Pre-pregnancy body mass index and gestational weight-gain predict maternal hemoglobin levels and are jointly associated with neonatal outcomes in a Mexican birth cohort.

Introduction: Introduction: there is scarce evidence of the effects of obesity and gestational weight- gain (GWG) on hemoglobin (Hb) levels in pregnancy. Little is known about the implications in offspring when pregnant mothers present with both at delivery. Aim: to identify if pre-pregnancy body mass index (BMI) and GWG are associated with Hb levels at pregnancy third trimester; and identify if the BMI status plus anemia at delivery could influence offspring anthropometry. Methods: in a sub-sample of pregnant women (n = 108) and their offspring (n = 63) from a Mexican birth cohort, information from medical files and questionnaires were used to obtain pre-pregnancy BMI (categorized as normal, overweight, and obese), GWG, and Hb during pregnancy; at delivery and postpartum anthropometric measures were obtained for offspring. Adjusted regression models predicted Hb levels according to pre-pregnancy BMI and GWG; offspring growth trajectories from birth to 3 months old were compared according to mother´s BMI status and anemia combinations at delivery. Results: pre-pregnancy normal (N), overweight (OV), and obesity (OB) were present in 48 %, 40 %, and 12 % of the participants, respectively. Anemia was detected in 22.8 % of the participants at third trimester. Hb levels in the third trimester were significantly lower in those with pre-pregnancy OB-BMI and excessive GWG (12.1 g/dL, 95 % CI: 10.7-13.5) compared to those with pre-pregnancy OB-BMI and insufficient GWG (13.3g/dL, 95 %CI: 11.9-14.8) (p = 0.04). At delivery, 11 % presented with OB-BMI and anemia. Women with OB-BMI and normal Hb levels had children with higher scores in Weight-for-Length-Z score and triceps skinfold. Conclusion: among OB women, excessive GWG was associated with having lower Hb levels in the third trimester. Newborns had higher scores in growth patterns related to adiposity from birth to 3 months old if mothers had normal Hb levels and OB.

Introducción: Introducción: existe escasa evidencia de los efectos de obesidad y ganancia de peso gestacional (GPG) y niveles de hemoglobina (Hb) durante el embarazo. Poco se conoce sobre las implicaciones en la descendencia cuando las embarazadas presentan ambos en el momento del parto. Objetivos: identificar si el índice de masa corporal (IMC) previo al embarazo y el GPG están asociados con los niveles de Hb en el tercer trimestre del embarazo; e identificar si el IMC más la anemia en el momento del parto podrían influir en la antropometría de la descendencia. Metodología: se utilizó información de expedientes médicos y cuestionarios para obtener el IMC antes del embarazo (categorizado como normal, con sobrepeso y obesidad), GPG y Hb durante el embarazo; en el momento del parto y posparto se obtuvieron medidas antropométricas para la descendencia de una submuestra de mujeres embarazadas (n = 108) y su descendencia (n = 63) de una cohorte mexicana. Los modelos de regresión ajustados predijeron los niveles de Hb según IMC y GPG antes del embarazo; se compararon las trayectorias de crecimiento de la descendencia desde el nacimiento hasta los 3 meses de edad según el estado de IMC de la madre y las combinaciones de anemia en el momento del parto. Resultados: peso preembarazo normal (N), sobrepeso (SP) y obesidad (OB) estuvieron presentes en 48 %, 40 % y 12 % de las participantes, respectivamente. Se diagnosticó anemia en el 22,8 % de las participantes en el tercer trimestre. Los niveles de Hb en el tercer trimestre fueron significativamente más bajos en aquellas con IMC-OB antes del embarazo y GPG excesivo (12,1 g/dL, IC del 95 %: 10,7-13,5) en comparación con aquellas con IMC-OB antes del embarazo y GPG insuficiente (13,3 g/dl, IC del 95 %: 11,9-14,8) (p = 0,04). Al momento del parto, el 11 % presentó OB-BMI y anemia. Las mujeres con OB-BMI y niveles normales de Hb tenían hijos con puntuaciones más altas en puntuación Z de peso para longitud y pliegue cutáneo del tríceps. Conclusión: la GPG excesiva entre las mujeres OB se asoció con niveles más bajos de Hb en el tercer trimestre. Los recién nacidos tenían puntajes más altos en los patrones de crecimiento relacionados con la adiposidad desde el nacimiento hasta los 3 meses de edad si las madres tenían niveles normales de Hb y OB.

