Capturing the true dietary intake of groups of individuals is challenging, and every assessment technique has its flaws. Although the tools used in this study have been extensively validated and compared with other tools,11-15,43 food fre- quency questionnaires in general have been shown to both underestimate44 and overestimate intake in individuals.45
The benefit to use of food frequency questionnaires is that they tend to capture intake patterns over time compared with
24-hour recalls or records that can alter intake and are less representative of overall intake patterns. In addition, the food frequency tool has been shown recently to be suitable for testing many diet– disease associations