Obesity-promoting factors in Mexican children and adolescents: challenges and opportunities

Es Niño o Niña?: Gender Differences in Feeding Practices and Obesity Risk among Latino Infants

Background

Obesity prevalence is significantly higher among Latino boys than girls. Weight status at 12 mo, a significant predictor of childhood obesity, is associated with feeding practices during infancy.

Objectives

The objectives were to examine breastfeeding and formula-feeding practices overall and by infant gender and to examine relations among infant gender, milk-feeding practices, and obesity risk among Latino infants over the first year of life.

Methods

Latino mother-infant dyads (n = 90) were recruited from a pediatric clinic. Mothers were interviewed at regular intervals (infants aged 2, 4, 6, and 9 mo), and 24-h feeding recalls were conducted when infants were aged 6 and 9 mo. Infants' lengths and weights were retrieved from clinic records to calculate weight-for-length percentiles. A bivariate analysis was conducted to compare feeding practices by gender and mediation analysis to test whether feeding practices mediated the relation between gender and obesity risk.

Results

The majority (80%) of mothers were born outside the United States. In early infancy, mixed feeding of formula and breastfeeding was common. At 6 and 9 mo of age, milk-feeding practices differed, with formula feeding more common for boys than girls. At 12 mo, 38% of infants experienced obesity risk (≥85th weight-for-length percentile). Infants' obesity risk increased by 18% per 1 oz increase in powdered formula intake. Formula intake among boys was on average 1.42 oz (in dry weight) higher than that among girls, which, in turn, mediated their increased obesity risk (IERR = 1.27, 95% confidence interval: 1.02, 1.90).

Conclusions

The increased obesity risk among Latino boys compared with girls at 12 mo was explained by higher rates of formula feeding at 6 and 9 mo of age. Future investigations of cultural values and beliefs in gender-related feeding practices are warranted to understand the differences in obesity risk between Latino boys and girls.

Clustering Health Behaviors in Mexican Adolescents: The HELENA-MEX Study

Purpose: The prevalence of excess weight within the adolescent population is rapidly increasing in Mexico, especially in areas with lower socioeconomic status. The present study aimed to identify lifestyle clustered patterns in adolescents and analyze the associations among these clusters and body composition. Method: A final sample of n=259 participants (13 to 17 years old, 58.7% girls), residents in rural and urban areas, were included. Hierarchical and k-means clusters analyses included moderate to vigorous physical activity (MVPA), cardiorespiratory fitness (CRF), handgrip strength, screen time, sleep time, and diet. The associations between cluster membership and body composition were analyzed through general linear models (ANCOVA), including sex, age, place of residence, and socioeconomic status as covariates. Results: Three different clusters were identified: Cluster 1, [Unhealthy] (low values in all lifestyle patterns), Cluster 2, [Low Physical Fitness] (low values in CRF and handgrip strength) and Cluster 3, [High Physical Activity and CRF] (highest values in CRF, handgrip strength and MVPA). Clusters 2 and 3 showed high values in screen time and industrialized food consumption. There were no differences in sleep between the 3 Clusters. ANCOVA analysis revealed that participants belonging to Cluster 3 showed significantly lower adiposity and a higher Fat Free Mass compared with the other two clusters (p < 0.05). Conclusion: Our findings suggest that a lifestyle characterized by high levels of physical activity and physical fitness and low consumption of industrialized food may be protective against the problem of obesity, which could be helpful to develop interventions to reduce excess weight in Mexican adolescents.

Mexican Parents' Beliefs About Drinking Plain Water in Front of Their Preschoolers

Because children learn habits from observing their parents, we assessed the top-of-the-mind beliefs held by parents about "drinking plain water in front of their preschool child during lunch one day this coming weekend." We recruited a convenience sample of 34 Mexican parents from daycares in Guadalajara and conducted a content analysis. Main advantage identified was getting healthier, followed by being a good example for the child. Few parents identified disadvantages. Most reported to have at least one approver within their families. The most frequent facilitator was "having it," while "not having it" was the main barrier.

Gestational diabetes mellitus and size at birth modify early adiposity accretion. Evidence from the OBESO cohort

AIM

To evaluate the association between maternal obesity, gestational diabetes (GDM), and birth size with infant fat-mass (FM) accretion from 1 to 6 months (M).

METHODS

Healthy pregnant women and their term babies from the OBESO cohort were studied (1 M-3 M, n = 122; 1 M-6 M, n = 90). Registered maternal data was: pregestational body-mass-index (preBMI), GDM (2hOGTT), medications, gestational weight gain. Macrosomia (>4000 g), large/small for gestational age (LGA/SGA)(weight/age > 90° and < 90°, respectively-WHO) were recorded at birth. Infant FM (air-displacement plethysmography) was measured (1 M, 3 M, 6 M) and FM accretion computed (ΔkgFM from 1 M-3 M and 1 M-6 M). Exclusive breastfeeding (EBF) was assessed. Adjusted-multiple linear regression models were performed.

RESULTS

PreBMI was 27.4 ± 5.2 kg/m2. GDM was present in9%(n = 11) of women; 12.3%(n = 15) of them received metformin/insulin. One newborn was LGA; 20.7%(n = 25) were SGA. From 1 M-3 M, SGA was a predictor of higher FM accretion (B:0.28, 95%CI:0.14-0.43); GDM was not associated. From 1 M-6 M, higher FM accretion was observed in SGA newborns (B:0.43, 95%CI:0.19-0.67) and GDM infants (B:0.48, 95%CI:0.06-0.89). In all models (R2 ≥ 0.48, p < 0.001), infant weight and being female were positively associated, while maternal obesity, metformin/insulin, and EBF were not.

CONCLUSIONS

GDM appears to program early higher adiposity accretion, independently of excessive fetal growth. SGA was associated with higher FM accretion in early infancy.

The influence of Chile's food labeling and advertising law and other factors on dietary and physical activity behavior of elementary students in a peripheral region: a qualitative study

BACKGROUND

In 2016, Chile implemented the Food Labeling and Advertising Law to fight childhood obesity through front-of-package food labelling, marketing restrictions and school activities and programs. Nevertheless, little is known on its influence on key stakeholders in vulnerable peripheral regions of the country. This study aimed at identifying important influencing factors including the Food Labeling and Advertising Law on dietary habits and physical activity patterns of second graders in Chile, as perceived by school representatives and the children themselves.

METHODS

Semi-structured interviews with four school directors and 17 groups of three second graders, informal interviews with 9 key teachers and 4 food services staff complemented with documented observations were carried out in four primary schools of the Chilean city of Punta Arenas, in the Magallanes Punta Arenas region. The different sources allowed for triangulation of results.

RESULTS

FLAL seems to have a negligible influence on young children's diet and physical activity in the study region. Barriers are children's deeply rooted dietary habits, excessive screen-time, the parents' lacking problem awareness, limited time for parenting practices and bad role modeling. Environmental barriers are overloaded schools due to insufficient coordination between governmental entities, lacking funds for sound teacher training and unsafe neighborhoods limiting children's play.

CONCLUSIONS

Policy interventions aimed at reducing childhood obesity need to include and empower schools, families and local communities as active partners and consider their framework conditions for greater influence on dietary habits and physical activity.

Association of total and pancreatic serum amylase enzymatic activity with insulin resistance and the glucose and insulin responses to oral starch test in Mexican children

BACKGROUND/OBJECTIVES

Little is known about the effect of serum amylase enzymatic activity on glucose metabolism. We investigated the association of serum amylase enzymatic activity with fasting plasma glucose, insulin resistance (IR), and the plasma glucose and insulin response to an oral starch test (OST) in Mexican children.

METHODS

Anthropometric data, glucose and insulin levels, and the serum enzymatic activity of total (AMYt), salivary (AMY1), and pancreatic (AMY2) amylase were analysed in 764 children (N_{normal weight}  = 427/N_obesity  = 337). After categorization into low (LA) and high (HA) AMYt, an OST with commercial white bread was performed in 39 children (N_{normal weight}  = 17/N_obesity  = 22).

