Overgrowth: energetic significance in relation to obesity
James, W.P.; Sahakian, B.J.
Progress in Clinical and Biological Research 61: 25-53
1981
ISSN/ISBN: 0361-7742 PMID: 7033975 Document Number: 179747
Childhood prevalence of obesity, hereditary and metabolic bases of obesity, and the concept of energy balance in obesity are reviewed. The results of animal experimentation on the ob/ob mouse (which exhibits both hyperphagia and an increased metabolic efficiency connected with obesity) and its brown adipose tissue metabolism are considered in detail. Non-shivering thermogenesis (NST) in humans is also treated, since it has been recognized that brown adipose tissue in the newborn child plays an important role in maintaining body temperature. Tests of the relationship of NST to obesity (conducted in obese and lean females under a limited food intake to avoid weight gain) showed that obese subjects had a similar metabolic response to noradrenaline which was only half that of lean subjects; this paralleled results obtained in animal studies. It is possible that brown adipose tissue metabolism is responsible for NST in adult humans as well as in adult rodents. Further, the sequence of changes in energy expenditure does not exclude the hyperphagic child or adult, but (as with the ob/ob mouse) it is important to distinguish between altered metabolic efficiency and hyperphagia. Additional factors in the interrelation of energy intake and obesity are discussed. (wlz)