Comparison of dietary phytochemicals in adults with different assessment methods

Phytochemicals found in plant foods can be used as a preventive and therapeutic agent against many diseases that may occur as a result of oxidative stress. In order to evaluate the dietary intake of phytochemicals, databases such as phytochemical index, United States Department of Agriculture (USDA), Phenol-Explorer (PE) have been developed. When the studies in Turkey were examined, no study was found that evaluated dietary phytochemicals using databases. In this study, it was aimed to compare the dietary phytochemical intakes of adults aged 20-65 with two different dietary assessment tools, namely food consumption frequency questionnaire and 24-hour food consumption record, using phytochemical index, PE and USDA flavonoid database. This study was conducted on 430 individuals aged 20-65 living in the city center of Konya. The participants' sociodemographic characteristics and dietary habits were questioned with a questionnaire form, and a food consumption frequency questionnaire and food consumption records were taken to calculate the phytochemical content of the diet. The total phytochemical contents of the data were determined from the USDA and PE flavonoid databases by multiplying the daily consumption of food items with the polyphenol/flavonoid contents of these food items and calculating the phytochemical index (PI). A statistically significant difference was found between the food consumption record averages of USDA, PE and PI methods (p<0.001). This difference was observed among all methods. While the highest food consumption record average was obtained in PE with 432.05, the lowest average was determined in the PI method with 78.64. There is a statistically significant difference between the food consumption frequency values of USDA, PE and FI methods (p<0.001). This difference was observed among all methods. While the highest food consumption frequency median value was obtained in PE with 1414.78, the lowest median value was determined in the FI method with 82.57. The USDA and PE groups have the highest averages of vegetable, non-alcoholic beverage and fruit consumption. In USDA, consumption of grains, legumes, oilseeds and oil is low. In the PE group, consumption of legumes, oilseeds, cocoa and oil is low. The distribution by food groups in the USDA and PE databases is similar. In order to minimize the differences in the databases used to evaluate dietary intake of phytochemicals, they should be continuously updated with analytical research and dietary phytochemical consumption should be evaluated with the databases belonging to the countries. Keywords: Analysis; Dietary phytochemicals; Phenols; Phytochemical index