RESULTS

A positive association between serum enzymatic activity of AMY2 and IR was observed in children with obesity (p = 0.018). Children with normal weight had lower plasma glucose and insulin response to OST than children with obesity (P_glucose  = 4.1 × 10^-12 ; P_insulin  = 2.1 × 10^-15 ). Compared with the LA group, children with HA showed lower plasma glucose and insulin response to OST (P_glucose  ≤ 0.040; P_insulin  ≤ 0.015).

CONCLUSION

Our results suggest that AMY2 is positively associated with IR. A high level of AMYt is related to lower glucose and insulin responses to OST in Mexican children, regardless of their weight status.

Obesity and its association with mental health among Mexican children and adolescents: systematic review

CONTEXT

Obesity and mental health issues increasingly affect children and adolescents, but whether obesity is a risk factor for mental health issues is unclear.

OBJECTIVE

To systematically review the association between obesity and mental health issues (ie, anxiety and/or depression) among Mexican children and adolescents.

DATA SOURCING, EXTRACTION, AND SYNTHESIS

A literature search of 13 databases and 1 search engine was conducted. Population, exposure, comparison, outcomes, and study design data were extracted, analyzed, and narratively synthesized. The JBI critical appraisal tool was used to evaluate evidence quality.

RESULTS

A total of 16 studies with 12 103 participants between 8 and 18 years old were included. Four studies focused on anxiety outcomes, 10 on depression, and 2 on both (ie, anxiety and depression). Evidence is unclear about the association of obesity with anxiety. However, most evidence shows that Mexican children and adolescents with overweight or obesity are more likely to have depression or report a higher number of depressive symptoms than normal-weight participants. Such likelihood is greater for females.

CONCLUSION

Health promotion interventions to treat or prevent obesity could also consider mental health outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42019154132.

Cultural factors related to childhood and adolescent obesity in Mexico: A systematic review of qualitative studies

Culture and culturally specific beliefs or practices may influence perceptions and decisions, potentially contributing to childhood obesity. The objective of this study is to identify the cultural factors (expressed through decisions, behaviors, individual experiences, perceptions, attitudes, or views) related to childhood and adolescent obesity in Mexico. Ten databases and one search engine were searched from 1995 onwards for qualitative studies. The Sunrise Enabler Model, described within the Cultural Care Theory, guided this review. Sample, the phenomenon of interest, study design, and evaluation data were extracted, and the Critical Appraisals Skills Programme tool was used to assess the quality of the included studies. Twenty-four studies were included. Of these, 12 studies included children or adolescents, 12 included parents, eight included schoolteachers, four included school staff (other than teachers), four included food vendors, and one included policymakers. Cultural values, beliefs, lifeways (especially food and food costumes), kinship, and social factors (particularly immediate and extended family) strongly influenced childhood and adolescent obesity-related lifestyles in Mexico. Most cultural factors related to childhood obesity in Mexico identified in this review may be modifiable and amenable to practical interventions.

Healthy living behaviors in youth: a comparative study in Brazil, Colombia and Mexico

The physical, mental and social well being, refers to a new concept of health, far from a conceptualisations of absence of disease Additional challenges emerge as individuals face deep social inequities depending on their ethnicity, rural residence or low educational level, as these translate to poor access to health services and more difficulties to adhere to healthy living behaviors. The objective of this study was to assess the perception that adolescents and young adults in Latinamerica have of the importance of healthy living behaviors (HLB) in the physical, emotional and lifestyle spheres. The approach is considered quantitative and descriptive with a cross sectional design. The sampling consisted of 192 young adults in Brazil, Colombia and Mexico. The results show that participants prioritize higher emotional wellbeing. They state that the health crisis changed the perception, as now the value more the emotional side of health, and understand the status of a combination of the different aspects of wellness. The Latinamerican context poses a challenge in designing strategies with a holistic health perspective, with complexities in the economic and sociocultural domains.

Impacts of an early childhood obesity prevention program in Mexico

The Healthy Change Program aimed to improve the accuracy of maternal perceptions of children's weight (MPCW), maternal feeding style (MFS) and feeding practices. Using a randomized control trial design, the intervention group received 4-weekly group sessions focusing on MPCW, MFS and healthy behaviors. The control group received the same dose of attention-control sessions on food hygiene. Data were collected at the baseline and at the end of the program via self-administered questionnaires and anthropometric measurements. Participants included 294 mother-child dyads with 149 in the intervention group and 145 in the control group. The accuracy of MPCW significantly increased at the study end point in the intervention group (57.0-67.1%, P < 0.05) but not in the control group (67.6-69.7%, P > 0.05), with no between-group difference in pre- and post-change (P > 0.05). At the study end point, more mothers of overweight and obese children in the intervention group had accurate MPCW than their control counterparts (31.4% versus 11.1%, P < 0.01). The intervention group had a shift toward an authoritative style at the study end point (17.4% versus 26.2%, P < 0.001) and favorable changes in feeding practices. The Healthy Change Program contributed to improving the accuracy of MPCW and shifts toward favorable MFS and feeding practices.

Serum lead levels and its association with overweight and obesity

BACKGROUND

Lead (Pb) exposure has been associated with cardiovascular diseases and metabolic syndrome, nevertheless its association with obesity, type 2 diabetes, and dyslipidemia markers has been little explored in Mexico. Therefore, we evaluated the association of serum Pb levels (Pb-S), with body mass index (BMI), fasting plasma glucose (FPG), total cholesterol (TC), and triglycerides (TG).

METHODS

A cross-sectional study was performed on 85 Mexican adults (57 women and 28 men). BMI was calculated, while FPG, TC, and TG were measured by the enzymatic colorimetric method. Total Pb-S levels were measured using inductively coupled plasma mass spectrometry (ICP-MS).

RESULTS

The study population was 20.3 ± 1.9 years old, showed an average of Pb-S of 0.0982 ± 0.068 μg dL^-1, and presented a frequency of overweight (OW) and obesity (OB) of 50.5% and 18.8%, respectively. Men had higher average FPG than women (Women= 83.930 ± 5.662 vs Men= 84.953 ± 6.495; p = 0.037). When we analyzed anthropometric and clinical variables, Pb-S and frequency of OW and OB were observed to increase within the categories of Pb-S tertiles (<0.001). The averages of Pb-S were 0.051 ± 0.035 µg dL^-1, 0.107 ± 0.067 µg dL^-1, and 0.151 ± 0.063 µg dL^-1 for individuals with normal weight (NW), OW, and OB, respectively. In addition, an analysis adjusted for age and sex shows Pb-S is positively associated with BMI (β = 2.76 ± 0.498, p = <0.001).

CONCLUSION

Our results evidence a significant association between Pb-S and the increase of BMI in Mexican adults and highlight the important health impact that may represent environmental Pb exposure.

