Food frequency questionnaire for adults in the Brazilian Northeast region: emphasis on the level of food processing

OBJECTIVE: To develop a quantitative Food Frequency Questionnaire (FFQ) for adults in the Northeast region of Brazil, in order to identify the frequency of consumption of foods considered to be of protection and risk for chronic non-communicable diseases (NCDs), grouping food items by processing level. METHODS: To develop the FFQ, data from 7,516 adults from Northeastern Brazil were used, extracted from the 2008–2009 Household Budget Survey. The food lists were elaborated according to the methodology of the relative contribution of each item, identifying foods with the highest relative contribution for macronutrients, fiber, saturated fat, trans fat, sodium and potassium. All foods whose contribution sum was up to 90% composed such lists. The final structure of the FFQ organized the food items in order to respect the mental image of the meals. RESULT: The FFQ resulted in 83 food items, distributed in minimally processed, processed and ultra-processed. We chose the previous year as the time to estimate food consumption, and frequency options ranged from “never” to “10 times”. The instrument includes guidelines for filling and collects data on serving sizes (small, medium, large and extra-large), as well as additional information on culinary preparations. There was a high percentage of people who were overweight (44.1%). CONCLUSION: The study culminated in an FFQ to identify the frequency of consumption of foods considered protective and risk for NCDs. The instrument can support epidemiological studies that evaluate outcomes related to the diet of adults considering the level of food processing, in accordance with the Guia alimentar para a população brasileira .