Obesity in adolescence and its main determinants

O objetivo deste trabalho foi discutir os principais fatores ambientais determinantes do sobrepeso e da obesidade em adolescentes, fundamentando-se em uma revisão crítica sobre o assunto. Para a revisão do tema foram consultadas as principais bases de dados nacionais e internacionais, entre elas, Medline/Pubmed, Web of Science, SciELO, Lilacs, compreendendo o período de 1975 a 2009. Os descritores e termos MeSH utilizados na busca foram: "sobrepeso", "obesidade", "adolescência", "adolescentes", "atividade física", "ingestão alimentar". Os resultados das pesquisas indicam que as mudanças ocorridas nos padrões alimentares nas últimas décadas, como o aumento do consumo de açúcares simples, alimentos industrializados e ingestão insuficiente de frutas e hortaliças, estão diretamente associadas ao ganho de peso dos adolescentes. Além disso, a redução progressiva da prática de atividade física combinada ao maior tempo dedicado às atividades de baixa intensidade, como assistir televisão, usar computador e jogar videogame, também tem contribuído para o aumento de peso dos jovens. Conclui-se, portanto, que as variáveis relacionadas ao padrão alimentar e de atividade física devem ser priorizadas nas intervenções voltadas para a prevenção da obesidade entre adolescentes.The objective of this paper was to discuss the main environmental factors determining overweight and obesity in adolescents, based on a critical review of the subject. The main national and international health databases, Medline/PubMed, Web of Science, SciELO, and Lilacs were searched including publications from 1975 to 2009. The following key-words and respective MeSH terms were used: "overweight", "obesity", "adolescence", "adolescents", "physical activity", "food intake". The findings showed that changes in dietary patterns in recent decades as the increased consumption of simple sugars, processed foods, and inadequate intake of fruits and vegetables have contributed directly to the weight gain in this population. In addition, the progressive reduction in physical activity associated with increased time spent with low-intensity activities like television viewing, playing computer and video games has contributed to the weight gain of adolescents. In conclusion, variables related to dietary pattern and physical activity should be prioritized interventions directed toward the prevention of obesity among adolescents

Energy and nutrients disposal in residences: the contrast between north and south regions of Brazil

Com o objetivo de analisar a disponibilidade domiciliar de energia, a participação relativa dos macronutrientes no Valor Energético Total (VET) e a contribuição dos diferentes grupos de alimentos na energia disponível nos domicílios das regiões Norte e Sul do país, segundo o rendimento mensal familiar, foi proposto o presente estudo. Utilizou-se para a elaboração das análises os microdados da Pesquisa de Orçamentos Familiares - 2002/2003 realizada pelo Instituto Brasileiro de Geografia e Estatística (IBGE). Para as análises nutricionais, utilizou-se o software Virtual Nutri. O teste de regressão linear múltipla foi aplicado para analisar o efeito dos rendimentos sobre a disponibilidade de energia e nutrientes. Verificou-se uma relação inversa entre a participação dos carboidratos no VET e a renda. A contribuição dos lipídios para o VET apresentou tendência de crescimento, de acordo com o aumento da renda. Quanto à participação dos distintos grupos de alimentos no VET, destaca-se a reduzida contribuição energética das frutas, verduras e legumes para praticamente a totalidade dos grupamentos familiares. Foram identificadas indesejáveis contribuições (consideradas excessivas) dos doces, açúcares e refrigerantes para o VET disponível para as famílias de ambas as regiões estudadas.This study was proposed to analyze the domiciliary energy disposal, the relative participation of macronutrients in the Total Energy Value (VET) and the contribution of different food groups in the disposal energy in residences of the North and South regions of Brazil according to the monthly family income. It was used the micro data of the Family Budget Research - POF related to the period of 2002/2003 which was carried out by the Brazilian Institute of Geography and Statistics - IBGE. The nutritional analyses were made by using the Virtual Nutri software. The multiple linear regression test was used to capture the income effect over energy and nutrients disposal. There is a reciprocal and inverse relation between the carbohydrates participation in the VET and the family income. The participation of lipids to the VET presented a growth tendency, according to the income increase. Regarding the participation of various food groups in the VET, the energetic contribution of fruits, greens and vegetables was outstandingly reduced to the almost entire family groupings. It was identified the undesirable contribution of sweets, simpler carbohydrates and soft drinks, which was considered excessive to the disposable VET

