Mixed
Food Frequency Questionnaires (FFQs) and 24-hour recalls significantly underreport total energy intake and sodium intake compared to objective biomarkers (Doubly Labeled Water and urinary sodium).
Self-reported food diaries and questionnaires consistently underestimate how much you eat and how much salt you consume. If you are tracking sodium or calories, assume your report is lower than reality. Use this knowledge to be cautious with self-reported data for health decisions.
Compared with biomarkers, total energy intake, sodium intake, and sodium density were underreported by all self-reporting methods.
Why this rating
Validated against DLW (gold standard for energy) and urinary sodium (recovery biomarker).
Source
Relative Validity of Nutrient Intakes Assessed by Questionnaire, 24-Hour Recalls, and Diet Records as Compared With Urinary Recovery and Plasma Concentration Biomarkers: Findings for Women
Changzheng Yuan et al. · American Journal of Epidemiology · 2017
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