Changes in insulin and corticosterone levels may partly mediate the hypolipidemic effect of guar gum and low-molecular weight pectin in rats

The effects of guar gum and a low-molecular weight pectin (LMM-pectin) on growth-rates and postprandial plasma triacylglycerol (TAG), total cholesterol (TCh), glucose, insulin, glucagon and corticosterone levels were investigated in rats. After 8 days of adaptation, rats were fed diets containing either sucrose (Controls) or experimental fibers for three weeks. Compared with controls, rats fed soluble fibers showed a significant decrease of TAG, TCh and insulin concentrations without changes in postprandial blood glucose levels. Glucagon was up-regulated. Compared to rats fed LMM-pectin, a significant decrease (-61%) of postprandial corticosterone was observed in rats fed guar gum. It is suggested that the decrease of corticosterone and insulin levels may partly explain the more important hypolipidemic effect observed in this group. (C) 2001 Elsevier Science Inc. All rights reserved.