title: Measuring the difference between actual and reported food intakes in the context of energy balance under laboratory conditions.
abstract: To date, no study has directly and simultaneously measured the discrepancy between what people actually eat and what they report eating under observation in the context of energy balance (EB). The present study aimed to objectively measure the 'extent' and 'nature' of misreporting of dietary intakes under conditions in which EB and feeding behaviour were continuously monitored. For this purpose, a total of fifty-nine adults were recruited for 12 d, involving two 3 d overt phases and two 3 d covert phases of food intake measurement in a randomised cross-over design. Subjects had ad libitum access to a variety of familiar foods. Food intake was covertly measured using a feeding behaviour suite to establish actual energy and nutrient intakes. During the overt phases, subjects were instructed to self-report food intake using widely accepted methods. Misreporting comprised two separate and synchronous phenomena. Subjects decreased energy intake (EI) when asked to record their food intake (observation effect). The effect was significant in women ( - 8 %, P< 0·001) but not in men ( - 3 %, P< 0·277). The reported EI was 5 to 21 % lower (reporting effect) than the actual intake, depending on the reporting method used. Semi-quantitative techniques gave larger discrepancies. These discrepancies were identical in men and women and non-macronutrient specific. The 'observation' and 'reporting' effects combined to constitute total misreporting, which ranged from 10 to 25 %, depending on the intake measurement assessed. When studied in a laboratory environment and EB was closely monitored, subjects under-reported their food intake and decreased the actual intake when they were aware that their intake was being monitored.
authors.affiliation: Rowett Institute of Nutrition and Health, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, UK.
authors.forename: R James
authors.initials: RJ
authors.lastname: Stubbs
authors.affiliation: Rowett Institute of Nutrition and Health, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, UK.
authors.forename: Leona M
authors.initials: LM
authors.lastname: O'Reilly
authors.affiliation: Public Health Nutrition Research Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen AB25 2ZD, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Whybrow
authors.affiliation: Rowett Institute of Nutrition and Health, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, UK.
authors.forename: Zoë
authors.initials: Z
authors.lastname: Fuller
authors.affiliation: Rowett Institute of Nutrition and Health, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, UK.
authors.forename: Alexandra M
authors.initials: AM
authors.lastname: Johnstone
authors.affiliation: University of Ulster at Coleraine, Cromore Road, Coleraine, County Londonderry, Northern Ireland, UK.
authors.forename: M Barbara E
authors.initials: MB
authors.lastname: Livingstone
authors.affiliation: UMR Inserm 1027, Université Paul Sabatier, CHU de Toulouse, France.
authors.forename: Patrick
authors.initials: P
authors.lastname: Ritz
authors.affiliation: Biomathematics and Statistics Scotland, The Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, UK.
authors.forename: Graham W
authors.initials: GW
authors.lastname: Horgan
mesh_terms: D000328:Adult; D000368:Aged; D001823:Body Composition; D015992:Body Mass Index; D018592:Cross-Over Studies; D015930:Diet Records; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D004435:Eating; D002149:Energy Intake; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D015203:Reproducibility of Results; D057566:Self Report; D055815:Young Adult
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins