Comparative Effects of Dietary Palm Oil, Perilla Oil, and Soybean Oil on Lipid Profiles in Differently Aged Rats Fed on Hypercholesterolemic Diets.

The effects of palm oil, soybean oil, and perilla oil on the lipid profiles of liver and serum were compared in young (1 month old) and adult (8 months old) rats fed on hypercholesterolemic diets. In young rats, the concentration of serum cholesterol was highest in the order of palm oil (PAO), soybean oil (SBO), and perilla oil (PEO), whereas it was comparable among the groups of adult rats, resulting in an age-dependent increase in the rats fed on PEO. In young rats, but not in adult rats, the ratio of HDL-/total-cholesterol was significantly increased with an increase in the degree of unsaturation of dietary fats. Dietary PAO, when compared with SBO or PEO, prevented the accumulation of liver cholesterol in adult rats, when expressed as mg per liver. No fat-effect on liver cholesterol was seen in young rats. SBO amd PEO, when compared with PAO, markedly enhanced fecal output of bile acids in adult rats. The concentration of serum triacylglycerol showed a fat-dependent response, whereas that of liver triacylglycerol showed both an ageand fat-dependent response. Thus, PAO showed an effect similar to that of SBO on the serum cholesterol level in adult animals fed on a hypercholesterolemic diet.