UNDERREPORTING AND OVERREPORTING OF ENERGY-INTAKE RELATED TO WEIGHT STATUS AND LIFE-STYLE IN A NATIONWIDE SAMPLE

Desire for weight change and level of dietary consciousness may severe ly bias reported food intake in dietary surveys. We evaluated to what degree under- and overreporting of energy intake (EI) was related to l ifestyle, sociodemographic variables, and attitudes about body weight and diet in a nationwide dietary survey. Data. were gathered by a self -administered quantitative food-frequency questionnaire distributed to a representative sample of men and women aged 16-79 y in Norway, of w hom 3144 subjects (63%) responded. Reported EI was related to estimate d basal metabolic rate (BMR) based on self-reported body weight, age, and sex. An EI:BMR <1.35 was considered to represent underreporting an d an EI,BMR greater than or equal to 2.4 as overreporting of EI, Fewer men than women underreported EI (38% compared with 45%). The fraction of overreporters: did not differ significantly between sexes (7% of t he men compared with 5% of the women). A large proportion of underrepo rters was obese (9%) and wanted to reduce their weight (41%). Few over reporters were obese and 12% wanted to increase their weight. Underrep orters consumed fewer foods rich in fat and sugar than did the other s ubjects. Multiple regression analysis showed that desire for weight ch ange and physical activity score were significantly correlated with bo th Fl and EI:BMR when adjusted for sociodemographic and lifestyle vari ables. Our findings indicated that attitudes about one's own body weig ht influenced reported EI. These attitudes are important in the interp retation of dietary data because many of the subjects (>30%) wanted to change their body weight.