Association between SNPs in Leptin Pathway Genes and Anthropometric, Biochemical, and Dietary Markers Related to Obesity

Obesity is one of the main public health problems in Mexico and the world and one from which a large number of pathologies derive. Single nucleotide polymorphisms (SNPs) of various genes have been studied and proven to contribute to the development of multiple diseases. SNPs of the leptin pathway have been associated with the control of hunger and energy expenditure as well as with obesity and type 2 diabetes mellitus. Therefore, the present work focused on determining the association between anthropometric markers and biochemical and dietary factors related to obesity and SNPs of leptin pathway genes, such as the leptin gene (LEP), the leptin receptor (LEPR), proopiomelanocortin (POMC), prohormone convertase 1 (PCSK1), and the melanocortin 4 receptor (MC4R). A population of 574 young Mexican adults of both sexes, aged 19 years old on average and without metabolic disorders previously diagnosed, underwent a complete medical and nutritional evaluation, biochemical determination, and DNA extraction from the blood; DNA samples were subsequently genotyped. Association analyses between anthropometric, biochemical, and dietary variables with SNPs were performed using binary logistic regressions (p-value = 0.05). Although the sampled population did not have previously diagnosed diseases, the evaluation results showed that 33% were overweight or obese according to BMI and 64% had non-clinically elevated levels of body fat. From the 74 SNP markers analyzed from the five previously mentioned genes, 62 showed polymorphisms within the sampled population, and only 35 of these had significant associations with clinical variables. The risk associations (OR > 1) occurred between clinical markers with elevated values for waist circumference, waist−height index, BMI, body fat percentage, glucose levels, insulin levels, HOMA-IR, triglyceride levels, cholesterol levels, LDL-c, low HDL-c, carbohydrate intake, and protein intake and SNPs of the LEP, LEPR, PCSK1, and MC4R genes. On the other hand, the protective associations (OR < 1) were associated with markers including elevated values for insulin, HOMA-IR, cholesterol, c-LDL, energy intake > 2440 Kcal/day, and lipid intake and SNPs of the LEP and LEPR genes and POMC. The present study describes associations between SNPs in leptin pathway genes, revealing positive and negative interactions between reported SNPs and the clinical markers related to obesity in a sampled Mexican population. Hence, our results open the door for the further study of new genetic variants and their influence on obesity.

The potential epidemiologic, clinical, and economic impact of requiring schools to offer Physical Education (PE) classes in Mexico City

Background

Many schools have been cutting physical education (PE) classes due to budget constraints, which raises the question of whether policymakers should require schools to offer PE classes. Evidence suggests that PE classes can help address rising physical inactivity and obesity prevalence. However, it would be helpful to determine if requiring PE is cost-effective.

Methods

We developed an agent-based model of youth in Mexico City and the impact of all schools offering PE classes on changes in weight, weight-associated health conditions and the corresponding direct and indirect costs over their lifetime.

Results

If schools offer PE without meeting guidelines and instead followed currently observed class length and time active during class, overweight and obesity prevalence decreased by 1.3% (95% CI: 1.0%-1.6%) and was cost-effective from the third-party payer and societal perspectives ($5,058 per disability-adjusted life year [DALY] averted and $5,786/DALY averted, respectively, assuming PE cost $50.3 million). When all schools offered PE classes meeting international guidelines for PE classes, overweight and obesity prevalence decreased by 3.9% (95% CI: 3.7%-4.3%) in the cohort at the end of five years compared to no PE. Long-term, this averted 3,183 and 1,081 obesity-related health conditions and deaths, respectively and averted ≥$31.5 million in direct medical costs and ≥$39.7 million in societal costs, assuming PE classes cost ≤$50.3 million over the five-year period. PE classes could cost up to $185.5 million and $89.9 million over the course of five years and still remain cost-effective and cost saving respectively, from the societal perspective.

Conclusion

Requiring PE in all schools could be cost-effective when PE class costs, on average, up to $10,340 per school annually. Further, the amount of time students are active during class is a driver of PE classes’ value (e.g., it is cost saving when PE classes meet international guidelines) suggesting the need for specific recommendations.

Interventions to Prevent Obesity in Mexican Children and Adolescents: Systematic Review

The prevalence of overweight and obesity has been rising among Mexican children and adolescents in the last decades. To systematically review obesity prevention interventions delivered to Mexican children and adolescents. Thirteen databases and one search engine were searched for evidence from 1995 to 2021. Searches were done in English and Spanish to capture relevant information. Studies with experimental designs, delivered in any setting (e.g., schools or clinics) or digital domains (e.g., social media campaigns) targeting Mexican children or adolescents (≤ 18 years) and reporting weight outcomes, were included in this review. In addition, the risk of bias was appraised with the Effective Public Health Practice Project Quality Assessment Tool. Twenty-nine studies with 19,136 participants (3-17 years old) were included. The prevalence of overweight and obesity at baseline ranged from 21 to 69%. Most of the studies (89.6%) were delivered in school settings. The duration ranged from 2 days to 3 school years, and the number of sessions also varied from 2 to 200 sessions at different intensities. Overall, anthropometric changes varied across studies. Thus, the efficacy of the included studies is heterogeneous and inconclusive among studies. Current evidence is heterogeneous and inconclusive about the efficacy of interventions to prevent obesity in Mexican children and adolescents. Interventions should not be limited to educational activities and should include different components, such as multi-settings delivery, family inclusion, and longer-term implementations. Mixed-method evaluations (including robust quantitative and qualitative approaches) could provide a deeper understanding of the effectiveness and best practices.

Association of Weight Perception, Body Satisfaction, and Weight Loss Intention With Patterns of Health Risk Behaviors in Adolescents With Overweight and Obesity

Obesity is a public health issue and childhood is a critical window in which to establish healthy eating patterns and modify risk factors for overweight. This study aims to verify the association of weight perception, body satisfaction, and weight loss intention with patterns of health risk behaviors in adolescents with overweight and obesity. We analyzed health risk behavior from a school-based national survey conducted in 2015 in Brazil (n = 2,703 students with overweight or obesity, aged 13-17 years). We performed latent class analysis of alcohol consumption, tobacco use, physical activity, screen time, and eating habits for adolescents with overweight and identified four distinct health behavior patterns. The association of these patterns with weight perception, body satisfaction, and weight loss intention was analyzed through multinomial logistic regression. Adolescents who perceived themselves as "fat" or "very fat" were more likely to have a sedentary lifestyle and low consumption of fruit and vegetables. Body satisfaction was a protective factor against sedentary lifestyle. Students who reported weight loss intention were less likely to be in high-health-risk behavior groups (low consumption of fruit and vegetables; sedentary lifestyle; tobacco and alcohol use). Self-perception as overweight had detrimental associations, while body satisfaction was a protective factor for a healthy lifestyle. Weight loss intention still requires rigorous analysis due to inconsistencies in the literature. The complexity of the relationship between body image and obesity needs to be highlighted. Multicomponent strategies are required to control the global obesity pandemic.

Changes in Sugar Sweetened Beverage Intake Are Associated with Changes in Body Composition in Mexican Adolescents: Findings from the ELEMENT Cohort

Changes in consumption of sugar sweetened beverage (SSBs) have been associated with increased body mass index (BMI), but little work has evaluated the effect on waist circumference (WC) and body fat percentage during adolescence, a period characterized by rapid growth and change in dietary behaviors. We examined the relationship of changes in SSB intake and changes in adiposity over two years in 464 Mexican adolescents. Food frequency questionnaires were used to sum intake of regular soda, coffee with sugar, tea with sugar, sweetened water with fruit, chocolate milk, corn atole, and a sweetened probiotic milk beverage. Linear regression models were used to estimate the associations of changes in SSBs with changes in BMI, body fat percentage, and WC, adjusting for sex, socioeconomic status, screen time, physical activity, age, and change in age. Adolescents who increased their daily SSB intake by >2 serving had a −2.72% higher body fat percentage (95% CI: 0.61, 4.82); a 1−2 serving increase was associated with a 2.49 cm increase (95% CI: 0.21, 4.76) in WC compared with those with no change in intake. Within an adolescent sample, changes in SSB intake were related to concomitant changes in body fat percentage and WC, but not BMI.

