Palmolein and groundnut oil have comparable effects on blood lipids and platelet aggregation in healthy Indian subjects

Abstract

Substitution of palmolein (POL) for groundnut oil (GNO) doubles saturated fatty acids and decreases by half the linoleic acid (18:2n-6) content of Indian diets. The effects of this substitution on selected parameters of cardiovascular risk and membrane functions were studied in middle-aged subjects. Both metabolic (short-term) and "in-home" (long-term) studies were conducted, and the subjects were crossed over from GNO to POL or vice versa. During both studies and in both sexes, blood pressure, plasma levels of total cholesterol and triglycerides and their distributions in various lipoprotein fractions were not altered. The lower 18:2n-6 and higher 16:0 intakes were reflected in fatty acid compositions of cholesteryl esters and triglycerides. However, the plasma and platelet phospholipid fatty acid patterns did not shift toward saturation. The observation that the levels of long-chain polyunsaturated fatty acids in phospholipids were similar at the end of GNO and POL regimens indicates that 18:2n-6 furnished during POL regimen may be sufficient to maintain the levels of arachidonic acid in cell membranes. Platelet aggregation, erythrocyte membrane fluidity, and activity of Na+, K+ ATPase, a membrane-bound enzyme, were essentially similar at the end of the two oil regimens. These results indicate that POL is comparable to GNO and may not induce hypercholesterolemia in Indian subjects consuming cereal-based diets containing 30% total fat calories and low cholesterol.