94, P = .015; OR = 0.70, 95% CI 0.52-0.94, P = .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 = .015).Conclusions:Results suggest that household size and parental education contribute to shape BMI-based nutritional status in this sample of mother–child dyads.

In humans, high levels of investment are required to raise offspring, because of the prolonged developmental period and short interbirth intervals. The costs borne by individual mothers may be mitigated by obtaining social support from others. This strategy could be particularly valuable for first-time mothers, who lack first-hand experience and whose offspring have higher mortality risk than later-born siblings. As raising children is potentially stressful, mothers may gain from others sharing their experience, providing knowledge/information and emotional support. Being genetically related to both mother and grandchild, maternal grandmothers may be especially well placed to provide such support, while also gaining fitness benefits. We tested the over-arching hypothesis that first-time mothers and their young children supported by the maternal grandmother would have lower levels of stress and better health outcomes, compared to mother–infant dyads lacking such grandmaternal support. A cohort of 90 mother–infant dyads (52 with grandmaternal support, 38 without) was recruited in Merida, Mexico. We assessed anthropometry and body composition in both mother and child, along with maternally perceived stress and child temperament, and documented maternal social relationships. No differences were found in perceived stress/temperament or anthropometry of either mothers or children, according to the presence/absence of grandmaternal support. However, a composite score of whether grandmothers provided advice on infant feeding was positively associated with child nutritional status. Mothers without grandmaternal support reported seeking more informational and emotional support from other female relatives for childcare, potentially compensating for limited/absent grandmaternal support. Our findings may help develop interventions to improve maternal and child health by targeting the dynamics of maternal social networks. This article is part of the theme issue ‘Multidisciplinary perspectives on social support and maternal–child health’.

Background Adrenarche 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. Aims To 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 Methods 25 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. Results Our 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. Discussion Like 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. Conclusion Further studies are required to illuminate how adrenarcheal variation relates to developmental plasticity, body composition, pubertal progression, and animal product consumption in other transitional populations.

© 2020 Wiley Periodicals, Inc. Objectives: To analyze the relationship of birth weight, birth order, breastfeeding duration, and age of introduction of solid foods with height, fat mass, and fat-free mass in a sample of Maya children when aged 6 to 8 years old. Methods: We collected data on anthropometry, body composition, children's birth weight, birth order, early feeding practices, and household socioeconomic characteristics in a sample of 260 Maya children aged 6 to 8 years living in Merida and Motul, two cities in Yucatan, Mexico. Multiple regression models were performed to identify variables associated with height-for-age (HAZ), fat mass index (FMI), and fat-free mass index (FFMI). The predictors included in the models were birth weight (kg), birth order, duration of breastfeeding (months), age at introduction of solid foods (months), maternal age (years), and height (cm). Models were adjusted for the influence of children's age and sex, maternal educational level, and household overcrowding. Results: HAZ was positively associated with child birthweight and maternal height and age, but inversely associated with birth order and age of introduction of solid foods. FMI was positively associated with birth weight, maternal age, and height, and negatively associated with birth order. FFMI was positively associated with maternal age and birth weight. Conclusions: These results are evidence of the importance of the first 1000 days of life for the growth and body composition of Maya children and contributed to understand the development of nutritional dual burden in this population.

Height cannot always be measured directly, hence the need for height estimation formulae. This study presents two new linear regression equations for estimating height from tibial length among Maya populations. Body height and percutaneous tibial length were measured in two living Maya samples from the state of Yucatan, Mexico. The first sample comprises 100 adults (63 females and 37 males) from the community of Dzemul, (Group 1) and the second sample comprises 71 adults (26 females and 45 males) from the city of Mérida (Group 2). A linear regression model equation was then adjusted to estimate height from tibia length for each group. These models were then compared using 95% confidence intervals for the estimated variables. No differences were observed between the equations at this interval. Thus, both equations appear adequate for estimating body height from tibia length in contemporary Yucatecan populations. While the formula of Group 1 is applicable also to bioarcheological studies, the formula of Group 2 is more appropriate for studies in living populations.