Comprehensive evaluation of Salud Escolar a health school program in Mexico: Rationale, design and methods

The prevalence of obesity and overweight in Mexican children and adolescents is high (greater than 30%) and lifestyle behaviors are far from achieving health recommendations. Salud Escolar is a complex cross-sectoral multi-level policy-based program in Mexico aiming to support schoolchildren healthy behaviors. We describe the rationale, design and methods for the comprehensive evaluation of Salud Escolar during its first phase of implementation. Using a mixed-methods approach and the logic model of Salud Escolar as a guide, a comprehensive evaluation involving 3 types of evaluations was designed: 1) A design evaluation before program implementation, to determine the consistency between the design of Salud Escolar and the problem to be addressed (i.e., childhood obesity), 2) An implementation evaluation to assess potential execution bottlenecks, and 3) An outcomes evaluation, to measure short-term (i.e., knowledge, attitudes and practices related to healthy eating, drinking plain water and doing regular physical activity) and intermediate outcomes (i.e., fruit and vegetable intake, water consumption and daily moderate to vigorous physical activity). This evaluation will provide essential knowledge about program design and implementation processes, which are vital for drawing robust conclusions about the effectiveness of the program. Results and lessons learned from this comprehensive evaluation will provide evidence to improve Salud Escolar program and facilitate its upscaling process and may provide relevant information for school-based programs in other places sharing socio-contextual conditions.

Changes in Weight-Related Outcomes Among Adolescents Following Consumer Price Increases of Taxed Sugar-Sweetened Beverages

IMPORTANCE

Following the implementation of a tax on sugar-sweetened beverages (SSBs) in Mexico in 2014, SSB prices increased by about 10% on average, but differently across cities. It remains unclear how observed SSB price changes are associated with adolescent weight-related outcomes.

OBJECTIVE

To compare weight-related outcomes among adolescents living in cities with differential SSB price changes before and after the SSB tax was implemented in Mexico.

DESIGN, SETTING, AND PARTICIPANTS

Associations between differential SSB price changes and changes in weight-related outcomes were examined overall and by sex among 12 654 adolescents aged 10 to 18 years born between 1999 and 2002 living in 39 cities in Mexico. Multivariate regressions with individual fixed effects were applied on longitudinal individual-level yearly clinical data (height and weight) from 2012 to 2017 collected by the Instituto Mexicano del Seguro Social (IMSS) and merged with city-level SSB price data from 2011 to 2016 collected by the National Institute of Statistics and Geography (INEGI). Data were analyzed from July 2018 to July 2021.

EXPOSURES

Yearly city-level changes in SSB prices between 2011 and 2016.

MAIN OUTCOMES AND MEASURES

Age- and sex-specific body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) percentile and indicator for overweight or obesity if BMI was at or above the 85th percentile.

RESULTS

Before 2014, 46% of 12 654 adolescents (6850 girls and 5804 boys) included in this study had obesity or overweight. The mean (SD) age was 11.38 (1.08) years. Among girls, a 10% SSB price increase was associated with a 1.3 percentage point absolute decrease (95% CI, -2.19 to -0.36; P = .008) or a 3% relative decrease in overweight or obesity prevalence within 2 years of a price change. For girls with BMI at or above the 75th percentile pretax, this price increase was associated with a 0.59 lower BMI percentile (95% CI, -1.08 to -0.10; P = .02) or a 0.67% relative decrease. Improved outcomes for girls were observed in cities where price increases were greater than 10% after the tax. No such associations were observed for boys.

CONCLUSIONS AND RELEVANCE

In this study, increased SSB prices were associated with decreased overweight or obesity prevalence among girls but not among boys. Improvements in outcomes were small, and mostly observed for girls with heavier weight and in cities where price increases after the tax were greater than 10%.

Obesity and oral health in Mexican children and adolescents: systematic review and meta-analysis

Context

A relationship between obesity and poor oral health has been reported.

Objective

To investigate the association between overweight/obesity and oral health in Mexican children and adolescents.

Data Sources

A literature search was conducted of 13 databases and 1 search engine for articles published from 1995 onward.

Data Analysis

A total of 18 publications were included. Evidence was inconclusive and varied according to sociodemographic factors or outcome measuring tools. The Decayed, Missing, and Filled Teeth and Filled Teeth Surfaces indices and the decayed extracted filled teeth index outcomes were included in a random effects model meta-analysis. Pooled estimates showed no statistically significant oral health differences (measured via the decayed extracted filled teeth or the Decayed, Missing, and Filled Teeth Surfaces indexes) among body mass index (BMI) categories. However, pooled estimates of 6 studies showed that children with higher BMI had worse oral health in permanent teeth (measured via the Decayed Missing Filled Teeth Index) than children with lower BMI (overall mean difference, –0.42; 95%CI, –0.74, –0.11).

Conclusion

Whether there is an association between poor oral health and high BMI is inconclusive; however, both co-exist among Mexican children. Therefore, health promotion and prevention efforts should address common risk factors and broader risk social determinants shared between noncommunicable diseases.

Interventions to Treat Obesity in Mexican Children and Adolescents: Systematic Review and Meta-Analysis

Context

Prevalence of overweight and obesity has been rising in the past 3 decades among Mexican children and adolescents.

Objective

To systematically review experimental studies evaluating interventions to treat obesity in Mexican children and adolescents (≤18 years old).

Data Sources

For this study, 13 databases and 1 search engine were searched.

Data Analysis

A total of 29 studies met the inclusion criteria. Overall, 2302 participants (age range, 8–16 years) from 11 states in Mexico were included. Most of the studies (n = 17 of 29) were provided in a clinical setting. A random-effect meta-analysis of 4 randomized controlled trials was conducted and a significant effect was found on body mass index reduction that favored the intervention group (−1.52; 95%CI, −2.15 to −0.89) for short-term (≤6 mo) interventions.

Conclusions

A multicomponent, multidisciplinary, and individualized intervention that includes dietary modifications, physical activity practice, behavioral strategies, and active parental involvement might help treat childhood obesity in Mexico. However, long-term results need to be produced to identify effectiveness pointers that might help establish an integrated, long-lasting care model to treat obesity.

Reduction of small dense LDL and Il-6 after intervention with Plantago psyllium in adolescents with obesity: a parallel, double blind, randomized clinical trial

Obesity can lead children and adolescents to an increased cardiovascular disease (CVD) risk. A diet supplemented with Plantago psyllium has been shown to be effective in reducing LDL-C and IL-6 in adolescents. However, there are no studies that have explored small-dense LDL (sdLDL) or HDL subclasses. The aim of this study was to evaluate the impact of a fiber dietary intervention on LDL and HDL subclasses in adolescents with obesity. In this parallel, double blind, randomized clinical trial, the participants were assigned to Plantago psyllium or placebo (10g/day for 7 weeks). We randomized 113 participants, and evaluated and analyzed 100 adolescents (50 in each group), 15 to 19 years with a body mass index of 29-34. We measured biochemical markers LDL and HDL subclasses using the Lipoprint system (Quantimetrix) and IL-6 by ELISA. Post-treatment there was a decrease in sdLDL between the groups 2.0 (0-5.0) vs 1 (0-3.0) mg/dl (p = 0.004), IL-6 median 3.32 (1.24-5.96) vs 1.76 (0.54-3.28) pg/ml, p <0.0001. There were no differences in HDL subclasses and no adverse effects were reported in either group.Conclusions: Small dense LDL and IL-6 reduced in adolescents with obesity when consuming Plantago psyllium. This may be an early good strategy for the reduction of cardiovascular disease risk in this vulnerable population.Trial registration: ISRCTN # 14180431. Date assigned 24/08/2020 What is Known: • Supplementing the diet with Plantago psyllium lowers LDL-C levels. What is New: • First evidence that soluble fiber supplementation like Plantago psyllium decreases small dense LDL particles in association with lowered IL-6, reducing the risk of cardiovascular disease in obese adolescents.

