The influence of age and body mass index on relative accuracy of energy intake among Japanese adults

OBJECTIVE: To examine relationships between the ratio of energy intake to basal metabolic rate (EI/BMR) and age and body mass index (BMI) among Japanese adults. DESIGN: Energy intake was assessed by 4-day semi-weighed diet records in each of four seasons (16 days in total). The EI/BMR ratio was calculated from reported energy intake and estimated basal metabolic rate as an indicator of reporting accuracy. SETTING: Residents in three areas in Japan, namely Osaka (urban), Nagano (rural inland) and Tottori (rural coastal). SUBJECTS: One hundred and eighty-three healthy Japanese men and women aged > or =30 years. RESULTS: The oldest age group (> or =60 years) had higher EI/BMR values than the youngest age group (30-39 years) in both sexes (1.74 vs. 1.37 for men; 1.65 vs. 1.43 for women). In multiple regression analyses, age correlated positively (partial correlation coefficient, beta = 0.012, P < 0.001 for men; beta = 0.011, P < 0.001 for women) and BMI correlated negatively (beta = -0.031, P < 0.001 for men; beta = -0.025, P < 0.01 for women) with EI/BMR. CONCLUSION: Age and BMI may influence the relative accuracy of energy intake among Japanese adults.