Validation of a Food Frequency Questionnaire by food groups for the adolescent population

OBJETIVO: Verificar a validade do Questionário de Freqüência Alimentar para Adolescentes para avaliar o consumo de grupos de alimentos entre escolares de Piracicaba, São Paulo. MÉTODOS: Participaram do estudo 94 adolescentes, com idade entre 11 e 15 anos, matriculados em uma escola da rede pública. O consumo alimentar foi avaliado pelo Questionário de Freqüência Alimentar para Adolescentes (QFAA) e a média de dois Recordatórios de 24 horas (R24h) foi utilizada como método de referência. Os itens alimentares foram classificados em 18 grupos. Foram realizadas análises descritivas, teste t-Student pareado e de Wilcoxon, coeficientes de correlação de Pearson e de Spearman. Foram também utilizadas análise de quartis e estatística Kappa ponderado. Os coeficientes de correlação foram corrigidos pela variância intrapessoal dos R24h, estimada a partir de ANOVA com um fator de classificação. RESULTADOS: Não foram verificadas diferenças significativas entre os instrumentos para o arroz, massas, carnes, refrigerantes e sucos artificiais. Os coeficientes de correlação corrigidos pela variabilidade intrapessoal variaram de -0,26 a 0,78. A concordância de classificação dos indivíduos no mesmo quartil de consumo para ambos os métodos variou de 22% (massas) a 50% (feijão). Para quartis opostos, os grupos que tiveram mais de 10% dos indivíduos classificados incorretamente foram massas (19%), carnes (13%) e gorduras (11%). Os valores de Kappa ponderado variaram de - 0,15 (massas) a 0,56 (feijão). O QFAA superestimou o consumo de quase a totalidade dos grupos alimentares e subestimou os grupos dos óleos, feijão, carnes e refrigerantes. CONCLUSÃO: O instrumento apresentou boa validade para feijão, verduras e legumes, leite e derivados, biscoitos recheados e para o arroz.OBJECTIVE: To verify the validity of the Food Frequency Questionnaire for Adolescents in order to evaluate food group consumption among adolescents from Piracicaba, São Paulo. METHODS: The study was carried out with 94 adolescents, ranging from 11 to 15 years of age, from the public education system. Food consumption was assessed by the Food Frequency Questionnaire for Adolescents (QFAA) and the average of two 24-hour recalls (R24h) was used as a reference method. The food items were classified into 18 groups. Descriptive analyses, paired t-test and Wilcoxon test, Pearson and Spearman coefficients were performed. Analysis of quartiles and Kappa test were used. Correlation coefficients were adjusted by the within-subject variance of the 24-hour recalls, from one-way ANOVA. RESULTS: No significant differences were found between the tools for rice, pasta, meat, soft drinks, and artificial juices. The correlation coefficients adjusted by within-subject variability ranged from -0.26 to 0.78. Agreement of individuals' classification in quartiles of food consumption for both methods ranged from 22% (pasta) to 50% (beans). For discordant quartiles, the groups that presented more than 10% of misclassified subjects were pasta (19%), meat (13%) and fats (11%). The values of the Kappa test ranged from -0.15 (pastas) to 0.56 (beans). The food frequency questionnaire over-estimated the consumption of almost all the food groups and under-estimated the groups of oils, beans, meats, and soft drinks CONCLUSION: The food frequency questionnaire revealed good validity for beans, vegetables, milk and dairy, cookies with filling, and rice.FAPES