Maternal-infant nutrition and development programming of offspring appetite and obesity

In the United States and Mexico, the obesity epidemic represents a significant public health problem. Although obesity is often attributed to a Western-style, high-fat diet and decreased activity, there is now compelling evidence that this, in part, occurs because of the developmental programming effects resulting from exposure to maternal overnutrition. Human and animal studies demonstrate that maternal obesity and high-fat diet result in an increased risk for childhood and adult obesity. The potential programming effects of obesity have been partly attributed to hyperphagia, which occurs as a result of increased appetite with reduced satiety neuropeptides or neurons. However, depending on maternal nutritional status during the nursing period, the programmed hyperphagia and obesity can be exacerbated or prevented in offspring born to obese mothers. The underlying mechanism of this phenomenon likely involves the plasticity of the appetite regulatory center and thus presents an opportunity to modulate feeding and satiety regulation and break the obesity cycle.

Street Food Stand Availability, Density, and Distribution Across Income Levels in Mexico City

Street food stands (SFS) are an understudied element of the food environment. Previous SFS studies have not used a rigorous approach to document the availability, density, and distribution of SFS across neighborhood income levels and points of access in Mexico City. A random sample (n = 761) of street segments representing 20 low-, middle-, and high-income neighborhoods were assessed using geographic information system (GIS) and ground-truthing methods. All three income levels contained SFS. However, SFS availability and density were higher in middle-income neighborhoods. The distribution of SFS showed that SFS were most often found near homes, transportation centers, and worksites. SFS availability near schools may have been limited by local school policies. Additional studies are needed to further document relationships between SFS availability, density, and distribution, and current structures and processes.

Adolescent Girls With Overweight and Obesity Feel Physically Healthy and Highlight the Importance of Mental Health

INTRODUCTION

Obesity in adolescence is a significant ongoing public health problem that has not improved over the past decade.

OBJECTIVE

This descriptive qualitative study explores the perspective of female adolescents who are overweight or obese regarding their views on health and weight within the clinic setting.

METHODS

In-depth interviews were conducted with female adolescents (age 13-19 years old; BMI ≥85th percentile) from the mid-west region of the United States (N = 28). Inductive thematic analysis using Braun & Clarke's methods was utilized.

RESULTS

The findings from this study revealed that the adolescents' view of health encompasses physical, mental, and psychosocial health dimensions, and despite being overweight and obese, the participants felt healthy. Participants discussed the need to eat healthier and increase their daily physical activity, but were unable to transform this into action. Within the clinical setting, the adolescents were sensitive to weight discussions.

CONCLUSION

Results from this study can increase providers' understanding of the adolescent, increase awareness of adolescent sensitivity, and assist researchers in developing age-appropriate interventions for effective treatment and prevention of childhood obesity.

Health-Related Factors in Rural and Urban Mexican Adolescents from the State of Jalisco: The HELENA-MEX Study

Mexico shows a high prevalence of obesity in children and adolescents. Geographical location and cultural environment could play a role in the promotion of healthy lifestyles in terms of physical activity (PA), sedentary behavior (SB) and nutrition. The purpose of this study was to assess rural and urban differences in body composition (BC), physical fitness (PF), PA and nutritional status of adolescents from the state of Jalisco (Mexico). The study involved 469 students aged 13–17 years (55.0% girls) from eight high schools. BC was analyzed by bioimpedance and PF by standardized field tests. Objective measurements of PA and SB were taken in a subsample (n = 240). Energy intake (EI) was calculated from two 24h recalls. Rural residents presented a higher prevalence of overweight, waist circumference, trunk fat mass, regional fat free mass and muscle handgrip strength (all p < 0.05, η2p < 0.06). Cardiorespiratory fitness was similar among participants, whereas urban adolescents showed higher muscle power, speed-agility and flexibility scores (all p < 0.05, η2p < 0.07). Overall lifestyle behavior in urban adolescents was more sedentary (p < 0.05, η2p = 0.11). EI was similar in both locations. In conclusion, rural Mexican adolescents presented a generally lower sedentary behavior and a lower fitness and fatness profile than their urban peers.

Delivery mode-associated gut microbiota in the first 3 months of life in a country with high obesity rates: A descriptive study

Delivery methods during childbirth and their related gut microbiota profiles have important impacts on health later in life, they can contribute to the development of diseases such as obesity, whose highest prevalence rate is found among the Mexican child population. Coincidentally, Mexico has one of the highest global average annual rate increase in cesarean births (C-section). Since Mexico leads the world in childhood obesity, studying the relationship between childbirth delivery methods and gut microbiota profiles in this vulnerable population may be used to identify early risk factors for obesity in other developed and developing countries. The objective of this study is to determine the association between child delivery method and gut microbiota profiles in healthy Mexican newborns.Fecal samples of 57 term infants who participated in a randomized clinical trial in 2013 to study the safety of Agave fructans in newborns, were used in this study. DNA samples were extracted and used to characterize the microbiota composition using high-throughput 16S rRNA gene sequencing. The samples were further divided based on childbirth delivery method, as well as early diet. Gut microbiota profiles were determined and analyzed using cluster analysis followed by multiple correspondence analysis.An unusual high abundance of Proteobacteria was found in the gut microbiota of all Mexican infants studied, regardless of delivery method. Feces from infants born by C-section had low levels of Bacteroidetes, high levels of Firmicutes, especially Clostridium and Enterococcus, and a strikingly high ratio of Firmicutes/Bacteroidetes (F:B). Profiles enriched in Bacteroidetes and low F:B ratios, were strongly associated with vaginal delivery.The profile of gut microbiota associated with feces from Mexican infants born by C-section, may be added to the list of boosting factors for the worrying obesity epidemic in Mexico.

Association of AMY1A/AMY2A copy numbers and AMY1/AMY2 serum enzymatic activity with obesity in Mexican children

BACKGROUND

Mexican children are characterized by a high-starch intake diet and high prevalence of obesity.

OBJECTIVES

To investigate the association of AMY1A/AMY2A copy numbers (CNs) and AMY1/AMY2 serum enzymatic activity with childhood obesity in up to 427 and 337 Mexican cases and controls.

METHODS

Anthropometric and dietary starch intake data were collected. CN of AMY1A/AMY2A and AMY1/AMY2 serum enzymatic activity were determined using droplet digital PCR (ddPCR) and enzymatic colorimetry, respectively. An individual participant level data meta-analysis of association between AMY1A CNVs and obesity was also performed.

RESULTS

A positive association between AMY1A/AMY2A CNs and their corresponding AMY1/AMY2 serum enzyme activity was observed in children with normal weight and obesity. The serum enzyme activity of AMY1 and AMY2 was negatively associated with childhood obesity risk, and the association was restricted to kids eating medium/high amount of starch (P_interaction = .004). While no association between AMY1A and AMY2A CNs and childhood obesity was observed in our sample, we confirmed a significant association between AMY1A CN and obesity in a meta-analysis of 3100 Mexican children.

CONCLUSIONS

Our data suggest that genetically determined salivary and pancreatic amylase activity can increase/decrease the risk of obesity in Mexican children, this effect being blunted by a low-starch diet.

The Melanocortin 4 Receptor p.Ile269Asn Mutation Is Associated with Childhood and Adult Obesity in Mexicans

CONTEXT

Rare partial/complete loss-of-function mutations in the melanocortin-4 receptor (MC4R) gene are the most common cause of Mendelian obesity in European populations, but their contribution to obesity in the Mexican population is unclear.

OBJECTIVE AND DESIGN

We investigated whether deleterious mutations in MC4R contribute to obesity in Mexican children and adults.

RESULTS

We provide evidence that the MC4R p.Ile269Asn (rs79783591) mutation may have arisen in modern human populations from a founder event in native Mexicans. The MC4R Isoleucine 269 is perfectly conserved across 184 species, which suggests a critical role for the amino acid in MC4R activity. Four in silico tools (SIFT, PolyPhen-2, CADD, MutPred2) predicted a deleterious impact of the p.Ile269Asn substitution on MC4R function. The MC4R p.Ile269Asn mutation was associated with childhood (Ncontrols = 952, Ncases = 661, odds ratio (OR) = 3.06, 95% confidence interval (95%CI) [1.94-4.85]) and adult obesity (Ncontrols = 1445, Ncases = 2,487, OR = 2.58, 95%CI [1.52-4.39]). The frequency of the MC4R p.Ile269Asn mutation ranged from 0.52 to 0.59% and 1.53 to 1.59% in children and adults with normal weight and obesity, respectively. The MC4R p.Ile269Asn mutation co-segregated perfectly with obesity in 5 multigenerational Mexican pedigrees. While adults with obesity carrying the p.Ile269Asn mutation had higher BMI values than noncarriers, this trend was not observed in children. The MC4R p.Ile269Asn mutation accounted for a population attributable risk of 1.28% and 0.68% for childhood and adult obesity, respectively, in the Mexican population.

