Fatores associados à obesidade em adolescentes

INTRODUCTION: Obesity during adolescence is considered a strong predictor of adult obesity. The present study assessed the overweight/obesity prevalence and associated factors in middle class adolescents of a school in the city of Niteroi, Rio de Janeiro, Brazil, and evaluated the correlation between body mass index with anthropometric measures of fatness. METHOD: The analysis covered 391 students aged from 15 to 17 years. Adolescents had their weight, height, skinfold thickness and upper arm circumference measured at school. A food frequency questionnaire (list of 79 items) and a questionnaire including food habits, parents anthropometric characteristics, physical activity and other factors associated with obesity were filled out by the adolescents at school. RESULTS: The proportion of overweight individuals among boys (Body Mass Index (BMI) greater than the 90th percentile of the Brazilian population) was 23.9%, whereas the prevalence among girls was 7.2%. The fact of being on a slimming diet was a relevant factor for the prediction of BMI and was 7 times more frequent among girls than among boys. Among boys, being on a diet, absence of breakfast, and family body appearance were positively associated with BMI. Among girls these variables were also significantly associated, whereas age at menarche was negatively associated with BMI. Hours of watching TV/video/ video-game was associated with BMI only among boys. The correlation coefficient between BMI and measures of fatness varied from 0.7 to 0.9 for boys, and from 0.8 to 0.90 for girls. CONCLUSIONS: BMI appears to be a good indicator of obesity among adolescents and showed that girls demonstrated an exaggerated preoccupation with body image and stereotyped slim body patterns.INTRODUÇÃO: A obesidade na adolescência é um fator preditivo da obesidade no adulto. Assim, foram avaliados os fatores associados à obesidade e o uso do índice de massa morporal (IMC). MÉTODO: Foram avaliados 391 estudantes aferindo-se: consumo de alimentos, hábitos alimentares, características antropométricas dos pais e atividade física. O IMC foi a variável dependente utilizada na regressão linear multivariada. RESULTADOS: A prevalência de sobrepeso foi 23,9% para meninos e 7,2% para meninas. Fazer dieta para emagrecer foi 7 vezes mais freqüente entre meninas do que entre meninos com sobrepeso. Nos meninos, idade, uso de dieta, omissão de desjejum, horas de televisão/"vídeo-game" e obesidade familiar apresentaram associação positiva e significante com IMC. Nas meninas, associaram-se positivamente: uso de dieta, omissão de desjejum e obesidade familiar e negativamente idade da menarca. A correlação do IMC com medidas antropométricas foi maior que 0,7. CONCLUSÕES: Um padrão estético de magreza parece predominar entre meninas e elas o atingem com hábitos e consumo alimentar inadequados

Estado nutricional e consumo de energia e nutrientes de préescolares que frequentam creches no município de Manaus, Amazonas: Existem diferenças entre creches públicas e privadas?

Objectives: To assess the nutritional status and dietary intakes of children attending public and private day care centers in Manaus, Brazil. Methods: The study assessed children aged 24 to 72 months, enrolled at two public (n=217) and two private (n=91) day care centers in Manaus. Nutritional status was classified according to Z scores for weight-for-age, weightfor- height, height-for-age and BMI-for-age. Dietary intakes were measured using the direct food-weighing method for 1 day. A 1-day dietary recall was administered to parents to assess dietary intakes outside the day care centers. The frequencies of children with nutrient intakes above and below the Estimated Average Requirements (EAR) or Adequate Intake (AI) cutoffs were calculated. Results: There proportion of overweight children was higher at the private day care centers, according to both weight-for-height and BMI-for-age indexes. Children from the public day care centers had higher intakes of polyunsaturated fat, trans fat, omega-6, vitamin C and sodium, and lower zinc intake when compared to those at private centers. Elevated energy intake and a high proportion of children with vitamin A, vitamin C, zinc and sodium intakes over the Tolerable Upper Intake Levels were observed at both types of day care center. There was a higher proportion of children with inadequate calcium intake at the public centers (27.6 vs. 7.9%, p<0.001). Conclusion: Energy and sodium intakes were above recommended levels at both types of day care center. Calcium intakes were below recommended, especially at the public day care centers. Children's diets should be monitored more closely to prevent diseases later in life

Erratum to: The study of cardiovascular risk in adolescents – ERICA: rationale, design and sample characteristics of a national survey examining cardiovascular risk factor profile in Brazilian adolescents

