From 2017... Under-reporting of total energy intake is a common and well-known source of measurement error in dietary assessment; this bias is particularly significant in obese individuals

From 2017... People with a body mass index ⩾30 under-report their dietary intake: A systematic review. Helena Wehling, Joanne Lusher. Journal of Health Psychology, July 21, 2017. https://doi.org/10.1177/1359105317714318

Abstract: Under-reporting of total energy intake is a common and well-known source of measurement error in dietary assessment, and evidence suggests that this bias is particularly significant in obese individuals. After a multi-stage selection process of eligible papers, this literature review appraised 34 papers detailing the accuracy of self-reported dietary intake in people with an obese body mass index (BMI ⩾ 30). The available literature to date shows that having a body mass index ⩾30 is associated with significant under-reporting of food intake. Future research should look into identifying effective techniques to reduce this bias in clinical practice.

Keywords: 24-hour dietary recall, dietary intake, nutrition assessment, obesity, self-reported energy intake, under-reporting