Influence of food intake and physical activity patterns on the nutritional status of adolescents from Piedade, São Paulo, Brazil

OBJETIVO: Identificar os fatores dietéticos e de atividade física associados ao estado nutricional de adolescentes escolares. MÉTODOS: Estudo transversal com 105 adolescentes de ambos os sexos, idade de 10 a 14 anos, matriculados em escolas públicas de Piedade (SP). Foram coletadas informações sobre consumo alimentar (recordatório 24 horas), padrão de atividade física (atividades físicas e sedentárias) e estado nutricional avaliado pelo índice de massa corporal. Consideraram-se insuficientemente ativos os adolescentes que praticavam menos de 300 minutos/semana de atividade física. Foram classificados como sedentários aqueles que dedicavam período de tempo igual ou superior a duas horas por dia a atividades passivas. Para identificar os fatores associados ao estado nutricional, recorreu-se à regressão linear múltipla. RESULTADOS: A prevalência de excesso de peso foi maior entre os meninos (17,9 versus 13,6%, p<0,05). Dos adolescentes, 18% foram considerados insuficientemente ativos. Não houve associação entre as variáveis dietéticas e o estado nutricional. Observou-se diferença significativa apenas para o tempo dedicado para jogar videogame (p=0,005), que foi maior nos adolescentes eutróficos. Sete em cada dez adolescentes dedicavam mais de duas horas diárias às atividades sedentárias, como assistir à televisão, usar o computador e jogar videogame. Na análise múltipla, somente a idade se associou positivamente ao IMC (p=0,001). CONCLUSÕES: Há necessidade de novas investigações de caráter prospectivo que estabeleçam relações mais claras entre os fatores relacionados ao estilo de vida e o índice de massa corporal em adolescentes.OBJECTIVE: To identify dietary and physical activity factors associated to the nutritional status of adolescent students. METHODS: Cross-sectional study of 105 adolescents of both genders, aged 10 to 14 years, studying at public schools in Piedade, São Paulo, Brazil. Data regarding food intake (24 hour recall), physical activity patterns (physical and sedentary activities) and nutritional status measured by body mass index were collected. The adolescents were characterized as insufficiently active if physical activities were practiced for less than 300 minutes per week. They were considered sedentary if they spent two hours or more per day in passive activities. Multiple linear regression was performed to identify factors associated to the nutritional status. RESULTS: The prevalence of overweight was higher among boys (17.9 versus 13.6%, p<0.05) and 18.0% of the adolescents were considered insufficiently active. There was no association between dietary and nutritional status variables. A significant difference was observed only for the time spent playing videogames (p=0.005), that was higher among eutrophic adolescents. Seven in ten adolescents spent more than two hours a day on sedentary activities (watching television, using the computer and playing videogames). In multiple regression analysis, only age was positively associated with the BMI (p=0.001). CONCLUSIONS: Further prospective investigations are necessary to establish clearer relationships among factors related to lifestyle and body mass index among adolescents.Conselho Nacional de Desenvolvimento Científico (CNPq

A alimentação das famílias do Centro-Oeste brasileiro: subsídios para ações de segurança alimentar e nutricional

O objetivo da pesquisa foi analisar a disponibilidade domiciliar de energia, colesterol e fibras, a participação relativa dos macronutrientes no Valor Energético Total - VET e a contribuição dos grupos de alimentos na energia disponível para as famílias residentes na Região Centro-Oeste do País. Utilizou-se, para a elaboração das análises, os microdados da Pesquisa de Orçamentos Familiares – POF, realizada pelo Instituto Brasileiro de Geografia e Estatística - IBGE, no período de 2002 a 2003. Para as análises nutricionais, utilizou-se o software Virtual Nutri. Constatou-se uma relação inversa entre a participação dos carboidratos no VET e a renda. A mesma tendência foi observada para os lipídios e colesterol. A disponibilidade de fibras revelou-se muito aquém dos valores preconizados para a totalidade dos estratos de renda. Quanto à participação dos distintos grupos de alimentos no VET, destaca-se a reduzida contribuição energética das frutas e hortaliças para os moradores das áreas urbanas e rurais. A contribuição dos doces, açúcares e refrigerantes foi identificada como excessiva no VET disponível para as famílias de ambos os estratos geográficos

