Measurement of Resting Energy Expenditure with Indirect Calorimetry and Predictive Equations in Healthy Young Adults: A Cross-sectional Study

Abstract

Introduction: Resting Energy Expenditure (REE) is the main determinant of energy requirements. An inaccurate estimation of REE can lead to the over or under-prediction of energy requirements. Indirect calorimetry is considered as the gold standard for the assessment of REE. The most of the predictive equations which are formed, are from the studies conducted on Caucasian people while on Asian population these studies are very limited. Aim: To compare the REE measured by indirect calorimetry and predictive equation in healthy young adults. Materials and Methods: A cross-sectional study was done on 100 healthy young adult participants from November 2018 to May 2019, of age group 18 to 25 years to measure REE using indirect calorimetry and predictive equations (Harris-Benedict’s, Schofield, FAO/WHO/UNU and Mifflin-St. Jeor equations). Statistical analysis was carried out using SPSS version 16.0. Unpaired student t-test for comparison of data and Bland Altman test to check for validity of predictive equations were applied. Results: The mean value of REE using Indirect calorimetry was 1994.20±577.33 and that of using four Harris-Benedict’s, Schofield, FAO/WHO/UNU and Mifflin-St.Jeor equations were 1638.15±335.64 kcal/day, 1636.21±359.85 kcal/day, 1636.93±367.59 kcal/day and 1582.41±251.29 kcal/day, respectively. Thus, the highest mean difference between values of REE obtained using predictive equation and indirect calorimetry was 411.79±326.04 kcal/day with respect to Mifflin-St.Jeorand’s and the lowest mean difference was 356.05±241.69 kcal/day with respect to Herris Benedict’s equation. Conclusion: Predictive equations underestimated the REE of young adults when compared with that measured by indirect calorimetry.