Revision of Dietary Reference Intakes for energy in preschool-age children

Background: Dietary Reference Intakes (DRI) for energy aim to balance energy expenditure at a level of physical activity consistent with health and support adequate growth in children. DR's were derived from total energy expenditure (TEE) measured by using the doubly labeled water (DLW) method; however, the database was limited in the 3-5-y-old range. Objective: We reexamined the DRI for energy for preschool-age children. Design: Ninety-seven healthy, normal-weight, preschool-age children (mean +/- SD age: 4.5 +/- 0.9 y) completed a 7-d DLW protocol while wearing accelerometer and heart rate monitoring devices. Results: Mean TEE and physical activity level (PAL) averaged 1159 +/- 171 kcal/d and 1.34 +/- 0.14, respectively. TEE predicted by DR1 equations agreed with observed TEE (+34 kcaUd or 3%) if the sedentary PAL category was assumed but was overestimated by using the low active (+219 kcal/d or 19%), active (398 kcal/d or 34%), and very active (593 kcaUd or 51%) PAL categories. PAL categories were redefined on the basis of the narrower PAL range observed in preschoolers (range: 1.05-1.70) compared with older children and adults (range: 1.0-2.5). Sex-specific nonlinear regression models were newly developed to predict TEE from age, weight, height, and new PAL categories. The mean absolute error of TEE prediction equations was 0.00 +/- 35 kcal/d or 0.1 +/- 3%. Ancillary measures, such as total accelerometer counts and total daily steps, that were significantly correlated (P = 0.01-0.05) with TEE (r = 0.26-0.38), TEE per kilogram (r = 0.31-0.41), and PAL (r = 0.36-0.48) may assist in the classification of preschoolers into PAL categories. Conclusions: Current DRIs for energy overestimate energy requirements of preschool-age children because of the erroneous classification of children into PAL categories. New TEE prediction equations that are based on DLW and appropriate PAL categories are recommended for preschool-age children.