Energy Expenditure In The Etiology Of Obesity
Cross-sectional studies that compare lean and obese individuals have added little to our understanding of the physiological mechanisms predisposing to weight gain (76). An understanding of the etiology of human obesity demands longitudinal studies to reveal predictors or risk factors. Several studies have prospectively examined these predictors in the Pima Indian population in southwestern Arizona, a population where obesity is extremely prevalent (77) and, therefore, weight gain is common in young adults. In these individuals at least six metabolic parameters have been found to be predictive of weight gain. In particular, related to energy expenditure and relevant to understanding the etiology of obesity, are low metabolic rate, low activity thermogenesis, low sympathetic nervous system activity, and low fat oxidation.