As evidence continues to mount indicating that inflammatory substances in the blood promote plaque growth, rupture clot formation and appear to predict the risk of heart attacks, as well as elevate LDL levels, serious questions are being raised about the benefits of so-called “good fats”. A single high-fat meal has been shown to impair blood flow in part because of acute damage to the inside “skin” of the arteries called the endothelium, which may explain why angina is often much worse for several hours after each high-fat meal. An important question is how dietary fats promote inflammation and cardiovascular disease. A study in the Journal of Lipid Research conducted at the University of Kentucky clearly demonstrated in an animal model that a high-fat diet promotes the absorption from the gut of lipopolysaccharides (LPS) which are part of bacterial cell membranes. LPS trigger immune cells to increase inflammation.1 This research demonstrated that a purified fat containing only oleic acid (olive oil is 78% oleic acid) resulted in a marked increase in LPS attached to chylomicrons in the blood compared to a short-chain fat containing only butyric acid. Neither protein nor carbohydrate triggers the production of chylomicrons. Only the long-chain fatty acids, which compose the vast majority of all naturally occurring fats and oils, increase the synthesis of these fat-rich lipoprotein particles. This may help explain the unique role of dietary fat in raising CRP and other inflammatory substances in the blood, which increasingly are linked to not only more cardiovascular disease, but also insulin resistance and type 2 diabetes.2 Bottom Line: This research shows dietary fat, including the so-called “good” ones, greatly increase both acute and chronic low-grade inflammation in the body perhaps by enhancing the transport of bacterial toxins (LPS) from the gut to the lymph system and bloodstream. Increased inflammation promotes insulin resistance and CVD. By James J. Kenney, PhD, RD, FACN 1. J Lipid Res 2009;50:90-7 2. Am J Clin Nutr 2007;86:1286-92
Stephanie Ronco has been editing in a professional capacity for the past 10 years. In addition to her work as an editor, Ronco has also served as a ghostwriter and writing tutor. A voracious reader, Ronco loves watching language evolve and change. When she’s not delving into her latest project, Ronco can be found teaching acting classes, performing in community theater, or sailing with her husband.