| dc.description.abstract |
Distribution as well as amount of fat has health implications; centralabdominal fat seems to be the major contributor to insulin resistance and riskof diabetes, hypertension and cardiovascular disease. Physical activity anddiet affect overall adiposity; moreover, exercise specifically reducesvisceral fat. The sexes differ in fat distribution; in particular,pre-menopausal women, despite greater overall adiposity, have much lessvisceral fat than men. There is a strong genetic determination of overallobesity and central abdominal adiposity. Genes regulating obesity (e.g.Ob) could modulate appetite, satiety, metabolic rate orphysical activity. Moderate obesity probably results from interaction betweengenetic predisposition and an environment of abundant calories and reducedphysical activity. Single gene mutations are being identified in a fewmorbidly obese people; however, the common genetic predisposition for obesitymay relate to more subtle variations in regulatory controls.Diet and exercise are effective for some, but the response is oftendisappointing. Definition of pathways controlling appetite, metabolic rate andlipid metabolism may generate improved pharmacological compounds. Educationand availability of lower-energy foods may help, but more radical approachesmay be needed, such as environmental restructuring to increase physicalactivity. The problem is great, but failure will mean intolerably increasedhealth costs. |
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