Validação de um questionário de frequência alimentar para avaliar o consumo de carotenóides, frutas e hortaliças: o método das tríades

The aim of this study was to validate the intake of carotenoids, fruits and vegetables estimated by the Food Frequency Questionnaire for Adolescents (FFQA) using the method of triads. Blood samples were collected from 80 elementary school adolescents to assess serum levels of &#946;-carotene. Partial correlation coefficients (r) were calculated between an estimated intake of carotenoids, fruits and vegetables and the serum levels of &#946;-carotene. Validity coefficients were calculated using the method of triads. With the exception of carotenoids, partial r from the food frequency questionnaire (FFQ) were greater than those of the 24-hour recall (24hR). The fruit/vegetable group showed the highest partial r for the FFQ (r = 0.235) and the 24hR (r = 0.137). The highest validity coefficient was obtained for the vegetable group, as assessed by the FFQ (r = 0.873). On average, the validity coefficient values for the FFQ were greater than those obtained for the 24hR or the &#946;-carotene serum levels. The FFQA is an accurate tool for estimating the intake of carotenoids, fruits and vegetables in this population group.O objetivo do estudo foi validar a ingestão de carotenóides, frutas e hortaliças estimada pelo Questionário de Frequência Alimentar para Adolescentes (QFAA) utilizando o método das tríades. Foram coletadas amostras sanguíneas de 80 adolescentes de uma escola de Ensino Fundamental para análise do b-caroteno plasmático. Coeficientes de correlação (r) parciais foram obtidos entre a ingestão de carotenóides, frutas e hortaliças e o b-caroteno plasmático. Os coeficientes de validade foram estimados a partir do método das tríades. O QFA apresentou valores de r parcial superiores ao recordatório alimentar de 24 horas (R24h), exceto para carotenóides. O grupo das frutas/hortaliças apresentou os maiores valores de r parciais tanto para o questionário de frequência alimentar (QFA) (r = 0,235) quanto para R24h (r = 0,137). O maior coeficiente de validade foi o do grupo de hortaliças avaliado pelo QFA (r = 0,873). Os valores de coeficiente de validade observados para o QFA foram em média superiores aos obtidos para R24h e b-caroteno plasmático. O QFAA é um instrumento com boa acurácia para estimar o consumo de carotenóides, frutas e hortaliças nesse grupo populacional.(FAPESP) São Paulo Research Foundatio

Estimate of corrected values and the effect of correction for measurement error in dietary data obtained by the Food Frequency Questionnaire for Adolescents (AFFQ)

The scope of this study was to estimate calibrated values for dietary data obtained by the Food Frequency Questionnaire for Adolescents (FFQA) and illustrate the effect of this approach on food consumption data. The adolescents were assessed on two occasions, with an average interval of twelve months. In 2004, 393 adolescents participated, and 289 were then reassessed in 2005. Dietary data obtained by the FFQA were calibrated using the regression coefficients estimated from the average of two 24-hour recalls (24HR) of the subsample. The calibrated values were similar to the the 24HR reference measurement in the subsample. In 2004 and 2005 a significant difference was observed between the average consumption levels of the FFQA before and after calibration for all nutrients. With the use of calibrated data the proportion of schoolchildren who had fiber intake below the recommended level increased. Therefore, it is seen that calibrated data can be used to obtain adjusted associations due to reclassification of subjects within the predetermined categories

Validade e confiabilidade das medidas referidas de peso e estatura para o diagnóstico do estado nutricional de adolescentes

