Adherence
Food frequency questionnaires (FFQs) tend to overestimate carotenoid intake compared to weighed dietary records, potentially by two- to three-fold, due to the long list of food choices and lack of correction factors.
When using Food Frequency Questionnaires (FFQs) to track carotenoid intake, be aware that they tend to overestimate actual consumption by two- to three-fold compared to more precise methods like photographic atlases or weighed records. However, FFQs are still valuable for comparing relative intake between different populations or tracking changes over time, as the qualitative ranking of food sources remains accurate. Do not rely on FFQ data for precise dosing calculations.
One of the factors which may account for the high intakes observed using the FFQ method, may be a tendency to overestimate the consumption of vegetables and fruits when presented with a long list of choices... Recently Carroll et al. (1999) used the carotenoid intakes of the same subjects reported in this study, to compare with information obtained from dietary records estimated with the aid of a photographic atlas. The atlas technique gave estimates for the carotenoid intake which were two- to three-fold lower than those obtained using the FFQ.
Why this rating
The paper explicitly compares FFQ results with photographic atlas/weighed record estimates within the same cohort, providing direct evidence of the overestimation.
Source
A European carotenoid database to assess carotenoid intakes and its use in a five-country comparative study
M. E. O'Neill et al. · British Journal Of Nutrition · 2001
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