Relationship of high energy expenditure and variation in dietary intake with reporting accuracy on 7 day food records and diet histories in a group of healthy adult volunteers.

OBJECTIVES: To assess the accuracy of reporting from both a diet history and food record and identify some of the characteristics of more accurate reporters in a group of healthy adult volunteers for an energy balance study.
DESIGN: Prospective measurements in free-living people.
SETTING: Wollongong, Australia.
SUBJECTS: Fifteen healthy volunteers (seven male, eight female; aged 22-59 y; body mass index (BMI) 19-33 kg/m(2)) from the local community in the city of Wollongong, Australia.
INTERVENTIONS: Measurement of energy intake via diet history interview and 7 day food records, total energy expenditure by the doubly labelled water technique over 14 days, physical activity by questionnaire, and body fat by dual-energy X-ray absorptiometry.
RESULTS: Increased misreporting of energy intake was associated with increased energy expenditure (r=0.90, P<0.0001, diet history; r(S)=0.79, P=0.0005, food records) but was not associated with age, sex, BMI or body fat. Range in number of recorded dinner foods correlated positively with energy expenditure (r(S)=0.63, P=0.01) and degree of misreporting (r(S)=0.71, P=0.003, diet history; r(S)=0.63, P=0.01, food records). Variation in energy intake at dinner and over the whole day identified by the food records correlated positively with energy expenditure (r=0.58, P=0.02) and misreporting on the diet history (r=0.62, P=0.01).
CONCLUSIONS: Subjects who are highly active or who have variable dietary and exercise behaviour may be less accurate in reporting dietary intake. Our findings indicate that it may be necessary to screen for these characteristics in studies where accuracy of reporting at an individual level is critical.