PURPOSE: To assess the validity and reliability of self-reported height, weight, and Body Mass Index (BMI) to diagnose the nutritional status of adolescents. METHODS: The study included 360 public school students of both genders, with ages ranging from 10 to 15 years. Adolescents self-reported their weight and height, and these values were later obtained directly by interviewers. The validity of BMI based on self-reported measures was calculated using sensitivity and specificity indexes, and positive predictive value (PPV). Agreement between self-reported and measured BMI was evaluated using Kappa's weight coefficient, the Lin correlation coefficient, and Bland-Altman and Lin's plots. RESULTS: Both girls and boys underestimated their weight (-1.0 girls and boys) and height (girls - 1.2 and boys - 0.8) (p < 0.001). BMI presented moderate agreement between measured and self-reported values. Sensitivity of estimated BMI based on reported measures to classify obese subjects was higher for boys (87.5%) than it was for girls (60.9%), whereas specificity was higher for girls (92.7%) than it was for boys (80.6%). PPV was high only for classification of normal-weight adolescents. CONCLUSIONS: Self-reported measures of weight and height in adolescents do not present valid measures; therefore, they should not be used to replace measured values. Additionally, we observed that 10% of obese boys and 40% of obese girls could have remained unidentified if we had used only self-reported measures, emphasizing the effects of the low reliability of self-reporting. __________________________________________________________________________________________________________________ RESUMO:OBJETIVO: Avaliar a validade do peso, estatura e Índice de Massa Corporal (IMC) referidos e sua confiabilidade para o diagnóstico do estado nutricional de adolescentes de Piracicaba. MÉTODOS: Participaram do estudo 360 adolescentes de ambos os sexos, de escolas públicas de Piracicaba, com idade entre 10 e 15 anos. Os adolescentes auto-relataram seu peso e estatura, sendo esses valores obtidos por medidas diretas, logo em seguida, pelos entrevistadores. A validade do IMC referido foi calculada segundo índices de sensibilidade, especificidade e valor preditivo positivo (VPP). Avaliou-se a concordância entre as categorias de IMC obtido por meio das medidas referidas e aferidas a partir do coeficiente kappa ponderado, coeficiente de correlação de Lin. e gráficos de Bland e Altman e Lin. RESULTADOS: Verificou-se que tanto os meninos quanto as meninas subestimaram o peso (-1,0 meninas e meninos) e a estatura (meninas -1,2 e meninos -0,8) (p < 0,001). Os valores de IMC aferidos e referidos apresentaram uma concordância moderada. A sensibilidade do IMC referido para classificar os indivíduos obesos foi maior para os meninos (87,5%), enquanto a especificidade foi maior para as meninas (92,7%). O VPP foi elevado somente para a classificação da eutrofia. CONCLUSÕES: As medidas referidas de peso e estatura de adolescentes não representam medidas válidas e, portanto, não devem ser usadas em substituição aos valores mensurados. Além disso, verificou-se que 10% dos meninos obesos e 40% das meninas obesas poderiam permanecer não identificados utilizando-se as medidas auto-referidas, confirmando a baixa validade das medidas auto-referidas

Obtenção de farinha de batata-doce biofortificada / Obtaining of biofortified sweetpotato flour