Comunicamos resultados centrales de un proyecto multidisciplinario que abordó la corporeidad humana como un producto social, histórico, inmerso en un campo de ejercicio del poder. Nuestros estudios de grupos mayas en Mérida, Yucatán, realizados en los últimos quince años, evidencian las consecuencias a largo plazo de las condiciones de vida en que nacen, crecen y se reproducen. El panorama es desalentador, pues el crecimiento y estado nutricional de niños y madres adultas participantes expresan los efectos de carencias y pobreza crónicas que han sido una constante entre la población maya de Yucatán. Entre ellos coexiste la mala nutrición en dos facetas: desnutrición crónica -expresada por el desmedro, en los niños, y talla baja en las mujeres adultas- y sobrepeso muy frecuente entre mujeres adultas. Finalmente, encontramos indicios de que las pobres condiciones de vida experimentadas por madres y abuelas mayas tienen efectos adversos en las generaciones más recientes.

Globalization is an economic force to bring about a closer integration of national economies. Globalization also has effects on human biology. 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. Food globalization also changes the social, economic, and political ecology and increases poverty for some. This chapter examines the influences of food globalization using the Maya children of Yucatan as a case study. Yucatecan Maya children often live in poverty and suffer the dual-burden of stunting (low height-for-age) and overweight/obesity. This may be due to eating processed foods with insufficient essential nutrients for normal metabolism and growth, to an energy imbalance related to sedentary behavior, to social and emotional stress of poverty that inhibit height growth, or some combination of these. The case of the Yucatan 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.

We critically analyze definitions of growth stunting and low height-for-age, focusing on the arbitrary cut-off points that classify people dichotomously as “stunted” or “non-stunted.” We discuss how individuals may be included or excluded in one of such categories, depending on the standard or references used, and list inherent health implications. We analyze data on prevalence and predictors of stunting among Maya children and adults in Yucatan, to highlight pros and cons of using dichotomized versus continuous height-for-age data. Stunting among Yucatecan Maya children has decreased since the 1990s (Azcorra et al., Growth status in children and adolescents in Yucatan, Mexico: a human ecology perspective. In: Studies in human ecology, House for Science and Technology, Ha Noi, p. 120–138, 2010) but prevalence of low height-for-age continues to be high, throughout the growing period (Mendez Dominguez, Aspectos del ambiente familiar y escolar relativos a los habitos de alimentacion y actividad fisica que se asocian al exceso de peso entre escolares de Merida, Yucatan, 2013; Azcorra-Perez, Intergenerational factors that shape the nutritional status of urban Maya households in Merida, Mexico. A 3-generations study, 2014). Male and female adult Maya average stature has not changed in 100 years and remains extremely low (Steggerda, Maya Indians of Yucatan. Carnegie Institution of Washington, Washington, DC, 1941; McCullough, Am J Phys Anthropol 58:221–225, 1982; Dickinson et al., Estud Antropol Biol. 4:123–150, 1989; Varela-Silva et al., Coll Anthropol 36:39–45, 2012). Short stature has been associated with increased risk for cardiovascular diseases and other noncommunicable diseases and its effects seem to be potentiated by overweight/obesity (OW/OB). This is especially true among the Maya who also show an elevated accumulation of centralized fat. The association of being short in stature with being OW/OB produces negative health outcomes that are stronger and more pernicious than the ones seen in populations where only one of the conditions happens, in the absence of the other. We highlight some aspects that may help to answer the following questions: i) why is the prevalence of stunting decreasing among Maya children but the prevalence of low height-for-age during growing years remains high, and ii) why has the stature of the adult Maya remained unchangeable in the last century?

Today a considerable proportion of Yucatecan Maya reside in urban areas, with the city of Merida being a site with a long history of settlement. The Maya bring with them a historical legacy of poverty and abusive treatment during the more than 500 years of European and then Mestizo domination. This chapter discusses, from a human ecology perspective, the biological consequences of chronic adverse living conditions experienced by the Maya in the context of a research project in which we studied a sample of grandmothers, mothers, and grandchildren from the city of Merida. Our results highlight three important biological phenomena: (1) the coexistence of undernutrition and overweight, both extremes of malnutrition, at the individual and mother-child dyads levels, (2) the growth and nutrition status of recent generations are shaped by conditions experienced by recent maternal ancestors, and, (3) overall, the phenotype of Maya people studied is the result of historical trauma experienced during the colonial period and decades after Mexican independence.

Immigration is a process that allows an individual to acquire capitals linked to attributes of education: knowledge, abilities, attitudes and values. Intrastate migration is a major phenomenon in Mexico that is dominated by women. In 2010, Yucatan was the state with the most internal movement. We applied a four-stage model to analyze migration among nine immigrant Maya women in Merida, the capital of Yucatan, during 2011. Semi-structured interviews were used to collect data. Using this theoretical basis and content analysis, we identified types of capitals and their relationship to attributes of education, and how the studied women had used them during their rural-to-urban migration. Emphasis was placed on the Instability and Establishment stages, and the adjustments they made in their new urban environment. Immigration is clearly an element of informal education that allowed the studied women to develop new decision-making skills and ways of appreciating themselves.