Pre-pregnancy body mass index and gestational weight-gain predict maternal hemoglobin levels and are jointly associated with neonatal outcomes in a Mexican birth cohort / Índice de masa corporal y ganancia de peso durante el embarazo como predictores de niveles de hemoglobina materna y su asociación con desenlaces neonatales en una cohorte mexicana

Introduction: there is scarce evidence of the effects of obesity and gestational weight- gain (GWG) on hemoglobin (Hb) levels in pregnancy. Little is known about the implications in offspring when pregnant mothers present with both at delivery. Aim: to identify if pre-pregnancy body mass index (BMI) and GWG are associated with Hb levels at pregnancy third trimester; and identify if the BMI status plus anemia at delivery could influence offspring anthropometry. Methods: in a sub-sample of pregnant women (n = 108) and their offspring (n = 63) from a Mexican birth cohort, information from medical files and questionnaires were used to obtain pre-pregnancy BMI (categorized as normal, overweight, and obese), GWG, and Hb during pregnancy; at delivery and postpartum anthropometric measures were obtained for offspring. Adjusted regression models predicted Hb levels according to pre-pregnancy BMI and GWG; offspring growth trajectories from birth to 3 months old were compared according to mother´s BMI status and anemia combinations at delivery. Results: pre-pregnancy normal (N), overweight (OV), and obesity (OB) were present in 48 %, 40 %, and 12 % of the participants, respectively. Anemia was detected in 22.8 % of the participants at third trimester. Hb levels in the third trimester were significantly lower in those with pre-pregnancy OB-BMI and excessive GWG (12.1 g/dL, 95 % CI: 10.7-13.5) compared to those with pre-pregnancy OB-BMI and insufficient GWG (13.3g/dL, 95 %CI: 11.9-14.8) (p = 0.04). At delivery, 11 % presented with OB-BMI and anemia. Women with OB-BMI and normal Hb levels had children with higher scores in Weight-for-Length-Z score and triceps skinfold. Conclusion: among OB women, excessive GWG was associated with having lower Hb levels in the third trimester. Newborns had higher scores in growth patterns related to adiposity from birth to 3 months old if mothers had normal Hb levels and OB (AU)

Introducción: existe escasa evidencia de los efectos de obesidad y ganancia de peso gestacional (GPG) y niveles de hemoglobina (Hb) durante el embarazo. Poco se conoce sobre las implicaciones en la descendencia cuando las embarazadas presentan ambos en el momento del parto. Objetivos: identificar si el índice de masa corporal (IMC) previo al embarazo y el GPG están asociados con los niveles de Hb en el tercer trimestre del embarazo; e identificar si el IMC más la anemia en el momento del parto podrían influir en la antropometría de la descendencia. Metodología: se utilizó información de expedientes médicos y cuestionarios para obtener el IMC antes del embarazo (categorizado como normal, con sobrepeso y obesidad), GPG y Hb durante el embarazo; en el momento del parto y posparto se obtuvieron medidas antropométricas para la descendencia de una submuestra de mujeres embarazadas (n = 108) y su descendencia (n = 63) de una cohorte mexicana. Los modelos de regresión ajustados predijeron los niveles de Hb según IMC y GPG antes del embarazo; se compararon las trayectorias de crecimiento de la descendencia desde el nacimiento hasta los 3 meses de edad según el estado de IMC de la madre y las combinaciones de anemia en el momento del parto. Resultados: peso preembarazo normal (N), sobrepeso (SP) y obesidad (OB) estuvieron presentes en 48 %, 40 % y 12 % de las participantes, respectivamente. Se diagnosticó anemia en el 22,8 % de las participantes en el tercer trimestre. Los niveles de Hb en el tercer trimestre fueron significativamente más bajos en aquellas con IMC-OB antes del embarazo y GPG excesivo (12,1 g/dL, IC del 95 %: 10,7-13,5) en comparación con aquellas con IMC-OB antes del embarazo y GPG insuficiente (13,3 g/dl, IC del 95 %: 11,9-14,8) (p = 0,04). Al momento del parto, el 11 % presentó OB-BMI y anemia. Las mujeres con OB-BMI y niveles normales de Hb tenían hijos con puntuaciones más altas en puntuación Z de peso para longitud y pliegue cutáneo del tríceps (AU)

The overlooked paradox of the coexistence of overweight/obesity and anemia during pregnancy.