Introduction: Biofortified foods such as beuregard sweetpotato flour (Ipomoea batatas) with high ?-carotene contents play a very important role incombating hypovitaminosisA, reducing malnutrition and ensuring good health. Objective: Obtain biofortified beuregard sweetpotato flour with characteristics that allow its preservation and use in formulated products such as bread, cakes, biscuits and others. Materials and Methods: Beuregard sweetpotatoes that are grown  in São Paulo and Minas Gerais were used. The tubers were  sanitized, weighed in analytical scale, peeled, chopped, bleached, dehydrated in drying ovens and grounded in dim light environment. The flour was weighed, packed and frozen. The calculation of yield, granulometry, centesimal composition (moisture, ash, protein, lipids, carbohydrates and fiber), and physical-chemical characterization (acidity, pH, Brix, water activity, color) was made according to the AOAC; AACC and IAL in triplicate, and the Total Energy Value (VET) by Atwater. Results and Discussion:  The yield of the flour grown in Minas Gerais was lower (9.66%) due to the greater amount of husks. Both flour had more than 50% of particle size &lt; 60ABNT. The results of the São Paulo and Minas Gerais flour analyzes presented, respectively, an average value of 9.76%-9.95% moisture; 3.66%-6.95% ash; 7.38%-9.85% protein; 0.76%-1.39% lipids; 78.89%-71.86% carbohydrates; 9.53%-12.28%  fiber; 351.92Kcal-339.35Kcal VET; 1.91% acidity; 5.62-5.46 pH, 8.10ºBx-9.63ºBx Brix, 0.35-0.33 of water activity and orange color. Its major components are carbohydrates and fibers that, are source of energy. The differences found in the contents of its components can be due to the geographical conditions where they were cultivated. The moisture and acidity are within the maximum allowed value and the physico-chemical characteristics  are ideal for its conservation. Conclusion: The analyzes performed presented patterns of identity and quality that are in agreement with the literature  can be used in combination with other flour for the elaboration of products formulated with a higher content of pro-vitamin A carotenoids

Perfis de DPOC e características tratáveis utilizando recursos mínimos: Identificação, árvore de decisão e estabilidade longitudinal

Background: Chronic obstructive pulmonary disease (COPD) is highly heterogeneous and complex. Hence, personalising assessments and treatments to this population across different settings and available resources imposes challenges and debate. Research efforts have been made to identify clinical phenotypes or profiles for prognostic and therapeutic purposes. Nevertheless, such profiles often do not describe treatable traits, focus on complex physiological/pulmonary measures which are frequently not available across settings, lack validation and/or their stability over time is unknown. Objective: To identify profiles and their treatable traits based on simple and meaningful measures; to develop and validate a profile decision tree; and to explore profiles’ stability over time in people with COPD. Methods: An observational, prospective study was conducted with people with COPD. Clinical characteristics, lung function, symptoms, impact of the disease (COPD assessment test–CAT), health-related quality of life, physical activity, lower-limb muscle strength and functional status were collected cross-sectionally and a subsample was followed-up monthly over six months. A principal component analysis and a clustering procedure with k-medoids were applied to identify profiles. Pulmonary and extrapulmonary (i.e., physical, symptoms and health status, and behavioural/life-style risk factors) treatable traits were identified in each profile based on the established cut-offs for each measure available in the literature. The decision tree was developed with 70% and validated with 30% of the sample, cross-sectionally. Agreement between the profile predicted by the decision tree and the profile defined by the clustering procedure was determined using Cohen’s Kappa. Stability was explored over time with a stability score defined as the percentage ratio between the number of timepoints that a participant was classified in the same profile (most frequent profile for that participant) and the total number of timepoints (i.e., 6). Results: 352 people with COPD (67.4±9.9 years; 78.1% male; FEV1=56.2±20.6% predicted) participated and 90 (67.6±8.9 years; 85.6% male; FEV1=52.1±19.9% predicted) were followed-up. Four profiles were identified with distinct treatable traits. The decision tree was composed by the CAT, age and FEV1% predicted and had an agreement of 71.7% (Cohen’s Kappa=0.62, p<0.001) with the actual profiles. 48.9% of participants remained in the same profile whilst 51.1% moved between two (47.8%) and three (3.3%) profiles over time. The overall stability of profiles was 86.8±15%. Conclusion: Profiles and treatable traits can be identified in people with COPD with simple and meaningful measures possibly available even in minimal-resource settings. Regular assessments are recommended as people with COPD may change profile over time and hence their needs of personalised treatment.N/