DIETARY METHODS RESEARCH IN THE 3RD NATIONAL-HEALTH AND NUTRITION EXAMINATION SURVEY - UNDERREPORTING OF ENERGY-INTAKE

Assessment of diet is a critical component of the third National Healt h and Nutrition Examination Survey (NHANES III), which was designed to describe the health and nutritional status of the US population. We a nalyzed data collected with the primary dietary assessment instrument used in NHANES III, the 24-h recall, for 7769 nonpregnant adults aged greater than or equal to 20 y to investigate underreporting of total e nergy intake. Underreporting was addressed by computing a ratio of ene rgy intake (EI) to estimated basal metabolic rate (BMR(est)). EI:BMR(e st) was 1.47 for men and 1.26 for nonpregnant women; a population leve l of 1.55 is expected for a sedentary population. About 18% of the men and 28% of the women were classified as underreporters. Underreportin g of energy intake was highest in women and persons who were older, ov erweight, or trying to lose weight. Underreporting varied according to smoking status, level of education, physical activity, and the day of the week the 24-h recall covered. Additionally, underreporting was as sociated with diets lower in fat (P < 0.01) and alcohol (P < 0.01 in w omen) when expressed as a percentage of total energy intake.