Globally, the prevalence of overweight and obesity, including among pregnant women, has substantially increased in the past three decades. This has been fueled by, among other factors, an increase in the consumption of high energy-dense foods and a decrease in physical activity. Additionally, global prevalence of anemia among pregnant women remains a public health concern. Overweight/obesity as well as anemia in pregnancy are independently associated with adverse health outcomes for the mother and offspring. In some pregnant women, the two conditions coexist. Yet current knowledge in this field, including prevalence rates, risk factors, and health consequences for mother and offspring being exposed to these conditions, is staggeringly sparse. In this review we describe the current evidence on prevalence rates, risk factors, and effects for mother and offspring regarding coexistence of overweight/obesity and anaemia in pregnant women based on a systematic literature search. We also highlight research gaps and suggest avenues for future research.

Magnitud y tendencia de la desnutrición y factores asociados con baja talla en niños menores de cinco años en México, Ensanut 2018-19.

Objetivos. Actualizar la prevalencia de desnutrición y sus tendencias en los últimos 30 años e identificar factores asociados con la baja talla en una muestra representativa nacional de niños <5 años en México. Material y méto-dos. Se estimaron prevalencias de desnutrición en <5 años en 2018-19 y se compararon con prevalencias de los últimos 30 años. Se estudiaron asociaciones de factores geográficos, del hogar, maternos e individuales con baja talla, utilizando regresión logística múltiple. Resultados. El 4.8% de los <5 años presentó bajo peso, 14.2% baja talla y 1.4% emaciación. Entre 1988-2012 hubo un descenso en baja talla interrum-pido entre 2012-2018. La baja talla se asoció positivamente con residencia rural, región sur, hogares más pobres, madres indígenas y mayor número de hijos, y negativamente con diversidad dietética. Conclusiones. La desnutrición cró-nica es un problema persistente asociado con factores de vulnerabilidad social, cuya tendencia descendente de 30 años se interrumpió entre 2012-2018. Es imperativo implementar una estrategia nacional de prevención de baja talla.

Parental Feeding Styles and Their Association With Complementary Feeding Practices and Growth in Mexican Children.

Background: Complementary feeding practices and corresponding parental feeding styles influence nutritional status in later stages of childhood. Findings on the association of these variables with infant growth remain inconsistent; in Mexico, a research gap exists in this area. Research Aims: (1) To characterize parental feeding styles and complementary feeding practices, and (2) to evaluate the association of parental feeding styles with complementary feeding practices and infant growth at 6 and 9 months of age. Methods: Data were collected from a prospective Mexican birth cohort. Parental feeding styles, complementary feeding practices, and anthropometric data from 263 to 234 mother-child pairs (infants of 6 and 9 months of age, respectively) were analyzed. Logistic and linear regression models were used to determine the associations between variables. Results: The predominant parental feeding style was the "responsive style" (90%). Only 43.7 and 8.1% of 6- and 9-month-old infants, had adequate complementary feeding practices, respectively. At 6 months, mothers who were responsive to satiety signals had 11% lesser possibilities (OR = 0.89, 95% CI [0.80, 0.98]) of their infant having inadequate complementary feeding practices than their counterparts and "pressuring to finish" and "pressuring to eat cereal" sub-constructs were associated with lower weight for length and body mass index Z-scores (p = 0.02). Conclusions: A high proportion of infants (>40%) did not meet international recommendations. The "pressuring" parental feeding style sub-constructs were associated with growth indicators in 6-month old infants. This emphasizes the importance of promoting parental responsiveness to infant appetite and satiety signals to achieving adequate complementary feeding practices.

Dietary patterns and diet quality during pregnancy and low birthweight: The PRINCESA cohort.

