Invited Review: Selection of Optimal Lipid Sources in Enteral and Parenteral Nutrition

Abstract

The manipulation of dietary fat intake can affect the response to disease, injury, and infection. These effects include enhancement or inhibition of immune function, altered susceptibility to cardiovascular disease, promotion or maintenance of gut integrity, and prevention of total parenteral nutrition-induced hepatic dysfunction. These effects may occur as a result of changes in the fatty acid composition of biomembranes or changes in concentrations of lipid moieties such as prostaglandins or leukotrienes. Those fats that have been shown to affect physiologic function include long-chain, medium-chain, and short-chain fatty acids and ω-3 and ω-6 fatty acids. Currently available enteral and parenteral products used for nutrition support contain widely varied amounts of these different fatty acids. Therefore, the selection of the most appropriate product or nutrition support regimen for an individual patient requires an understanding of the metabolism of these different fat substrates, their therapeutic indications, and the contraindications and controversies that surround their use. This article reviews these issues and also focuses on several alternate lipid sources such as short-chain fatty acids, medium-chain fatty acids, ω-3 fatty acids, and blended and structured lipids.