Objective: To analyze the association between relative leg length – RLL – (leg length x 100/height) and adiposity in a sample of 6 to 8-year-old children of Maya ancestry from Motul and Merida, Mexico. Methods: This cross-sectional study included 260 children (128 girls) measured between 2011 and 2015. The RLL was used as a measure of body proportionality. Linear regression models were performed to examine the association between RLL (predictor) and three adiposity indicators (outcome variables): fat mass index (kg/m2), waist circumference (z-score) and sum of triceps and subscapular skinfolds (z-score). Results: The prevalence of stunting was 12%, and a higher prevalence (19%) of short RLL (leg stunting) was found. The prevalence of overweight and obesity were 16 and 20%, respectively, but the highest was found for abdominal obesity (40%). None of the adiposity indicators were related to RLL (p>0.05), even after adjusting for the influence of children’s sex and age. Conclusions: Our results suggest that the coexistence of short RLL and high body adiposity is not observed in all populations. Our findings do not discount the possibility that a negative association between RLL and adiposity is expressed at older ages.

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.

Objectives To analyze differences in knee height (KH) between adult Maya mothers and daughters in the city of Merida, Mexico, and determine if these differences are associated to their childhood socioeconomic conditions. Methods From September 2011 to January 2014, we measured KH and collected data on childhood conditions (place of birth, type of drinking water, family size [FS] and fathers’ occupation) from a sample of 180 Maya mother-daughter dyads. Mean intergenerational difference in KH was calculated and compared for each category of socioeconomic variables and a multiple regression model was adjusted to assess the association between childhood conditions and difference in KH. Results A relative increase of 1.05 cm (SD = 2.3 cm) or 0.45 standard deviations (effect size of difference) was observed in KH between generations. Place of birth and FS were significantly associated to KH. The intergenerational KH difference was 1.6 cm longer when mothers were born outside Merida but daughters were born in the city. Daughters with larger FS than their mothers associated to a decrease in KH difference (1.6 cm) compared to daughters and mothers having the same FS. Conclusions The relative represents a portion of the expected change in growth in a group that has experienced few substantial improvements in their living conditions. Slight improvements in childhood living conditions resulting from the intergenerational transition from rural to urban environments seem to be linked to a slight intergenerational increase in KH among Maya women in Merida.

Objectives To test the hypothesis that living conditions experienced by maternal grandmothers (F1 generation) and mothers (F2 generation) during their childhood are related to height and leg length (LL: height − sitting height) of their 6-to-8 year old children (F3 generation). Methods From September 2011 to June 2012 we obtained height and LL, and calculated z-score values of these measurements for 109 triads (F1, F2, F3) who are Maya living in Merida, Yucatan, Mexico. Multiple regression models were adjusted to examine the relation of anthropometric and intergenerational socioeconomic parameters of F1 (house index and family size during childhood) and F2 (paternal job loss during childhood) with the z-score values of height and LL of F3. Results Children's height and LL were positively associated with maternal height and LL. This association was relatively stronger in LL. Better categories of grand-maternal house index were significantly associated with higher values of height and LL in grandchildren. Grand-maternal family size was positively related with LL, but not with height. Conclusions Our findings partially support the hypothesis that living conditions experienced by recent maternal ancestors (F1 and F2) during their growth period influence the growth of descendants (F3). Results suggest that LL is more sensitive to intergenerational influences than is total height and that the transition from a traditional rural lifestyle to urban conditions results in new exposures for risk in human physical growth. Am. J. Hum. Biol. 27:494–500, 2015. © 2015 Wiley Periodicals, Inc.

