Resumo:
Este estudo avaliou a associação entre o grau de processamento de alimentos e o teor de nutrientes da dieta e testou o efeito do grau de processamento sobre a pressão arterial em adolescentes e adultos de Porto Alegre. O teste de hipóteses foi feito em um estudo transversal, com amostra probabilística de Porto Alegre, onde foram recrutados 599 adolescentes e 1685 adultos, participantes do estudo SOFT (Estudo da síndrome de obesidade e fatores de risco cardiovasculares). Em uma sub amostra de adolescentes e adultos, recrutada com a finalidade de validar o questionário de frequência de consumo alimentar (QFA), a dieta foi avaliada em dois recordatórios de 24 horas (RA24h), realizados consecutivamente. Informações dos RA24h foram utilizadas para desmembrar receitas e estimar a ingestão de ingredientes culinários. Alimentos foram agregados em três grupos: não processados, moderadamente processados e ultra-processados. Adolescentes e adultos do estudo SOFT foram avaliados com o mesmo QFA, com 135 itens. Peso e altura foram obtidos com equipamentos calibrados, de forma padronizada, por assistentes de pesquisa certificados. Medidas de pressão arterial foram realizadas durante a entrevista, utilizando monitor oscilométrico (OMRON CP 750) e a média de quatro aferições foi empregada na análise. Informações sobre sexo, idade, escolaridade, atividade física, tabagismo, consumo de bebidas alcoólicas foram obtidas com questionario padronizado. Todos os participantes assinaram o termo de consentimento livre e esclarecido. Análise estatística foi baseada em modelos lineares generalizados.
No estudo SOFT incluíram-se 599 adolescentes e 1685 indivíduos adultos e na sub amostra 125 e 111, respectivamente. Observou-se que o maior processamento de alimentos associou-se com a depleção de fibras e nutrientes e com consumo aumentado de sódio. Entre adolescentes, observou-se um efeito inverso entre o consumo de ultra-processados e a pressão arterial sistólica explicado pelo efeito supressor do índice de massa corporal sobre a pressão arterial, que evidenciou um efeito que não é derivado do consumo alimentar e sim do aumento de peso. Entre os adultos, observou-se uma relação de dependencia entre o grau de processamento de alimentos e razão potássio sódio com IMC que, provavelmente devido falta de poder não pode ser evidenciada.
Concluiu-se portanto, que o grau de processamento de alimentos associa-se positivamente com o teor de energia, fibras e micronutrientes da dieta. Em adolescentes o consumo de alimentos ultra-processados é inverso a pressão arterial, no entanto este efeito deveu-se ao efeito supressor do IMC, e entre adultos não houve efeito direto e independente do grau de processamento de alimentos sobre a pressão arterial mas há um signficiativo efeito de interação com o IMC. Reforça-se que este é o primeiro estudo avaliando o efeito do grau de processamento dos alimentos sobre a pressão arterial e devido a potenciais limitações derivadas do delineamento, estimativas da ingestão de ingredientes e do tamanho amostral, que não considerou a priori estratificações por IMC, novos estudos devem ser encorajados.
Palavras-Chave:
Processamento de alimentos, pressão arterial, alimentos processados, pressão arterial, hipertensão arterial.
Abstract:
Objective: This study evaluated the relationship between the degree of food processing and the nutrient content of the diet and tested the relationship between the degree of processing and blood pressure in adolescents and adults of Porto Alegre.
Methods: The hypothesis was tested in a transversal study, with a probabilistic sample, where 599 adolescents and 1685 adults were recruited, participants of the SOFT study (A study on the obesity syndrome and cardiovascular risk factors). In a sub-sample of adolescents and adults, recruited with the intention to validate the questionnaire on frequency of food consumption (FFQ), diet was evaluated via two consecutive 24-hour dietary recalls (24h-DR). Information from the 24h-DR was used to break down recipes and estimate the intake of culinary ingredients. Foods were aggregated in three groups: unprocessed, moderately processed and ultra-processed, which were analyzed in grams per day in tertiles (grams per day) and food patterns based on the combination of the three food groups were compared to the DASH diet eating plan recommendation (Dietary Approach to Stop Hypertension). Adolescents and adults of the SOFT study were evaluated with the same FFQ, with 136 items. Weight and height were obtained with calibrated equipment, in standardized form, by certified research assistants. Blood pressure measurements were realized during the interview, utilizing an oscillometric monitor and a mean of four calibrations were used in the analysis. Information on sex, age, education level, physical activity, smoking habits, alcohol consumption was obtained with a standardized questionnaire. All of the participants signed the term of free and clear consent. Statistical analysis was based on generalized linear models.
Results: This study showed that the intake of moderately processed foods is greater among men and adult individuals of both sexes and the intake of ultra-processed foods reduces with age. The greater the degree of processing, the greater the energy and carbohydrate content of the diet. The consumption of unprocessed foods is associated with an elevated content of proteins, fibers, calcium and magnesium. Moderately processed foods results in higher fat and sodium content. While the elevated potassium content is clearly explained by the consumption of unprocessed foods, the contrary occurs with sodium. The intake of proteins, fibers, calcium, magnesium and potassium was directly related with the increase in consumption of unprocessed foods. The intake of moderately processed foods was inversely related with the calcium content, and there was a tendency to associate directly with sodium content; whereas, the intake of ultra-processed foods was negatively related with fiber and potassium. The dietary fiber, magnesium, and potassium contents were clearly improved when the food pattern was composed of a higher intake of unprocessed foods and a lower intake of moderately and ultra-processed. It was unlikely to achieve the target recommendation of sodium and energy when there was a higher intake of ultra-processed combined with a lower intake of unprocessed food products.
Among adolescents, in analyzing the consumption of foods classified by processing degree in grams per day, there was an inverse relationship between consumption of ultra-processed foods and systolic blood pressure. In combining the three food groups, the systolic blood pressure was 4.6 mmHg (P=0.01) higher among adolescents with lower intake of the three foods groups in comparison to those who have a diet with lower intake of unprocessed foods (1st tertile), intermediate intake of moderately processed (2nd tertile) and higher intake of ultra-processed foods (3rd tertile) The diastolic blood pressure was not different according to food groups combination.
Among adults, there was no association between the systolic and diastolic blood pressures according to increase, in tertiles, in consumption of unprocessed, moderately processed and ultra-processed foods, and there was a significant effect of interaction between the processing degree and body mass index. In testing combinations of food groups, we observed that the systolic blood pressure was 7.7 mmHg lower for individuals with lower intake of all the three food groups (1st tertile) in comparison to those who diet had lower intake of unprocessed (1st tertile), and higher intake of moderately and ultra-processed (3rd tertile). In comparing the systolic blood pressure of those who had lower intake of the three food groups and who consumed lower amounts of unprocessed and ultra-processed food products and higher amounts of moderately, the SBP was equally higher (130,2 and 130.1 mmHg).
Conclusions: We conclude, therefore, that the degree of food processing influences the energy, fiber and micronutrient content of the diet. In adolescents, the consumption of ultra-processed foods was inversely related to blood pressure. Among adults, there was an interaction between body mass index and the degree of food processing. Among adolescents and adults, the combination of food groups is significantly associated with blood pressure variations. For both, a greater consumption of moderately and ultra-processed foods in detriment of unprocessed foods in total food intake, is associated with reduced systolic blood pressure levels. We highlight that this is the first study evaluating the effect of the degree of food processing on blood pressure and the design of this study implies potential limitations.
Keyword:
Food processing, blood pressure, processed foods, blood pressure, arterial hypertension.