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Fatores associados à obesidade em adolescentes

INTRODUÇÃO: A obesidade na adolescência é um fator preditivo da obesidade no adulto. Assim, foram avaliados os fatores associados à obesidade e o uso do índice de massa morporal (IMC). MÉTODO: Foram avaliados 391 estudantes aferindo-se: consumo de alimentos, hábitos alimentares, características antropométricas dos pais e atividade física. O IMC foi a variável dependente utilizada na regressão linear multivariada. RESULTADOS: A prevalência de sobrepeso foi 23,9% para meninos e 7,2% para meninas. Fazer dieta para emagrecer foi 7 vezes mais freqüente entre meninas do que entre meninos com sobrepeso. Nos meninos, idade, uso de dieta, omissão de desjejum, horas de televisão/"vídeo-game" e obesidade familiar apresentaram associação positiva e significante com IMC. Nas meninas, associaram-se positivamente: uso de dieta, omissão de desjejum e obesidade familiar e negativamente idade da menarca. A correlação do IMC com medidas antropométricas foi maior que 0,7. CONCLUSÕES: Um padrão estético de magreza parece predominar entre meninas e elas o atingem com hábitos e consumo alimentar inadequados

Fatores associados à obesidade em adolescentes Factors associated with obesity among adolescents

INTRODUÇÃO: A obesidade na adolescência é um fator preditivo da obesidade no adulto. Assim, foram avaliados os fatores associados à obesidade e o uso do índice de massa morporal (IMC). MÉTODO: Foram avaliados 391 estudantes aferindo-se: consumo de alimentos, hábitos alimentares, características antropométricas dos pais e atividade física. O IMC foi a variável dependente utilizada na regressão linear multivariada. RESULTADOS: A prevalência de sobrepeso foi 23,9% para meninos e 7,2% para meninas. Fazer dieta para emagrecer foi 7 vezes mais freqüente entre meninas do que entre meninos com sobrepeso. Nos meninos, idade, uso de dieta, omissão de desjejum, horas de televisão/"vídeo-game" e obesidade familiar apresentaram associação positiva e significante com IMC. Nas meninas, associaram-se positivamente: uso de dieta, omissão de desjejum e obesidade familiar e negativamente idade da menarca. A correlação do IMC com medidas antropométricas foi maior que 0,7. CONCLUSÕES: Um padrão estético de magreza parece predominar entre meninas e elas o atingem com hábitos e consumo alimentar inadequados.INTRODUCTION: Obesity during adolescence is considered a strong predictor of adult obesity. The present study assessed the overweight/obesity prevalence and associated factors in middle class adolescents of a school in the city of Niteroi, Rio de Janeiro, Brazil, and evaluated the correlation between body mass index with anthropometric measures of fatness. METHOD: The analysis covered 391 students aged from 15 to 17 years. Adolescents had their weight, height, skinfold thickness and upper arm circumference measured at school. A food frequency questionnaire (list of 79 items) and a questionnaire including food habits, parents anthropometric characteristics, physical activity and other factors associated with obesity were filled out by the adolescents at school. RESULTS: The proportion of overweight individuals among boys (Body Mass Index (BMI) greater than the 90th percentile of the Brazilian population) was 23.9%, whereas the prevalence among girls was 7.2%. The fact of being on a slimming diet was a relevant factor for the prediction of BMI and was 7 times more frequent among girls than among boys. Among boys, being on a diet, absence of breakfast, and family body appearance were positively associated with BMI. Among girls these variables were also significantly associated, whereas age at menarche was negatively associated with BMI. Hours of watching TV/video/ video-game was associated with BMI only among boys. The correlation coefficient between BMI and measures of fatness varied from 0.7 to 0.9 for boys, and from 0.8 to 0.90 for girls. CONCLUSIONS: BMI appears to be a good indicator of obesity among adolescents and showed that girls demonstrated an exaggerated preoccupation with body image and stereotyped slim body patterns

A comparison of distribution curves of body mass index from Brazil and the United States for assessing overweight and obesity in Brazilian adolescents Comparación de las curvas de distribución del índice de masa corporal en Brasil y Estados Unidos para evaluar el sobrepeso y la obesidad en adolescentes brasileños

