DOSE-RESPONSE TO SOLUBLE FIBER FROM PSYLLIUM IN CHOLESTEROL-LOWERING IN THE HAMSTER

Dose response in serum and liver lipids to graded levels of soluble fiber primarily from psyllium was studied in five groups of hamsters fed diets supplemented with 0.125% cholesterol and 1.1%, 2.1%, 3.3%, and 4.3% psyllium soluble fiber for three weeks. Compared to the control group fed AACC soft white wheat bran only, all psyllium-fed groups had significant reduction in serum total cholesterol and HDL-cholesterol (p<0.0001) but there were no significant changes in triglycerides and HDL: total cholesterol ratios. Mean reduction in serum total cholesterol relative to the control group in response to graded doses of psyllium in the diet was linear (r = 0.99, p < 0.001), equivalent to 11% reduction per gram of soluble fiber from psyllium. Differences in liver weight and concentration of liver lipids (free cholesterol, esterified cholesterol, triglycerides, total lipids) were significant among groups (p<0.005). Liver weight, esterified cholesterol and total lipids (mg/g liver) were correlated positively (r=0.60, 0.85, 0.66 respectively, p<0.0001), but liver triglycerides negatively (r=-0.34, p<0.005), with serum total cholesterol.