CONCLUSION

The MC4R p.Ile269Asn mutation may have emerged as a founder mutation in native Mexicans and is associated with childhood and adult obesity in the modern Mexican population.

Being obese versus trying to lose weight: Relationship with physical inactivity and soda drinking among high school students

BACKGROUND

Among adolescents, physical inactivity and unhealthy dietary habits are associated with being obese. We know little about how those are associated with trying to lose weight.

METHODS

We analyzed the 2013 Centers for Disease Control and Prevention (CDC) Youth Risk Behavior Surveillance data (N = 13,583) to examine how obesity and trying to lose weight are associated with: (1) <5 physically active days per week with ≥60 minutes physical activity; (2) playing with video computer games ≥3 hours per day on average; (3) no participation in any sports team in the past year; and (4) drinking soda ≥2 times per day. We applied survey logistic regression adjusting for age and Hispanic ethnicity, stratified by sex.

RESULTS

Both being obese (13.7%) and trying to lose weight (47.7%) are significantly associated with physical inactivity. Soda drinking was associated with being obese (odds ratio [OR] = 1.34, p = .003 for boys and OR = 1.36, p = .014 for girls); it was inversely associated trying to lose weight among girls (OR = 0.72, p < .001) but not among boys (OR = 1.13, p = .174).

CONCLUSION

Obesity was associated with physical inactivity and drinking soda in both sexes. Only girls appeared to avoid drinking soda as a strategy for losing weight. Trying to lose weight was associated with a higher likelihood of physically inactive behaviors both sexes. High schools need to develop collaborative strategies for reducing adolescent obesity and supporting students who are trying to lose weight that address physical inactivity and soda intake.

Relationship between different levels of the Mexican food environment and dietary intake: a qualitative systematic review

Objective:

To investigate the possible associations between the food environment and dietary intake in the Mexican population.

Design:

Four databases (PubMed, PsychInfo, Web of Science and SCIelo) were used to retrieve relevant articles using an open timeframe. Articles were reviewed if they contained a systematic measure (i.e. food checklist) of the food environment (e.g. food availability) and dietary intake.

Setting:

Urban and rural communities in Mexico.

Participants:

Population-based studies of Mexican communities.

Results:

Twenty studies that assessed at least one food environment level, and at least one dietary outcome, were reviewed. Findings from these studies showed that changes in the Mexican food environment seem to be associated with higher availability of energy-dense foods. Energy-dense foods can be linked to a high consumption in household, environment and community food environments. When both nutrient-dense and energy-dense foods were present, individuals were more likely to consume foods with added sugars, fats and salt options than nutrient-dense items.

Conclusions:

The various levels of the food environment (i.e. household, school, community) exposed participants to energy-dense foods. Although nutrient-dense foods were present in all three levels, individuals were more likely to consume energy-dense food items. Not all three levels of the food environment are well represented in the urban and rural settings. Most studies on the community food environment were done in rural areas, whereas most studies on the school food environment were done in urban settings. Additional rigorously designed studies are needed to document the relationship between the food environment and dietary intake in the Mexican population.

Birth weight, birth order, and age at first solid food introduction influence child growth and body composition in 6- to 8-year-old Maya children: The importance of the first 1000 days of life

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.

Short chain fatty acids could prevent fat deposition in pigs via regulating related hormones and genes

Short chain fatty acids (SCFAs) are produced when indigestible carbohydrates, such as fiber and resistant starch, undergo fermentation by specific microbiota in the hindgut.

Thinness, overweight, and obesity in indigenous school children and youth in Mexico

Background: The prevalence of overweight (OWT) and obesity (OB), defined by the body mass index (BMI, kg/m²) among children and youth has increased worldwide in the last 30-40 years.Aim: To evaluate the weight status, defined by the BMI, of indigenous school children and youth resident in different regions of MexicoSubjects and methods: Students 6-18 years (31,448 boys, 27,306 girls) were enrolled in bilingual schools for indigenous children and youth in Mexico in 2012. Height and weight were measured; the BMI was calculated. The BMI of each student was classified relative to International Obesity Task Force (IOTF) age- and sex-specific criteria as thin (three grades), normal, overweight (OWT) or obese (OB). The sample was divided into five geographic regions for analysis: North, Central, South-Gulf, South-Pacific, and South-Southeast. Age- and sex-specific prevalence, 95% confidence intervals, and Chi-square tests were calculated.Results: Prevalence of OWT + OB was highest in the South-Gulf, South-Pacific and South-Southeast regions and lowest in the North and Central regions, while thinness was most prevalent in the North and Central regions.Conclusion: Prevalence of severe and moderate thinness was relatively low, while the combined prevalence of OWT + OB was generally more prevalent in indigenous boys than girls. However, the prevalence of thinness, OWT + OB among indigenous children and youth was lower than in the general population of children and youth in Mexico.

Cultural Influences on Childhood Obesity in Ethnic Minorities: A Qualitative Systematic Review

Introduction: Childhood obesity remains an unrelenting public health problem disproportionately affecting ethnic minorities. Although research has examined ethnicity as a factor of childhood obesity, few studies have examined cultural influences. The purpose of this systematic review was to examine the qualitative evidence of cultural influences on childhood obesity in ethnic minority groups. Methodology: Selective sampling of studies since 2008 yielded 251 articles. Twelve articles that addressed cultural influences on childhood obesity were identified for review. The Culture Care Theory Sunrise Enabler factors were used as an a priori framework for theme coding. Results: Nine themes emerged: child feeding, family, gender roles, food, healthy child appearance, physical activity, sedentary activity, food cost, and obesogenic environment. Discussion: Cultural care practices such as traditional foods and family meals are protective factors in childhood obesity and should be encouraged by nurses caring for and working with ethnic minority populations.

Childhood obesity in Mexico: A critical analysis of the environmental factors, behaviours and discourses contributing to the epidemic

Mexico has the highest prevalence globally for children who are overweight. We conducted a qualitative study to understand childhood obesity in Mexico and the complex factors at play. Data were collected at three elementary schools in a low socio-economic area in Mexico City. Semi-structured interviews were conducted with 60 children, 24 parents and 28 teachers. The children interviewed were between the ages of 8 and 12 years old. Interview texts were analysed using NVivo 9 and 10 and thematic discourse analysis was used. Findings revealed how children’s choices around nutrition and physical activity were constrained by their environment and discursive constructions.

Greenspace, physical activity, and BMI in children from two cities in northern Mexico

Numerous previous studies have reported positive associations between exposure to greenspace and children's physical activity, but in high-income countries only. Prior studies have also examined greenspace and obesity in children, but these have yielded inconsistent results and focused mostly on older children. The purpose of this study was to assess associations between time children spent in greenspace as the primary exposure and our outcomes of interest, including 1) minutes of physical activity, and 2) body mass index (BMI) z-score. Our sample was 102 children ages 3 to 5 years living in Ensenada and Tijuana, Mexico. We fit linear mixed models to estimate associations between greenspace and children's physical activity and BMI z-score. After adjustment for potential confounders, greater time in greenspace was associated with decreased sedentary time (−0.08 min per hour for each additional 30 min in greenspace; 95% CI −0.13, −0.04; p = 0.002) and increased moderate-to-vigorous physical activity (MVPA) (0.06; 95% CI 0.03, 0.10; p < 0.001). Results were driven primarily by children in Tijuana (−0.22; 95% CI −0.38, −0.06; p = 0.008 for sedentary time and 0.15; 95% CI 0.06, 0.38; p = 0.007 for MVPA). Time in greenspace was not associated with BMI z-score in children in Ensenada (0.001; 95% CI −0.008, 0.01; p = 0.83) or Tijuana (−0.009; 95% CI −0.02, 0.004; p = 0.17). Greater time in greenspace was associated with physical activity but not BMI in our sample of children—more so in Tijuana compared to Ensenada. Given high rates of obesity, interventions should aim to increase physical activity in young children in Northern Mexico.

