Is the metabolic syndrome a useful concept?

✍ Scribed by John Stanley

• Publisher: Wiley (John Wiley & Sons)
• Year: 2007
• Tongue: English
• Weight: 759 KB
• Volume: 19
• Category: Article
• ISSN: 0956-666X
• DOI: 10.1002/lite.200700070

✦ Synopsis

Abstract

Not all obese individuals are insulin resistant while individuals who fail to develop adequate adipose tissue mass, a rare disorder called lipodystrophy, are insulin resistant. These observations suggest that the relationship between body fat and insulin resistance is complex. This relationship can be explained by considering body fat distribution. According to one idea visceral fat is characterised by the overproduction of fatty acids which stimulate glucose production by the liver and inhibit glucose use by skeletal muscle and the underproduction of adipokines such as adiponectin which improve insulin resistance. Hence individuals with excess visceral fat become insulin resistant. According to a second idea excess visceral fat is a marker for dysfunctional adipose tissue. Energy in excess of requirements is normally stored as triacylglycerols in subcutaneous fat. If this is defective then triacylglycerols are stored at other ectopic sites leading to impaired function. Obese individuals without insulin resistance store their triacylglycerols in subcutaneous fat and are protected. Individuals with lipodystrophy have no subcutaneous fat so they develop insulin resistance.