Serum lipids in rats fed diets containing rice bran oil or high-linoleic acid safflower oil

Growing male Sprague-Dawley rats were fed purified diets containing 1% cholesterol, 0.15% cholic acid, and 10% of either rice bran oil (RBO) or high-linoleic acid safflower oil (HLSO), with nine rats being fed each diet. Food intake, growth, and serum cholesterol level were unaffected by the source of dietary oil; however, the serum levels of triglycerides and phospholipids were significantly (P<0.05) higher in animals fed RBO than in those fed HLSO. There were differences in the serum fatty acid pattern between the two groups-for instance, rats fed RBO had significantly higher levels (expressed as mol%) of total serum fatty acids as oleic acid, alpha-linolenic acid, and docosahexaenoic acid (DHA) than those fed HLSO, but a lower level of linoleic acid. Many of the differences in lipid status between the two groups were attributed to compositional differences between the oils, which included RBO's having higher levels of oleic acid and alpha-linolenic acid (the precursor of DHA) than HLSO, but a lower level of linoleic acid. The higher serum level of DHA in animals fed RBO indicates that this oil may have an important advantage over HLSO with regard to the development of brain and retinal tissue.