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Greater time in greenspace was associated with decreased sedentary time.

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Greater time in greenspace was associated with increased physical activity.

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Associations were mainly driven by children in Tijuana compared to Ensenada.

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Time spent in greenspace was not associated with body mass index z-score.

Adiponectin is associated with cardio-metabolic traits in Mexican children

The adipocyte-derived adiponectin hormone bridges obesity and its cardio-metabolic complications. Genetic variants at the ADIPOQ locus, in ADIPOR1, and ADIPOR2 have been associated with adiponectin concentrations and cardio-metabolic complications in diverse ethnicities. However, no studies have examined these associations in Mexican children. We recruited 1 457 Mexican children from Mexico City. Six genetic variants in or near ADIPOQ (rs182052, rs2241766, rs266729, rs822393), ADIPOR1 (rs10920533), and ADIPOR2 (rs11061971) were genotyped. Associations between serum adiponectin, genetic variants, and cardio-metabolic traits were assessed using linear and logistic regressions adjusted for age, sex, and recruitment center. Serum adiponectin concentration was negatively associated with body mass index, waist to hip ratio, low-density lipoprotein cholesterol, total cholesterol, triglycerides, fasting glucose, fasting insulin, homeostatic model assessment of insulin resistance, dyslipidemia and overweight/obesity status (7.76 × 10⁻⁴⁰ ≤ p ≤ 3.00 × 10⁻³). No significant associations between genetic variants in ADIPOQ, ADIPOR1, and ADIPOR2 and serum adiponectin concentration were identified (all p ≥ 0.30). No significant associations between the six genetic variants and cardio-metabolic traits were observed after Bonferroni correction (all p < 6.9 × 10⁻⁴). Our study suggests strong associations between circulating adiponectin concentration and cardio-metabolic traits in Mexican children.

Compliance with nutrition standards in Mexican schools and their effectiveness: a repeated cross-sectional study

BACKGROUND

Mexico approved mandatory nutrient-based standards for foods sold in schools in 2011. The aim of this study was to analyse the association between compliance with nutrition standards for foods sold in schools and children's school snacks.

METHODS

Data came from three surveys representative of Mexican elementary schools in 13 states and their students (2012, 2013 and 2015); n = 645 children from N = 99 different schools. Information on foods sold in schools and snacks consumed by children was collected through direct observation. Compliance with the standards was defined as the proportion of foods sold in school which met nutrition criteria established by the standards. Snacks were classified as healthy if they contained at least one fruit or vegetable and had no sugar-sweetened beverages. Robust logistic regression models for cross-sectional and repeated surveys aggregated at the school-level were fitted to quantify the association between school compliance with standards and healthy snacks.

RESULTS

On average across waves 27% of foods sold complied with nutrition standards; 18% of children consumed a healthy snack. For snacks purchased in school, a 10% increase in school compliance with the standards was associated with a 32% increase in the odds of a healthy snack (OR = 1.32; 95%CI 1.09,1.61); no association was observed for snacks brought from home. The odds of a healthy snack increased over time in schools where compliance with the standards improved (OR = 3.89; 95%CI 1.47,10.31) but not in those where compliance remained constant or decreased.

CONCLUSIONS

Only a small proportion of children are eating healthy snacks in school. School compliance with standards increases the likelihood of a healthy snack if it is bought at school. Our findings support better implementation of the standards and additional strategies to enhance the policy to achieve its aim of reducing childhood obesity.

The gut microbiome of Mexican children affected by obesity

Obesity is a metabolic disorder and global health issue. In Mexico 34.4% of children between 5 and 11 years-old are overweight or obese. Here we address this issue studying the gut microbiome in a sample of Mexican children affected by obesity. We performed metagenomic shotgun-sequencing of DNA isolated from fecal samples from a cohort of normal weight and obese Mexican children using Illumina platform with HiSeq 2500. We also examined their metabolic factors and fecal short-chain fatty acids concentration. The results show that a remarkable dysbiosis of bacteria, archaea and viruses was not observed in the obese children group compared to the normal weight group; however, the archaeal community exhibited an increase of unclassified Methanobrevibacter spp. in obese children. The bacterial communities of all participants were clustered into three different enterotypes. Most normal weight children have a gut bacterial community dominated by Ruminococcus spp. (Enterotype 3), while most obese children had a community dominated by Prevotella spp. (Enterotype 2). On the other hand, changes in the gut microbiome were correlated with clinical metadata and could be used to stratify individuals based on their phenotype. The species Megamonas spp. were over-represented in obese children, whereas members of the family Oscillospiraceae were depleted in the same individuals and negatively correlated with levels of serum cholesterol. A microbiome comparative metabolic pathway analysis showed that two KEGG pathway modules of glycolysis, Glycolysis I (from Glucose 6-Phosphate), and Glycolysis II (from Fructose 6-Phosphate) were significantly overrepresented in normal weight children. Our results establish specific alterations in the gut microbiome of Mexican children affected of obesity, along with clinical alterations, providing information on the microbiome composition that may be useful for prognosis, diagnosis, and treatment.

Sobrepeso y obesidad en niños y adolescentes en México,actualización de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016

 Objetivo. Actualizar las prevalencias de sobrepeso y obe­sidad (SP+O) y estudiar algunos determinantes asociados en población<20 años, de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016 (Ensanut MC 2016). Ma­terial y métodos. La Ensanut MC 2016 es una encuesta nacional probabilística. Se estimó el puntaje Z del índice de masa corporal. Se clasificó el riesgo de sobrepeso, sobrepe­so y obesidad de acuerdo con el patrón de referencia de la OMS. Se estudiaron variables sociodemográficas asociadas con sobrepeso mediante regresión logística. Resultados. La prevalencia nacional de SP+O en <5 años fue niñas 5.8%, niños 6.5%; escolares niñas 32.8%, niños 33.7%; adolescentes mujeres 39.2% y hombres 33.5%. Las mujeres adolescentes de localidades rurales mostraron un incremento de 2012 a 2016 de 9.5 puntos porcentuales. Conclusiones. La prevalencia de SP+O en niñas y mujeres en zonas rurales muestran un aumento importante en un periodo corto, lo que llama a implementar acciones de atención inmediatas.

ACE, APOA5, and MTP Gene Polymorphisms Analysis in Relation to Triglyceride and Insulin Levels in Pediatric Patients

BACKGROUND AND AIMS

Obesity is a complex, chronic, and multifactorial disease that has become a major, and worldwide, public health problem contributing to an increased number of pathologies, including type 2 diabetes, cardiovascular disease, hyperlipidemia, and metabolic syndrome, thus suggesting a commolon origin. A diet high in sugar and fats coupled with a sedentary lifestyle has a major role in the development of obesity. However, the genetic background has also been associated with body fat accumulation. The aim of this study was to assess the effect ofACE-rs4646994, APOA5-rs662799, and MTP-rs1800591 gene polymorphisms on clinical and biochemical parameters and to evaluate the association with body phenotypes in children and adolescent population of Saltillo, Coahuila, Mexico.