Although the isolated effects of several specific nutrients have been examined, little is known about the relationship between overall maternal diet during pregnancy and fetal development and growth. This study evaluates the association between maternal diet and low birthweight (LBW) in 660 pregnant women from the Pregnancy Research on Inflammation, Nutrition,& City Environment: Systematic Analyses (PRINCESA) cohort in Mexico City. Using prior day dietary intake reported at multiple prenatal visits, diet was assessed prospectively using a priori (Maternal Diet Quality Score [MDQS]) and a posteriori (dietary patterns extracted by factor analysis) approaches. The association between maternal diet and LBW was investigated by logistic regression, controlling for confounders. Adherence to recommended guidelines (higher MDQS) was associated with a reduced risk of LBW (OR, 0.22; 95% confidence interval [0.06, 0.75], P < .05, N = 49) compared with the lowest adherence category (reference group), controlling for maternal age, education, height, marital status, pre-pregnancy body mass index, parity, energy intake, gestational weight gain, and preterm versus term birth; a posteriori dietary patterns were not associated with LBW risk. Higher adherence to MDQS was associated with a lower risk of having an LBW baby in this sample. Our results support the role of advocating a healthy overall diet, versus individual foods or nutrients, in preventing LBW.

Gestational weight gain trajectories over pregnancy and their association with maternal diet quality: Results from the PRINCESA cohort.

OBJECTIVE: The aims of this study were to characterize, among pregnant Mexican women, gestational weight gain (GWG) trajectories; assess associations of maternal dietary quality score (MDQS) with GWG during early-mid pregnancy, middle pregnancy, late pregnancy, and prolonged pregnancy; and evaluate the association between MDQS and adequacy of GWG, throughout pregnancy. We hypothesized that higher MDQS adherence is protective against insufficient or excessive GWG across pregnancy and that the association between MDQS adherence and GWG would vary by prepregnancy body mass index (BMI) category. METHODS: We analyzed data from 660 pregnant women participating in the PRINCESA (Pregnancy Research on Inflammation, Nutrition and City Environments: Systematic Analyses) cohort in Mexico City, 2009 to 2014. Repeated measures of dietary intake and mother's weight were obtained during pregnancy. Individual GWG trajectories were modeled in a multilevel regression framework. Associations between MDQS (low, medium, and high adherence) and GWG were investigated using mixed-effect regression models with linear splines. RESULTS: Women with prepregnancy BMI of ≥30 kg/m2 had a slower rate of GWG (RGWG) compared with other categories. A higher adherence to MDQS was protective against an insufficient (odds ratio [OR], 0.63; 95% confidence interval [CI], 0.42-0.95; P = 0.03) and an excessive RGWG (OR, 0.62; 95% CI, 0.41-0.94; P = 0.03) throughout pregnancy, adjusting for prepregnancy BMI, energy intake, maternal age, educational level, parity, fetal sex, marital status, and physical activity. Associations between diet and RGWG differed by gestational period. CONCLUSION: A better quality diet, as measured by MDQS, was associated with appropriate GWG during pregnancy in the PRINCESA cohort.

Desarrollo de la capacidad para la regulación en salud en México.

La Academia Nacional de Medicina es un espacio esencial para discutir la ciencia de la regulación en salud y posicionar su impacto en la salud y la economía. Enmarcada dentro de la función rectora de la autoridad sanitaria, la regulación en salud es la acción de proteger a la población de los peligros sanitarios involuntarios contra los cuales el individuo no puede protegerse; es una función esencial de la salud pública, componente institucional del sistema de salud y, por ende, vinculada a sus reformas y a la cobertura universal. La regulación tiene sustento en un cuerpo teórico epidemiológico, organizacional, legal, sociológico y económico. Tiene un cuerpo metodológico que sustenta su proceso en el análisis de riesgos y se traduce en normas, implementaciones, cumplimiento, monitoreo y evaluación de la regulación. Tiene una arquitectura profesional, financiera, organizacional, legal y de gobernanza. Dada su acción universal tiene un impacto generalizado en la población y un sustancial efecto económico, influyendo en al menos 17 % del comercio internacional regional. La salud a través de sus autoridades regulatorias debe ser parte del dialogo comercial internacional.The National Academy of Medicine is an essential space to discuss regulatory science in health, and to position its impact on health and economy. Framed within the stewardship role of the health authority, health regulation is the action of protecting the population against involuntary health hazards against which the individual cannot protect him/herself. It is an essential function of public health, an institutional component of the health system and, therefore, linked to its reforms and to universal coverage. Regulation has its support on an epidemiological, organizational, legal, sociological and economic theoretical body. It has a methodological body that supports its regulatory process based on risk analysis and that is translated into regulations, implementations, compliance, monitoring and evaluation of the regulation. It has a professional, financial, organizational, legal and governance architecture. Given its universal action, it has a widespread impact on the population and a substantial economic effect, influencing on at least 17% of regional international trade. Health through its regulatory authorities should be an early part of international trade discussions.

