Alterations in the Fatty Acid Composition of Human Lymph and Serum Lipoproteins by Single Feedings.

Dole and co-workers ( 1 ) reported that the fatty acid composition of serum chylomicrons and other serum lipid classes was remarkably stable despite the feeding of fats of widely different composition. Blomstrand and Dahlbach (2) analyzed the fatty acid composition of human thoracic duct chyle in two subjects after the feeding of fat formulas and observed that lymph triglycerides closely resembled the pattern of the dietary fat. Cholesterol esters of the chyle were also found to be markedly influenced by the dietary fat, but the FFA and phospholipids were relatively unaffected. Fernandes, van de Kamer, and Weijers (3) studied the pattern of fatty acids in the chyle of a child with chylothorax and observed significant differences between the composition of the fed fat and that of the chylous fluid. Bragdon and Karmen (4) noted that the fatty acid composition of lymph and serum chylomicrons in the rat reflected dietary feeding to a marked extent, and reported that serum chylomicrons in humans also changed to reflect the ingested lipid. In this study, the acute effect of single feeding of fats on the composition of human thoracic duct lymph and serum has been studied. The thoracic duct chyle and serum were fractionated into 5 lipoprotein classes, and the fatty acid compositions of the lipids were analyzed to study the process of fat absorption and the extent of alterations in lipoprotein composition that occur after feeding of fats of different composition.