BMR variability in women of different weight

Summary Background & aims Non-exercise activity thermogenesis (NEAT) and substrate oxidation are significant components of Energy Balance; their regulation may be modulated according to nutritional status and their impairment has been advocated as a factor facilitating the development of excess body fat. Methods In this study body composition, resting metabolic rate (RMR), fidgeting as a component of NEAT and respiratory quotient (RQ), an index of preferential substrate oxidation, have been evaluated in 80 young women: 20 restrictive anorexia nervosa (rAN: BMI 15.1±1.6 kg/m 2 ); 20 constitutional leanness (CL: BMI 17.2±1.0); 20 obese patients (Ob: BMI 43.8±10.0) and 20 controls (CTR: BMI 21.7±2.4). Results Fat free mass, fat mass and RMR progressively increased from rAN to Ob ( p p r =−0.433; p r =0.572; p r =0.434; p Conclusion Our findings support the regulatory function of NEAT, its protective role to prevent excess body fat accumulation and its positive relation with fat oxidation in CL.