Sobrepeso y obesidad en niños y adolescentes en México, actualización de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016 / Overweight and obesity in children and adolescents, 2016 Halfway National Health and Nutrition Survey update

Resumen: 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.

Abstract: Objective: To estimate recent overweight and obesity prevalences in Mexican population under 20 years from Halfway National Health and Nutrition Survey (Ensanut MC 2016). Materials and methods: Ensanut MC 2016 is a probabilistic national survey which gives representative information from national, regional and rural/urban levels. BMIz was estimated through weight and height, then it was classified into overweight risk or overweight or obesity according to WHO growth reference standards. Association between overweight and sociodemographic information was analyzed through logistic regression models. Results: Overweight-obesity prevalence was 5.1% in girls and 6.5% in boys<5y, 32.8% in girls and 33.7% in boys 5-11y, and 39.2% in female adolescents and 33.5% in male adolescents. Female adolescents from rural localities increased overweight-obesity prevalence from 27.7% in 2012 to 37.2% in 2016. Conclusions: Overweight-obesity increased in girls and females, mainly from rural areas. Strategies focused in containing this phenomenon are encouraged to implement in this context.

[Overweight and obesity in children and adolescents, 2016 Halfway National Health and Nutrition Survey update]. / Sobrepeso y obesidad en niños y adolescentes en México,actualización de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016.

OBJECTIVE: To estimate recent overweight and obesity prevalences in Mexican population under 20 years from Halfway National Health and Nutrition Survey (Ensanut MC 2016). MATERIALS AND METHODS: Ensanut MC 2016 is a probabilistic national survey which gives representative information from national, regional and rural/urban levels. BMIz was estimated through weight and height, then it was classified into overweight risk or overweight or obesity ac¬cording to WHO growth reference standards. Association between overweight and sociodemographic information was analyzed through logistic regression models. RESULTS: Overweight-obesity prevalence was 5.1% in girls and 6.5% in boys<5y, 32.8% in girls and 33.7% in boys 5-11y, and 39.2% in female adolescents and 33.5% in male adolescents. Female adolescents from rural localities increased overweight-obesity prevalence from 27.7% in 2012 to 37.2% in 2016. CONCLUSIONS: Overweight-obesity increased in girls and females, mainly from rural areas. Strategies focued in containing this phenomenon are encouraged to implement in this context.

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.

[Methodological design of the National Health and Nutrition Survey 2016]. / Diseño metodológico de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016.

OBJECTIVE:: Describe the design methodology of the halfway health and nutrition national survey (Ensanut-MC) 2016. MATERIALS AND METHODS: The Ensanut-MC is a national probabilistic survey whose objective population are the inhabitants of private households in Mexico. The sample size was determined to make inferences on the urban and rural areas in four regions. Describes main design elements: target population, topics of study, sampling procedure, measurement procedure and logistics organization. RESULTS: A final sample of 9 479 completed household interviews, and a sample of 16 591 individual interviews. The response rate for households was 77.9%, and the response rate for individuals was 91.9%. CONCLUSIONS: The Ensanut-MC probabilistic design allows valid statistical inferences about interest parameters for Mexico´s public health and nutrition, specifically on overweight, obesity and diabetes mellitus. Updated information also supports the monitoring, updating and formulation of new policies and priority programs.

Diseño metodológico de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016 / Methodological design of the National Health and Nutrition Survey 2016

Resumen: Objetivo: Describir el diseño metodológico de la Encuesta Nacional de Salud y Nutrición de Medio Camino (Ensanut-MC) 2016. Material y métodos: La Ensanut-MC es una encuesta probabilística nacional cuya población objetivo son los habitantes de viviendas particulares en México. El tamaño de muestra se determinó para poder hacer inferencias sobre las localidades urbanas y rurales de cuatro regiones. Se describen los elementos principales del diseño: población objetivo, temas de estudio, procedimiento de muestreo, procedimiento de medición y organización logística. Resultados: Se obtuvieron 9 479 entrevistas de hogar completas y 16 591 entrevistas de individuos completos. La tasa de respuesta de hogar fue 77.9%. La tasa de respuesta de individuo fue 91.9%. Conclusiones: El diseño probabilístico de la Ensanut-MC permite hacer inferencias estadísticas válidas sobre parámetros de interés para la salud y nutrición pública de México, específicamente en variables de sobrepeso, obesidad y diabetes mellitus. Asimismo, la información actualizada sustentará el monitoreo, la actualización y formulación de nuevas políticas y programas prioritarios.

