Measured and predicted resting metabolic rate in Italian males and females, aged 18–59 y

Abstract

Objectives: To determine the resting metabolic rate in a sample of the Italian population, and to evaluate the validity of predictive equations for resting metabolic rate (RMR) from the literature in normal and obese subjects.

Design: Cross-sectional observational study.

Settings: Department of Human Physiology and Nutrition, University ‘Tor Vergata’, Rome.

Subjects: A total of 320 healthy subjects, 127 males and 193 females, aged 18–59 y.

Methods: Weight, height and resting metabolic rate by indirect calorimetry were measured. Resting metabolic rate was also predicted using equations from the literature.

Results: Resting metabolic rate (mean±s.d.) in normal weight subjects was 7983±1007 kJ/24 h (males) and 6127±907 kJ/24 h (females). Measured RMR and predicted RMR values using various equations from the literature were significantly different in males and females, except for the Harris–Benedict equation and the Schofield equations. Also, in overweight and obese subjects the prediction error was generally larger compared to normal-weight subjects for all formulas except for the Harris–Benedict and Schofield formulas. In overweight and obese males but not in females, RMR was lower than in normal-weight subjects after correcting for weight and age differences. Stepwise multiple regression of resting metabolic rate against weight, height and age in males and females did not reveal a prediction formula with a lower prediction error than the Harris–Benedict or Schofield formulas and thus was not further explored.

Conclusions: The Harris–Benedict formula and the Schofield formula provide a valid estimation of resting metabolic rate at a group level in both normal-weight and overweight Italians. However, the individual error can be so high that for individual use a measured value has to be preferred over an estimated value.

European Journal of Clinical Nutrition (2001) 55, 208–214