BMR variability in women of different weight.
OBJECTIVE
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 < 0.05). Fidgeting was higher in CL (67.2+/-27.2 kcal; p < 0.05) than in the other groups. Lipid oxidation, evaluated with RQ showed a negative correlation with fidgeting in CL (r=-0.433; p<0.05) and positive in Ob (r=0.572; p<0.05) and in rAN (r=0.434; p<0.05).


CONCLUSIONS
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.
Marra
Maurizio
M
Interuniversity Center for Obesity and Eating Disorders, Department of Clinical and Experimental Medicine, Federico II University, 80131 Naples, Italy. marra@unina.it
Pasanisi
Fabrizio
F
Montagnese
Concetta
C
De Filippo
Emilia
E
De Caprio
Carmela
C
de Magistris
Lanfranca
L
Contaldo
Franco
F
D000273:Adipose Tissue / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D000856:Anorexia Nervosa / Q000378:metabolism; D001481:Basal Metabolism / Q000502:physiology*; D001823:Body Composition / Q000502:physiology; D001835:Body Weight / Q000502:physiology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D009043:Motor Activity / Q000502:physiology; D009752:Nutritional Status; D009765:Obesity / Q000378:metabolism; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D022722:Thermogenesis / Q000502:physiology*; D013851:Thinness / Q000378:metabolism