Comparison of dietary phytochemical intake in adults using different assessment methods

Abstract

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 × 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.

Keywords

• Dietary phytochemicals
• Phytochemical index
• Phenol-Explorer
• Diet assessment methods

Ethical Statement

The study was conducted following the Declaration of Helsinki Principles. To carry out the research, the approval of the Selçuk University Faculty of Health Sciences Ethics Committee for Non-Interventional Clinical Investigations was obtained (2023/645).

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