Arife DEMİR, Ayşe Nur KAHVE, Ebru BAYRAK
Food and Health - 2026;12(4):318-332
This study aims to systematically compare the amount of dietary phytochemicals in adults aged 20-65 years using different calculation methods and dietary assessment tools. Data were collected from a total of 430 individuals using a 24-hour dietary recall and food frequency questionnaire; phytochemical intake was calculated using the USDA, Phenol-Explorer, and Phytochemical Index methods. The findings showed significant and statistically significant differences between the methods and assessment tools (p<0.001). The PE method systematically produced higher estimates, while the FI method produced lower estimates, and a very high method x tool interaction was detected. These results highlight the crucial role of methodological choice in estimating phytochemical intake and emphasize that the lack of standardization in inter-study comparisons is a significant limitation. The use of multiple methods and ensuring methodological consistency are critical for future research.