METHODS

Anthropometric, clinical, biochemical parameters and BMI were obtained from 405 children and adolescents. The BMI was used to determine the body phenotype. The rs4646994 gene polymorphism was determined by PCR, whereas rs662799 and rs1800591 were determined by PCR-RFLP. The obtained results were analyzed to determine their association of these single nucleotide polymorphisms with body phenotype and biochemical parameters.

RESULTS

TT genotype for APOA5-rs662799 was associated with increased levels of HDL-C in the analyzed population (p <0.05). The ACErs4646994gene polymorphism is associated with high Insulin levels, HOMAIR index, and triglyceride levels, mainly when presenting a I/I genotype (p <0.05).

CONCLUSION

The polymorphic allele of the ACE gene is capable of modulating triglyceride levels, insulin levels and HOMA-IR index in the evaluated population; it must be highlighted that this has not been reported in other studied populations elsewhere.

Genetic contribution to waist-to-hip ratio in Mexican children and adolescents based on 12 loci validated in European adults

BACKGROUND/OBJECTIVES

The prevalence of abdominal obesity in Mexican children has risen dramatically in the past decade. Genome-wide association studies (GWAS) for waist-to-hip ratio (WHR) performed predominantly in European descent adult  populations have identified multiple single-nucleotide polymorphisms (SNPs) with larger effects in women. The contribution of these SNPs to WHR in non-European children is unknown.

SUBJECTS/METHODS

Mexican children and adolescents (N = 1421, 5-17 years) were recruited in Mexico City. Twelve GWAS SNPs were genotyped using TaqMan Open Array and analyzed individually and as a gene score (GS).

RESULTS

Mexican boys and girls displayed 2.81 ± 0.29 and 3.10 ± 0.31 WHR standard deviations higher than children and adolescents from the United States. WHR was positively associated with TG (β = 0.733 ± 0.190, P = 1.1 × 10^-4) and LDL-C (β = 0.491 ± 0.203, P = 1.6 × 10^-2), and negatively associated with HDL-C (β = -0.652 ± 0.195, P = 8.0 × 10^-4), independently of body mass index. The effect allele frequency (EAF) of 8 of 12 (67%) SNPs differed significantly (P < 4.17 × 10^-3) in Mexican children and European adults, with no evidence of effect allele enrichment in both populations (4 depleted and 4 enriched; binomial test, P = 1). Ten out of 12 SNPs (83.3%) had effects that were directionally consistent with those reported in GWAS (P = 0.04). HOXC13 rs1443512 displayed the best fit when modeled recessively, and was significantly associated with WHR under a recessive mode of inheritance (β = 0.140 ± 0.06, P = 2.3 × 10^-2). Significant interactions with sex were also observed for HOXC13 rs1443512 and the GS on WHR (P = 2.2 × 10^-2 and 1.2 × 10^-2, respectively). HOXC13 rs1443512 (β = 0.022 ± 0.012, P = 4.7 × 10^-2) and the GS (β = 0.007 ± 0.003, P = 7.0 × 10^-3) were significantly associated with WHR in girls only.

CONCLUSIONS

This study demonstrates that Mexican children are at high risk for abdominal obesity and detrimental lipid profiles. Our data support a partial transferability of sex-specific European GWAS WHR association signals in children and adolescents from the admixed Mexican population.

Effect of body weight and behavioural factors on caries severity in Mexican rural and urban adolescents

OBJECTIVES

To investigate if, in Mexican adolescents, body weight and caries severity are associated, and if this association differs between rural and urban populations.

METHODS

Adolescents from the rural area of Tepancan and the city of Veracruz were enrolled. Caries was recorded using the International Caries Detection and Assessment System and the body mass index (BMI) was calculated. Oral habits (toothbrushing, flossing, dental check-ups) and dietary patterns (sweets intake) were assessed. A dummy variable between BMI and living area (BMI/Area) was generated. Data were analysed using STATA and a multinomial logistic regression model was run, using caries severity as the dependent variable.

RESULTS

Four-hundred and sixty-four subjects, 12-15 years of age, participated (rural = 240; urban = 224). The BMI and area of residence were significantly associated (χ² = 12.59, P < 0.01). Area was also associated with caries severity (χ² = 24.23, P < 0.01), with the highest number of caries in dentine recorded in participants from the rural area. The dummy variable BMI/Area was related to caries severity (χ² = 27.47, P < 0.01): overweight adolescents with caries in dentine were most frequently found in the rural area. A higher prevalence of caries in enamel and a lower prevalence of caries in dentine (P < 0.01) were recorded in adolescents from the urban area, where better oral habits, but higher sweets intake (P = 0.04), were encountered. According to the multinomial logistic regression model, BMI/Area was significantly associated with caries severity (P < 0.01).

CONCLUSIONS

Overweight was not associated with caries severity in the overall population, but it became a statistically significant risk indicator in adolescents living in the rural area.

Association of Urinary Activity of MMP-2 with Microalbuminuria in an Isolated Sample of Subjects Living in High Altitude Rural Locations in México

Hernández-Hernández, Magda Elena, Jaime Morales-Romero, Clara Luz Sampieri, Diego Jesús Luna Lozano, Isidra del Carmen Valencia Lezama, Mónica Janett Muñoz Contreras, and Arturo Rodríguez Hernández. Association of urinary activity of MMP-2 with microalbuminuria in an isolated sample of subjects living in high altitude rural locations in México. High Alt Med Biol. 18:209-218, 2017.-Matrix metalloproteinases (MMP) are implicated in remodeling of the renal extracellular matrix. In a cross-sectional study we evaluated renal impairment in general population of high-altitude rural locations in México. Multivariable analysis was performed to identify the association between MMP-2 and MMP-9 and microalbuminuria. Twenty-eight (20.9%) subjects with renal impairment (WRI) and 106 (79.1%) without renal impairment were included. No differences were found relating to sex, location, marital status, current habits, weight, height, body mass index, waist size in males, creatinine in males, and uric acid. In contrast, differences were found among age, level of education, waist size in general and in females, creatinine in general and in females, urinary albumin, urea, glucose, total cholesterol, and triglycerides. Proportions of hypertension, type 2 diabetes mellitus, central abdominal obesity, hypertriglyceridemia, and hypercholesterolemia were greater in the group WRI. Presence of urinary MMP-2 or of both urinary gelatinases and arbitrary unit (AU) values ≥P₉₀ were associated with microalbuminuria. We conclude that AU values ≥P₉₀ of urinary MMP-2 (OR = 20.1, p = 0.002) is associated with microalbuminuria.

Perceived barriers to achieving a healthy weight: a qualitative study using focus groups at public and private schools in Guatemala City

BACKGROUND

Overweight prevalence among Guatemalan girls is higher in public than in private schools. Little is known about adolescent girls' perceptions of the right ways to achieve a healthy weight. This study examines public and private school adolescent girls' perceptions of a "healthy weight," and barriers and facilitators to achieving it.

METHODS

We conducted 4 focus groups in public and private schools in Guatemala City with girls from 13 to 15 years old. The discussion guide included open-ended questions and activities aimed at examining perceptions of "healthy weight" and barriers and motivators to achieving it within the school environment. Focus groups were audio-recorded and transcribed. Data analyses followed established methods of content analysis.

RESULTS

Twenty-eight girls (private school, n = 12; public school, n = 16) of ages ranging from 13.1 to 15.9 years (median, 14, IQR, 13.6-14.9) participated in the study. Girls identified images of thin and fit women as healthy. They cited healthy eating and physical activity as ways to achieve a healthy weight. Within the school environment, barriers to maintaining a healthy weight included a lack of healthy food options and the prioritization of sports for boys over girls. In public schools, facilities were less than optimal; in private schools, girls' access to facilities was limited. Public school girls stated that their uniforms were inappropriate for exercising.

CONCLUSION

Our findings support the need to provide more healthy food options in Guatemalan schools. In addition, physical activity for girls should be promoted and facilities made available for their use.