Serum and liver lipids in rats fed 20% fat diets containing corn oil (CO) or cottonseed oil (CSO)

It has been previously demonstrated that rats fed a diet having 10% CSO have a lower serum cholesterol concentration but similar concentrations of serum triglycerides and liver cholesterol and triglycerides compared to ones fed a 10% CO diet. To determine the effect of CSO versus CO on lipid status, as well as the fecal excretions of neutral sterols (NS) and bile acids (BA), groups (n=10 each) of growing male Sprague‐Dawley rats were fed diets containing 20% CSO or CO for 28d. Relative to group CO, group CSO had a 10% lower serum concentration of cholesterol, a 20% lower excretion of NS, a 13% lower excretion of NS + BA, but there were no between group differences for serum triglycerides, the hepatic concentration of cholesterol or triglycerides, or BA excretion. Thus, CSO exerts a cholesterol‐lowering effect versus CO at a dietary fat level of 20%, despite a decreased excretion of NS + BA, indicating that the effect may be mediated via a decrease in cholesterol synthesis.