[Dynamic study of the changes in the composition of fatty acids in serum lipid fractions under a diet rich in polyunsaturated fatty acids].

Appropriate adjustment of diet and specially reduction of the saturated fatty acids content is the cornerstone of correcting many hyperlipidemias. What we have tried in our study was first to show the evolution of the changes in the serum's fatty acids composition under a rich polyunsaturated fatty acids diet, second to find an index proving that the diet had correctly been taken. Chromatographic analysis were performed after ultracentrifugal separation of the lipoprotein fractions. Seven volunteers, non fat, and normolipemics were selected. Samples were collected every three or five days before and during the diet. The whole test lasted twenty days. What had been shown is that the linoleic acid content increased but the one of the oleic acid decreased in all lipoprotein fractions. Those changes are bestly illustrated by using the (formula: see text) ratio as a kinetic index. The triglycerid fraction modifications are faster than the phospholipid's one. Concerning the other fatty acids, the modifications are less spectacular : the palmitic acid decrease in every lipids fractions and the palmitoleic acid has a significant decrease only in the esterified cholesterol. And the stearic acid has no variation at least significatively.