Effects of trans fatty acid (tFA)‐free fat formulations on lipid and lipoprotein metabolism in gerbils and hamsters

Abstract

The adverse health effects of dietary tFA resulting from the partial hydrogenation of liquid vegetable oils (PHVO) have prompted health agencies to advocate their reduction or complete elimination from the food supply. Alternatives to PHVO are being considered, including genetically modified oils with reduced PUFA, interesterified fats high in stearic acid, and naturally occurring oil blends with increased SFA. In the current study, we evaluated various oil blends‐ soybean oil (SO), low‐linoleic SO, interesterified SO, coconut oil, a vegetable‐oil blend (palm, corn & sunflower) and a palm oil fraction with an increased content of oleic acid for their effects on lipid and lipoprotein metabolism. In all, 96 male Mongolian gerbils and 75 male Golden Syrian hamsters were fed purified diets for 4 weeks containing ~ 30% calories from the test fat blends and ~0.1% w/w cholesterol. Plasma lipids, lipoprotein concentrations, composition, and particle sizes, and liver free and esterified cholesterol were measured. Despite minor differences between individual diets, only the coconut oil‐based diet (99% coconut oil, 1% SO) induced hypercholesterolemia in both species. These data suggest that within the context of currently recommended prudent diets, various tFA‐free fat formulations can be utilized without compromising plasma lipids. Whether the same occurs in humans is under investigation.