Glycemic index, glycemic load, and metabolic syndrome in Mexican adolescents: a cross-sectional study from the NHNS-2012.

BACKGROUND: The role of dietary glycemic index (GI) and dietary glycemic load (GL) on metabolic syndrome (MetS) in youth populations remains unclear. The aim of the present study was to evaluate the association among dietary GI, dietary GL, and MetS and its components in Mexican adolescents. METHODS: This study was conducted within the framework of the National Health and Nutrition Survey 2012, a cross-sectional, probabilistic, population-based survey with a multistage stratified cluster sampling design. We analyzed a sample of 1346 subjects aged 12-19 years, representing 13,164,077 adolescents. Dietary habits were assessed through a validated semiquantitative food-frequency questionnaire. We assigned GI values using the International Tables of GI values. We defined MetS according to the International Diabetes Federation criteria developed for adolescents. Multiple logistic regression models were used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) to evaluate the association between categories of dietary GI and GL and the prevalence of MetS and its components. RESULTS: We observed no associations between dietary GI or GL and MetS prevalence. Female adolescents in the highest category of dietary GI had higher odds of abnormal blood pressure (OR = 3.66; 95% CI, 1.46-9.22; P for trend = 0.012). A high dietary GL was also associated with higher odds of abnormal blood pressure in female adolescents (OR = 5.67; 95% CI, 1.84-17.46; P for trend = 0.003). CONCLUSIONS: We found higher odds of abnormal blood pressure for female adolescents with a high dietary GI and dietary GL.

Methodology for estimating dietary data from the semi-quantitative food frequency questionnaire of the Mexican National Health and Nutrition Survey 2012 / Metodología para la estimación de información dietética del cuestionario semicuantitativo de frecuencia de consumo de alimentos de la Encuesta Nacional de Salud y Nutrición 2012

Abstract: Objective: To describe the methodology used to clean up and estimate dietary intake (DI) data from the Semi-Quantitative Food Frequency Questionnaire (SFFQ) of the Mexican National Health and Nutrition Survey 2012. Materials and methods: DI was collected through a shortterm SFFQ regarding 140 foods (from October 2011 to May 2012). Energy and nutrient intake was calculated according to a nutrient database constructed specifically for the SFFQ. Results: A total of 133 nutrients including energy and fiber were generated from SFFQ data. Between 4.8 and 9.6% of the survey sample was excluded as a result of the cleaning process.Valid DI data were obtained regarding energy and nutrients consumed by 1 212 pre-school children, 1 323 school children, 1 961 adolescents, 2 027 adults and 526 older adults. Conclusions: We documented the methodology used to clean up and estimate DI from the SFFQ used in national dietary assessments in Mexico.

Resumen: Objetivo: Describir la metodología para la estimación y limpieza de datos sobre ingestión dietética (ID) derivados del cuestionario semicuantitativo de frecuencias de consumo de alimentos (CFCAS) de la Encuesta Nacional de Salud y Nutrición 2012. Material y métodos: La información de ID fue recolectada a través de un CFCAS de siete días que obtuvo información sobre la ingesta de 140 alimentos (de octubre de 2011 a mayo de 2012). La ingesta de energía y nutrientes fue calculada utilizando una base de datos de nutrientes construida para el procesamiento del CFCAS. Resultados: Se obtuvieron 133 nutrimentos (incluidos energía y fibra). Entre 4.8 y 9.6% de la muestra fue excluido, con lo que se obtuvo información válida sobre la ingesta de energía y nutrimentos para 1 212 preescolares, 1 323 escolares, 1 961 adolescentes, 2 027 adultos y 526 adultos mayores. Conclusiones: Se documentó la metodología para la estimación de la ID y los criterios de limpieza para CFCAS usados para la evaluación dietética nacional.

Methodology for estimating dietary data from the semi-quantitative food frequency questionnaire of the Mexican National Health and Nutrition Survey 2012.

OBJECTIVE:: To describe the methodology used to clean up and estimate dietary intake (DI) data from the Semi-Quantitative Food Frequency Questionnaire (SFFQ) of the Mexican National Health and Nutrition Survey 2012. MATERIALS AND METHODS:: DI was collected through a shortterm SFFQ regarding 140 foods (from October 2011 to May 2012). Energy and nutrient intake was calculated according to a nutrient database constructed specifically for the SFFQ. RESULTS:: A total of 133 nutrients including energy and fiber were generated from SFFQ data. Between 4.8 and 9.6% of the survey sample was excluded as a result of the cleaning process.Valid DI data were obtained regarding energy and nutrients consumed by 1 212 pre-school children, 1 323 school children, 1 961 adolescents, 2 027 adults and 526 older adults. CONCLUSIONS:: We documented the methodology used to clean up and estimate DI from the SFFQ used in national dietary assessments in Mexico.