Issue 137 Item 8 Body Fat Distribution Affects Insulin Level In Children

An increase in subcutaneous abdominal fat appears to increase fasting insulin levels in growing children, according to a report in Obesity Research. Terry T. K. Huang and colleagues at the University of Southern California and the University of Alabama at Birmingham measured fasting insulin concentration, insulin sensitivity, and fat distribution in 77 children whose mean age at baseline was 8.3 years. Fasting insulin and insulin sensitivity measures occurred at least three times each year for 3 years.

A significant association between fasting insulin level and increase in visceral fat, independent of subcutaneous abdominal fat, was found. For every 1 cm2/yr increase in visceral fat, fasting insulin increased by approximately 5% (p<0.05).

A similar relation existed between fasting insulin concentration and subcutaneous abdominal fat, independent of visceral fat. For every 1 cm2/yr increase in subcutaneous abdominal fat, fasting insulin increased by approximately 2% (p<0.02).

No relation was found between an increase in fat and insulin sensitivity (Effect of changes in fat distribution on the rates of change of insulin response in children. "The rate of change in visceral fat was positively associated with the rate of change in fasting insulin, independent of increasing subcutaneous abdominal fat; however, subcutaneous abdominal fat may be more predictive of the rate of change of fasting insulin than visceral or total fat," concluded Huang and associates. "Therefore, growth-related increases in abdominal fat, particularly subcutaneous abdominal fat, may contribute to accelerating increases in fasting insulin, but have no effect on insulin sensitivity."

Key points reported in this study include:

* For every 1 cm2/year increase in visceral fat, an increase of 5% was seen in fasting insulin concentration, independent of subcutaneous abdominal fat

* For every 1 cm2/year increase in subcutaneous abdominal fat, an increase of 2% was seen in fasting insulin concentration, independent of visceral fat

* Insulin sensitivity did not correlate with amount of visceral or subcutaneous abdominal