Objective. To assess the validity of recommendations for use of the 85th and 95th percentiles of body mass index (BMI) of the population in the United States of America as a screening tool to assess overweight/obesity in adolescents. Methods. We investigated the relation between BMI and percent body fat in 1 540 adolescents (717 males and 823 females) aged 10 to 17.9 years old from a private high school in Niterói, a city in the state of Rio de Janeiro, Brazil. We used bioelectric impedance, with the appropriate equations for adolescents, to estimate percent body fat, which served as the gold standard (30% for girls and 25% for boys) to calculate the sensitivity and specificity of the 85th and 95th percentiles of the United States and Brazilian distribution curves of BMI. Results. Sensitivity and specificity were high (above 80%) for the Niterói boys, except for the 85th percentile of the Brazilian curve (specificity = 61.8%) and for the 95th percentile of the United States curve (sensitivity = 55.4%). For the Niterói girls, the 85th- and 95th-percentile BMI cutoff points, from both the United States and Brazilian curves, showed low sensitivity, and that sensitivity decreased with age. Specificity was high for the girls, and much higher than it was for the boys. Conclusions. These data suggest that using BMI to screen for overweight/obesity in adolescents can generate a high percentage of false-positives for Niterói boys and an even higher percentage of false-negatives for Niterói girls. A more universal approach to using anthropometric measures to screen for overweight/obesity should be developed, preferably linked to stages of maturation.<br>Objetivos. Investigar la validez del empleo de los percentiles 85 y 95 del índice de masa corporal (IMC) de la población de los Estados Unidos de América (EE. UU.) para detectar el sobrepeso y la obesidad en adolescentes. Métodos. Se investigó la relación entre el IMC y el porcentaje de grasa corporal en 1 540 adolescentes (717 del sexo masculino y 823 del sexo femenino) de 10 a 17,9 años de una escuela secundaria privada de Niterói, una ciudad del estado de Rio de Janeiro, Brasil. Como referencia para calcular la sensibilidad y especificidad de los percentiles 85 y 95 de las curvas de distribución del IMC en los EE. UU. y Brasil se utilizó el porcentaje de grasa corporal, determinado mediante impedancia bioeléctrica, con ecuaciones ajustadas para los adolescentes. Se consideró como obesidad un porcentaje de grasa corporal del 30% en el sexo femenino y del 25% en el sexo masculino. Resultados. La sensibilidad y la especificidad fueron elevadas (> 80%) para los adolescentes del sexo masculino de Niterói, exceptuando el percentil 85 de la curva de Brasil (especificidad del 61,8%) y el percentil 95 de la curva de EE. UU. (sensibilidad del 55,4%). Para las adolescentes del sexo femenino, los percentiles 85 y 95 de las curvas de ambos países presentaron una baja sensibilidad, que disminuía con la edad; la especificidad, en cambio, fue elevada, y mucho mayor que en el sexo masculino. Conclusiones. Estos datos indican que el uso del IMC para identificar el sobrepeso y la obesidad en adolescentes de Niterói puede generar un alto porcentaje de resultados positivos falsos en los del sexo masculino y un porcentaje todavía mayor de resultados negativos falsos en las del sexo femenino. Para detectar el sobrepeso y la obesidad sería necesario un método más universal que las medidas antropométricas, de preferencia relacionado con los estadios de maduración

Readiness for behavioral change and variation in food consumption among adolescents from a school-based community trial in Duque de Caxias, RJ

OBJECTIVE: To investigate the influence of the stage of readiness for changes in food consumption variation among adolescents participating in school-based community trial in Duque de Caxias (RJ), Brazil. METHODS: It is a secondary analysis of a one-year randomized community trial to prevent excessive weight gain in students attending the 5th grade in 20 public schools in the municipality of Duque de Caxias. The activities conducted discouraged the consumption of sweetened beverages and cookies and encouraged the consumption of fruits and beans. A food frequency questionnaire was applied at the beginning and at the end of the study. The stages of readiness for behavioral change vary in a scale from (1) "I don't think of changing diet" to (5) "I'm already changing my diet successfully". For the longitudinal analyses, we used generalized linear mixed models. RESULTS: There was a greater change in the consumption of fruit and soft drinks among participants in the intervention group who were in the action stage, compared to participants who did not think about changing their diet. CONCLUSION: The proposed strategy may be used to identify population groups with motivation for changes in dietary behavior