OPTIMUM RATIO OF SATURATED TO MONO-UNSATURATED FATTY ACIDS IN RAT DIETS

Abstract

Fat mixtures were prepared in which the content of linoleic acid was held constant at approximately 10% of the total fatty acids, but the ratio of saturated to mono-unsaturated acids was varied from 3.51 to 1:8. These mixtures were added to a low-fat fox chow diet at the rate of 20 parts fat to 80 parts fox chow and the resulting mixtures were fed to weanling rats in 1 experiment and to semiadult rats in another. The feeding period was 9 weeks. In both experiments the male rats showed significant differences in final weight between the diets. Best weight gains were made on the fat mixture in which the fatty acid ratio was close to that of normal rat depot fat, viz. 1 part of saturated acid to 2 parts of mono-unsaturated acid. Female rats did not show significant differences in weight gain on the various fat mixtures. Excretion of lipid in the feces showed a tendency to increase with increasing ratios of unsaturated to saturated fatty acids in the diet.