Early mortality effect of partially hydrogenated vegetable oils in stroke-prone spontaneously hypertensive rats (SHRSP)

Partially hydrogenated vegetable oils have been suspected to have potential adverse health effects but no definitive conclusions about their safety have been reached. Instead, beneficial effects have been reported in animal experiments (e.g., hypotensive, anti-atherogenic and anti-thrombotic activities of hydrogenated corn oil as compared with olive oil in stroke- prone spontaneously hypertensive rats (SHRSP)). However, we have found that both partially hydrogenated rapeseed and soybean oils (10% w/w of diet) as well as rapeseed oil have shortened the survival time of SHRSP rats by 40% as compared with soybean oil. Soybean oil and partially hydrogenated soybean oil affected the fatty acid profiles of plasma and aortic lipids but no significant differences were observed in the contents of total cholesterol or phospholipids of these tissues nor were there any differences in blood pressures. Tissue lipids contained comparable amounts of linoleic and arachidonic acids and no symptoms of essential fatty acid-deficiency were apparent in SHRSP rat fed the hydrogenated oils. It is suggested that the survival time-shortening activity of partially hydrogenated soybean oil was exerted by the cis and trans isomers of octadecenoate and/or by an unidentified factor(s) generated during partial hydrogenation.