Bottomline: Linoleic acid, the polyunsaturated fat found commonly in vegetable oils, may injure the arteries by turning on a destructive gene that triggers clogged arteries.Diabetes.2005.May;54(5):1506-13.

Summary: Earlier research (Blankenhorn, Toborek) has shown that linoleic acid can selectively trigger a pro-inflammatory environment in blood vessels and is associated with the appearance of new atherosclerotic lesions in coronary arteries.  This study shows a new mechanism by which linoleic acid may damage arteries--by turning on the gene that increases the uptake of a potent oxidated-LDL, which is more destructive to blood vessels than regular LDL.

Study Quote:  "Of all the fatty acids, linoleic acid appears to be the one with the most profound and deleterious effects on endothelial barrier function"

Comment:This study adds to a growing evidence that links the omega-6 fatty acid, linoleic acid, to heart disease (see Linoleic Acid Hurts Heart--Cardiac Inflammation, Eating Omega-6 Fat Hurts the Heart—Framingham Heart Study, Clogged Arteries--Increased Risk with Dietary Omega-6 Fat).  Ironically, linoleic acid is a polyunsaturated fat that has been widely promoted as "heart healthy" and is commonly found in margarine, mayonnaise, salad dressings, fast foods and processed foods.

Links to Studies:
Blankenhorn D et al.
The influence of diet on the appearance of new lesions in human coronary arteries JAMA 1990 263: 1646-1652. (Abstract)

Fritz Maingrette and Geneviève Renier.
Linoleic Acid Increases Lectin-Like Oxidized LDL Receptor-1 (LOX-1) Expression in Human Aortic Endothelial Cells Diabetes. 2005 (May) 54:1506-1513 (Free Full Text).

Toborek M et al.
Unsaturated fatty acids selectively induce an inflammatory environment in human endothelial cells Am J Clin Nutr 2002 75: 119-125(Full Text)Am J Clin Nutr 2002 75: 119-125(Full Text)