THE EFFECTS OF FAT DISTRIBUTION ON RESTING ENERGY-EXPENDITURE IN PREMENOPAUSAL MORBIDLY OBESE FEMALES

Background: upper body, or abdominal, distribution of body fat is asso ciated with a number of metabolic and hormonal aberrations that could influence resting energy expenditure REE. The purpose of our study was to examine the effects of fat distribution on REE of 96 morbidly obes e premenopausal females. Methods: the study population consisted of th ree groups of study subjects, 32 with lower body fat distribution (LBD ) and waist-to-hip circumference ratios WHR < 0.80, 20 with intermedia te (INT) fat distribution and WHR between 0.80 and 0.85 and 34 females with upper body distribution of fat (UBD) and WHR > 0.85. Indices mea sured included: (1) REE; (2) maximal oxygen consumption during an exer cise tolerance test (VO2max); (3) basal respiratory quotient (RQ); (4) fasting blood glucose; and (5) serum cholesterol and triglycerides. R esults: we found that morbidly obese women who store fat abdominally ( WHR > 0.80) have significantly (rho < 0.01) higher REE (kcal per h per BSA) than those with lower body obesity. Levels of triglyceride and g lucose of the UBD group were also higher than those of the LBD subject s, i.e. 35% and 23%, respectively. VO(2max) and RQ were similar betwee n the study groups, suggesting that the elevated REE of the patients w ith abdominal adiposity were likely not the result of their greater mu scle mass or differences in substrate utilization. Conclusion: fat dis tribution affects REE in morbidly obese premenopausal females, and fur ther research is needed to identify the various entities regulating RE E in the morbidly obese.