Adherence
Traditional self-reported dietary instruments (diet recalls, diaries, FFQs) systematically underreport energy intake, with the magnitude of error increasing with BMI, thereby attenuating or reversing observed diet-disease relationships.
Do not rely on your memory of what you ate to calculate calories or track weight loss progress. Self-reported intake is consistently 16-30% lower than actual intake, especially if you are overweight. For accurate health insights, use objective biomarkers (like Doubly Labeled Water) or calibrated statistical corrections rather than self-reported food diaries.
The evidence demonstrates a strong and consistent systematic underreporting of energy intake (EIn) across adults and children studies. Underreporting of EIn has been found to increase with body mass index (BMI)... the between-individual variability in the underreporting of self-reported intake of energy and other nutrients attenuates diet–disease relationships.
Why this rating
Based on multiple large-scale validation studies using the doubly labeled water (DLW) biomarker, a gold-standard objective measure.
Source
Traditional Self-Reported Dietary Instruments Are Prone to Inaccuracies and New Approaches Are Needed
Michele Novaes Ravelli et al. · Frontiers in Nutrition · 2020
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