OBJECTIVES: To analyze whether living conditions, experienced by mothers and adult daughters during their childhood, are associated with age at menarche (AAM) in daughters. METHODS: From September, 2011, to January, 2014, AAM and childhood living conditions were collected from a sample of 246 dyads of Maya mothers (mean age = 59.60 years, SD = 8.64) and their adult daughters (mean age = 33.03 years, SD = 5.57) from the cities of Merida and Motul in Yucatan, Mexico. Indicators of childhood living conditions were number of siblings and quality of house construction materials in both generations, and father's absence among daughters in their pre-menarcheal years. Multiple regression models were used to assess the association between childhood conditions in mother-daughter dyads and daughter's AAM. RESULTS: The recalled mean AAM of adult Maya daughters was 12.05 years (SD = 1.53). After adjusting for the influence of mothers' AAM, number of siblings in both the mothers' and daughters' families directly predicted daughters' AAM (more siblings was associated with a later AAM); and a higher (better) index of household conditions in mothers' childhood was associated with earlier AAM in daughters. The household conditions index during the childhood of daughters and father's absence were not associated with their AAM. CONCLUSIONS: Our results suggest that better living conditions experienced by the mothers and daughters during their childhood may lower mean AAM in daughters in the context of populations that show important intergenerational changes in their social and economic conditions.

This qualitative study reports the findings from 6 focus groups conducted at a clinic in Southern Mexico with caregivers of morbidly obese children. This study was developed with the purpose of gaining a further understanding of caregivers' perceived role in addressing their children's obesity within the family context and identifying topics that could be considered when providing health care in similar sociocultural environments. We identified that although caregivers acknowledge the role of modifiable factors in obesity prevention and treatment, they held beliefs about determinism in obesity. In addition, diet was the more frequently identified means of reducing the impact of obesity. The importance of role modeling and promoting healthy behaviors in the family context are topics that could be addressed in clinical practice.

Intake pattern of macronutrients (protein, lipid, carbohydrate) and socioeconomic status (SES) are major causes of high child and adolescent overweight and obesity prevalences in Mexico. An evaluation was done of the relationship between body mass index (BMI)-based nutritional status and body composition (BC), macronutrient intake rates (MIR) and SES indicators in 127 boys and 156 girls aged 12 to 16 years attending schools in Merida, Mexico. Anthropometric variables included height, weight, and BMI. The BC (body fat mass, fat-free mass, dry lean mass) was estimated by bioelectrical impedance (Bodystat 1500 MDD). The MIR were estimated following FAO/WHO/UNO standard (1985). Proxy socioeconomic indicators included parents' age (as a maturity indicator) and education, fathers' occupation, school type and monthly household food expenditure per capita. Excess weight (overweight + obesity) assessed by BMI, was higher in boys (40.16 %) than in girls (33.97 %). Boys had higher BMI, less fat mass and higher fat-free mass than girls. The MIR did not vary significantly in response to age, sex, BC or SES. Participants with higher SES were taller and heavier, had higher fat-free mass and lower fat mass. In the studied adolescents, anthropometric and BC values, and overweight and obesity rates were more associated with SES than MIR.

The co-existence of very short stature due to poor chronic environment in early life and obesity is becoming a public health concern in rapidly transitioning populations with high levels of poverty. Individuals who have very short stature seem to be at an increased risk of obesity in times of relative caloric abundance. Increasing evidence shows that an individual is influenced by exposures in previous generations. This study assesses whether maternal poor early life environment predicts her child's adiposity using cross sectional design on Maya schoolchildren aged 7-9 and their mothers (n = 57 pairs). We compared maternal chronic early life environment (stature) with her child's adiposity (body mass index [BMI] z-score, waist circumference z-score, and percentage body fat) using multiple linear regression, controlling for the child's own environmental exposures (household sanitation and maternal parity). The research was performed in the south of Merida, Yucatan, Mexico, a low socioeconomic urban area in an upper middle income country. The Maya mothers were very short, with a mean stature of 147 cm. The children had fairly high adiposity levels, with BMI and waist circumference z-scores above the reference median. Maternal stature did not significantly predict any child adiposity indicator. There does not appear to be an intergenerational component of maternal early life chronic under-nutrition on her child's obesity risk within this free living population living in poverty. These results suggest that the co-existence of very short stature and obesity appears to be primarily due to exposures and experiences within a generation rather than across generations.

