BMR in a Brazilian adult probability sample: the Nutrition, Physical Activity and Health Survey

Objective: To measure BMR in a probability sample of adults from an urban city of Brazil and to compare indirectly measured BMR (BMRi) with BMR predicted from different equations. Design: BMR data were obtained by indirect calorimetry and estimated by different predictive equations (Schofield; Harris and Benedict; Henry and Rees). Anthropometric and body composition measures were also obtained. Setting: The Nutrition, Physical Activity and Health Survey (PNAFS), a household survey conducted in Niteroi, Rio de Janeiro state, Brazil. Subjects: Representative sample of 529 adults (aged >= 20 years; 339 females) living in Niteroi, Rio de Janeiro state, Brazil. Results: Mean BMRi values were 5839.7 (SE 73.9) kJ/d and 4758.1 (SE 39.5) kJ/d for men and women, respectively. Predicted BMR by all equations was significantly higher (difference between means and 95% CI did not include zero) than BMRi in both men and women of all ages. Overall bias in BMR (predicted BMR minus BMRi) using the Schofield equations (overestimation of about 20 %) was higher than when using the Henry and Rees equations (13% and 16% overestimation for males and females, respectively). The percentage of individuals whose BMR predicted by the Schofield equations fell within 10% of BMRi was very low (7.8% and 14.1% of males and females, respectively). Conclusions: Current available predictive equations of BMR are not adequate to estimate BMR in Brazilians living in Niteroi, Rio de Janeiro, Brazil.