Adherence
Self-reported energy intake significantly underestimates actual energy expenditure, with the magnitude of under-reporting increasing with body weight and adiposity.
Do not rely on self-reported food logs to determine your actual calorie intake, especially if you are overweight. These logs systematically underestimate intake by 20-50% in obese individuals. Use objective measures like body weight trends or doubly labelled water (if available) instead of self-reports for research or precise clinical assessment.
The bias is largest in obese adolescents and smallest in lean adults living in industrialized countries.
Why this rating
Based on a review of 9 studies using the doubly labelled water method, a gold-standard objective measure, though some studies were abstracts.
Source
Inaccuracies in self-reported intake identified by comparison with the doubly labelled water method
Dale A. Schoeller et al. · Canadian Journal of Physiology and Pharmacology · 1990
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