Abstract: Objective: Describe the design methodology of the halfway health and nutrition national survey (Ensanut-MC) 2016. Materials and methods The Ensanut-MC is a national probabilistic survey whose objective population are the inhabitants of private households in Mexico. The sample size was determined to make inferences on the urban and rural areas in four regions. Describes main design elements: target population, topics of study, sampling procedure, measurement procedure and logistics organization. Results A final sample of 9 479 completed household interviews, and a sample of 16 591 individual interviews. The response rate for households was 77.9%, and the response rate for individuals was 91.9%. Conclusions The Ensanut-MC probabilistic design allows valid statistical inferences about interest parameters for Mexico´s public health and nutrition, specifically on overweight, obesity and diabetes mellitus. Updated information also supports the monitoring, updating and formulation of new policies and priority programs.

Changes in Prices After an Excise Tax to Sweetened Sugar Beverages Was Implemented in Mexico: Evidence from Urban Areas.

In 2014 an excise tax to non-alcoholic sweetened beverages (SSB) was implemented in Mexico. The objective of this paper is to study whether and to what degree these taxes passed-through onto SSB prices in urban areas overall and by region, type of beverage and package size. Prices were obtained from the National Institute of Statistics and Geography from 2011 to 2014. We applied a pre-post quasi-experimental approach using fixed effects models. In sensitivity analysis we applied other model specifications to test the robustness of the findings and we also present weighted estimations based on household purchases. The dependent variables are real prices of a specific beverage category; the main independent variables are dummies for each month of 2014, and the models adjust for time trends and seasonality. Results suggest that the SSB tax passed along to consumers for all SSBs and we found overshifting for the carbonated SSBs. A greater effect is seen among the small package sizes, and we see heterogeneous effects by region. Estimating the effect of the tax on prices is important to understand the potential effect on consumption.

[National Health and Nutrition Survey 2012: design and coverage]. / Encuesta Nacional de Salud y Nutrición 2012: diseño y cobertura.

OBJECTIVE: To describe the design and population coverage of the National Health and Nutrition Survey 2012 (NHNS 2012). MATERIALS AND METHODS: The design of the NHNS 2012 is reported, as a probabilistic population based survey with a multi-stage and stratified sampling, as well as the sample inferential properties, the logistical procedures, and the obtained coverage. RESULTS: Household response rate for the NHNS 2012 was 87%, completing data from 50,528 households, where 96 031 individual interviews selected by age and 14,104 of ambulatory health services users were also obtained. CONCLUSION: The probabilistic design of the NHNS 2012 as well as its coverage allowed to generate inferences about health and nutrition conditions, health programs coverage, and access to health services. Because of their complex designs, all estimations from the NHNS 2012 must use the survey design: weights, primary sampling units, and stratus variables.

[Infant feeding practices and deterioration of breastfeeding in Mexico]. / Prácticas de alimentación infantil y deterioro de la lactancia materna en México.

OBJECTIVE: To present data on infant and young child feeding practices (IYCFP) in Mexico from the 2012 National Health and Nutrition Survey (ENSANUT 2012) to support the development of public policy. POPULATION: Women 12-49y and children <2y. Indicators of IYCFP suggested by WHO were analyzed by geographic, socioeconomic, participation in food programs and health insurance variables. RESULTS: Median duration of breast-feeding: 10.2mo and 14.4% with exclusive breastfeeding (EBF) <6m. Breastfeeding deteriorated in most vulnerable groups. Decline in EBF<6m 2006-2012 was explained by increases in consumption of formula and other milks (4%) and water (4%). Three-quarters (74%) of 6-11mo infants had minimum food diversity, and it was lower in the most vulnerable. CONCLUSIONS: Complementary feeding improved but breastfeeding declined in Mexico. Promotion actions must be integral, coordinated, financed and evaluated, with Federal government leadership and should include the participation of various stakeholders.