Objective Identify the biological, social, and economic conditions influencing the knee height/stature index (KHSI) in growing individuals of Maya ancestry in the city of Merida, Yucatan, Mexico. Methods The hypothesis was that KHSI values would be lower in subjects with two Maya surnames. This was tested by analyzing the effect of a series of environmental, biological, and socioeconomic variables on stature and knee height (KH). Data were collected from 2008 to 2009 from 841 individuals (444 girls), 9 to 17 years of age, in Merida, Yucatan, Mexico. Ancestry was used as a proxy for genetics, and based on number of Maya surnames (2, 1, or none). The KHSI was calculated for all individuals. Multiple regression models were run to identify the variables that best explained variation in stature, KH, and KHSI. Results Ancestry negatively (P

Objectives To test the hypothesis that leg length-relative-to-stature is a more sensitive indicator of nutrition and health than is total height (HT) or sitting height (SH) in a sample of 109 triads of urban Maya children (6.0–8.99 years), their mothers, and maternal grandmothers from Merida, Mexico. Methods From September 2011 to June 2012, the following factors were obtained from all participants: (1) HT, SH, and leg length (LL); (2) the sitting height ratio (SHR = [SH × 100]/HT), relative leg length index (RLLI = [LL × 100]/height), and percentiles and z-scores of HT, SH, and LL were calculated; and (3) the percentages of stunting for children or very short ZHT for the adults, short ZSH, and short ZLL: HT-for-age, SH-for-age, or LL-for-age below the 5th percentile of the reference were calculated. Correlations were performed to examine the association between z-scores of HT, SH, and LL among three generations. Results Stunting in children was 11% (short ZLL = 29%, short ZSH = 7%). Short ZHT was present in 71% of mothers (short ZLL = 54%, short ZSH = 50%) and 90% of grandmothers (short ZLL = 69%, short ZSH = 83%). Significant correlations in ZHT, ZSH, and ZLL were found in mother-to-child and grandmother-to-mother, with the strongest correlations for ZLL. Conclusions These findings support the hypothesis for children and mothers. Based on ZLL, there is evidence that childhood and nutrition have improved somewhat for each younger generation. Persistent environmental adversity during growth resulted in growth deficits for LL and SH for the mothers and grandmothers. Am. J. Hum. Biol., 25:659–665, 2013. © 2013 Wiley Periodicals, Inc.

Background: Obesity has negative impact on health and socialization. Previous studies found that children with obesity have lower grades, but it is unclear: a) if specific subject might affect their grade point averages, b) if the results of standardized tests and school grades are the same for children with and without obesity in a community where pediatric obesity is highly prevalent. Objectives: The current study aimed to compare school grades and standardized test scores of children with and without obesity in a probabilistic sample of primary school children from Southern Mexico, where overweight/obesity is highly prevalent. Methods: The study measured a probabilistic sample of 2971 children going to public primary schools in Merida, Mexico, transformed the anthropometric data into body mass index (BMI) z-scores according the world health organization (WHO) reference values and categorized children according to their BMI status, and the scores they obtained in national standardized tests (n = 2791). The study analyzed the association between children with/without obesity and their academic performance in terms of school grades and standardized tests using mean comparison T-tests and multinomial logistic regression models using Stata 12. Results: Differences were observed between obese and non-obese children in overall grade point averages; however, no differences were observed on national standardized academic test scores. In analyzing specific academic subject areas, no differences were observed in grades for math, literature, social sciences, life sciences and art. The only significant difference observed was in the grade for physical education with obese students earning lower grades than their non-obese counterparts. Conclusions: There were no significant differences between the children with obesity and those without obesity in standardized tests. Students without obesity had significantly higher grade point average than their peers with obesity (8.4 and 8.5, respectively; P < 0.000).

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.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.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).Stunting (height-for-age below the 5(th) 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.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.

To understand age-sex variation of stature and upper arm length (UAL) and to estimate stature from UAL through prediction equations.A cross-sectional study was undertaken in 2006-2007 among 458 children (218 boys and 240 girls) aged 4.0 to 6.92 y of south Merida in Yucatan, Mexico.The results show significant age variation (p 0.001) of stature and upper arm length (UAL) in children. Boys show significantly higher mean stature and UAL compared to the girls. Relative proportion of upper arm length to stature is greater in boys. Interrelationship between stature and upper arm length exhibits significant association with respect to age and sex of children. Reconstruction of stature from upper arm length through regression analysis also gives good prediction models for separate and combined samples of both sexes with age. Regression coefficients for UAL predicting stature account for 0.90 or greater variance in the dependent variable (stature). The difference between reconstructed stature and the actual measurement is less than ±2.00 cm.UAL appears to be a reliable indicator to estimate stature in children aged 4.0 to 6.92 y old.

