Use of a triaxial accelerometer to validate reported food intakes

Background: An easy and cheap method for validating reported energy intake (EI) is needed. Objective: Reported EI was compared with calculated energy expenditure (EEc alc) and with energy expenditure measured by the doubly labeled water metho d (EEDLW). Design: EE was calculated on the basis of basal metabolic rate (BMR) measur ed with the ventilated-hood technique and physical activity (PA) measured w ith a triaxial accelerometer (EEVH+PA) and on the basis of BMR estimated by using World Health Organization equations and PA (EEWHO+PA): EEcalc = -1.2 59 + 1.55 X BMR + 0.076 x counts/min (r(2) = 0.90, P = 0.0001). Subjects [n = 12 men and 12 women aged 60 +/- 3 y; body mass index tin kg/m(2)): 26 +/ - 4] reported their food intakes for 7 d and EEDLW, EHVH+PA, and EEWHO+PA w ere assessed over the same 7 d. Results: Reported EI (9.0 +/- 2.1 MJ/d) was lower (P < 0.0001) than were EE DLW (11.3 +/- 2.3 MJ/d), EEVH+PA (10.8 +/- 1.7 MJ/d), and EEWHO+PA (10.8 +/ - 1.8 MJ/d). Underreporting was 19.4 +/- 14.0%, 16.7 +/- 13.6%, and 16.4 +/ - 15.5% on the basis of EEDLW, EEVH+PA, and EEWHO+PA, respectively. The dif ference of 2.7 +/- 8.0% between EEDLW and EEVH+PA was not related to the av erage of both percentages and was not significantly different from zero. Th e percentage of underreporting calculated with EEWHO+PA was not significant ly different from that calculated with EEDLW. Conclusions: The use of a combination of BMR (measured or estimated) and PA is a good method for validating reported EI. There was no significant diff erence between the percentage of underreporting calculated with EEVH+PA, EE WHO+PA, or EEDLW.