Comparable diet recall accuracy between dieters and non-dieters participating in feeding studies

Validation of diet assessment methods has been limited by the lack of a true gold standard. Direct observation has been considered as one of the nearest gold standards available, and has been employed over short time periods only (1 to 5 days). Since dieters in particular have been suggested to have poor recall of food intake, we assessed the accuracy of diet recall using the Block food frequency questionnaire (FFQ) in a group of dieters (n=20) and weight maintainers (n=21) after participation in a controlled feeding study for 4 and 6 weeks, respectively. Without prior notice, subjects completed the FFQ 3 weeks after completing their feeding protocol and were instructed to report the frequency of foods eaten during the study from memory only. Weekly frequency was calculated and compared to that calculated from the study menu by a nutritionist. For 75% of the 60 food items assessed, average memory recall was within a frequency deviation of <1 per week. Greater variation was notable only on 25% of the food items. Finding from this small sample reconfirms that FFQ is appropriate for assessing population intakes. However, percent of food items recalled within a frequency deviation of <1 per week was similar between dieters (70%) and non-dieters (75%). This result contradicts earlier reports that dieters are unaware of eating behavior or have difficulty in recalling food intakes.

Duke Scholars

Author Pao-Hwa Lin Medicine, Nephrology