The problem whether the pubertal spurt is a single developmental effort or series of changes with dominance of intensified increments was considered. The examinations took place in the tropical climate of Yucatan and included 49 boys and 47 girls aged 11-13 years and being of the Maya, Mestizo and Creole origin. The youths were attending two schools located in rather poor districts of Merida city (Yucatan, Mexico). The measurements started in February 2002 and were continued monthly till November 2003. The standard anthropometric methodology was applied to measure body height, weight, arm, waist, hip and calf circumferences and five subcutaneous fat folds. Bioimpedance techniques were used to measure fat mass (FM), fat free mass (FFM) and total body water (TBW). Age at menarche was detected. The results show that each individual and its variable show a different rate of changes. It suggests that the rate of development and changes of body mass and fat mass are occasional. The only regularity shows that rather short (1-3 months) periods of rapid growth (saltations) are divided by slower growth periods (stasis), but their duration and time of occurrence have a very individual character. The rate and rhythm of each body build variables are also different. These phenomena depend rather on conditions in which the development of each individual occurs, probably as well as on its genetic predispositions and ecosensitivity. The differences in onset and intensity of pubertal spurt depend on alternations between periods of saltations and stasis of growth processes and on changes in body mass. The specific monthly rate of changes of body build measures, typical for studied group of youths and/or seasonal changes according to climatic conditions (cyclic changes in nature) were not observed. The preliminary results suggested that observed changes rather depend on an adjustment to local living conditions, mostly on nutrition and mode of life (physical activity and leisure). These studies need to be repeated during a longer period of time (at least within 5-year period), in different climatic conditions and social groups.

The results of an analysis of the viewpoints of Celestun community members regarding the Ria Celestun Biosphere Reserve, Mexico, are used as the basis for recommendation to improve the community/natural protected area (NPA) relationship. Participant observation was used to record the opinions of 80 people (8–83 years of age) between April and August 2002. Twenty semistructured interviews were held with local young people randomly selected from the participant observation group and their fathers; one interview was held with a municipal officer. Results indicate that the informants perceived a lack of communication between community members and the Reserve concerning its objectives and action areas, minimal community participation in Reserve regulation development, an absence of alternative productive activities and unjustified restriction of natural resources. These perceived conditions can potentially generate conflict between the community and the Reserve administration, preventing fulfillment of the Reserve’s environmental protection mission and negatively affecting community welfare. It is suggested that communication between the Reserve and the community be mutual and free-flowing, that Reserve objectives be identified in conjunction with the community, that community members be included in Reserve activities and administration, that interdisciplinary teams be formed to encourage communication and participation and that alternative productive activities be developed. Particular emphasis is placed on the need to listen to and address the concerns of young people because they will define the community/Reserve relationship in the near future.

Objective To analyze the relationship between maternal height, offspring birth weight, and adiposity at 6–10 years of age in a sample of 197 mother–child dyads from Merida, Mexico. Materials and methods During 2008–2009 and 2011–2013, measurements were taken of maternal height and weight; and height, waist circumference (WC), and skinfolds (triceps, subscapular, and suprailiac) of their children. Participant body composition was estimated using a bioelectrical impedance analyzer. A questionnaire was applied to document household socioeconomic conditions. Multiple linear regression models were used to study the association between maternal height, offspring birth weight and fat mass index (FMI), WC, and sum of skinfolds (SumSkfZ) in boys and girls, separately. Results After adjusting for child age and household socioeconomic conditions, maternal height was identified to be significantly associated (p

SummaryObesity affects quality of life and increases the risk of morbidity and mortality. Mexico, a middle-income country, has a high prevalence of overweight and obesity among urban children. Merida is the most populated and growing city in southern Mexico with a mixed Mayan and non-Maya population. Local urbanization and access to industrialized foods have impacted the eating habits and physical activity of children, increasing the risk of overweight and obesity. This study aimed to contribute to the existing literature on the global prevalence of overweight and obesity and examined the association of parental income, ethnicity and nutritional status with body mass index (BMI) and height in primary school children in Merida. The heights and weights of 3243 children aged 6–12 from sixteen randomly selected schools in the city were collected between April and December 2012. Multinomial logistic regression models were used to examine differences in the prevalence of BMI and height categories (based on WHO reference values) by ethnicity and income levels. Of the total students, 1648 (50.9%) were overweight or obese. Stunting was found in 227 children (7%), while 755 (23.3%) were defined as having short stature. Combined stunting and overweight/obesity was found in 301 students (9.3%) and twelve (0.4%) were classified as stunted and of low weight. Having two Mayan surnames was inversely associated with having adequate height (OR=0.69, p