Absorption of safflower oil and structured lipid preparations in patients with cystic fibrosis

Abstract Patients with cystic fibrosis (CF) and pancreatic insufficiency usually have decreased linoleic and increased oleic, palmitoleic and eicosatrienoic (20∶3ω9) acids compared to normal values of blood and tissue lipids. These changes are consistent with early essential fatty acid deficiency and are observed despite the regular use of exogenous pancreatic enzyme supplementation. As part of a study to determine the relative role of malabsorption as the etiology for the altered fatty acid status, the change in total plasma fatty acids and in area percent of plasma linoleic acid was determined in CF patients and control subjects following the ingestion of various lipid supplements, including two safflower oil preparations and two structured lipid preparations. Fasting subjects consumed 33 g of lipid in a milkshake containing 15 g of protein and 45 g of carbohydrate. Plasma samples obtained 0, 2, 4, 6 and 8 hr after the meal showed that the CF patients absorbed all preparations when administered with their regular dose of pancreatic enzyme supplement. Comparison of the patterns of increase for total plasma fatty acids and area percent of plasma linoleic acid following the administration of the different lipid supplements in CF patients and control subjects suggests that(a) malabsorption alone is not the cause of the abnormal fatty acid composition in the lipids of CF patients and that increased caloric intake along with consumption of adequate amounts of linoleic acid should improve the linoleic acid status of CF patients; (b) there may be selectively increased metabolism of certain fatty acids from the ingested lipids in the relatively malnourished CF patient compared to control subjects; and (c) conditions favoring the persistence of nonpancreatic lipases seem also to favor absorption and utilization of the structured lipid preparation containing medium chain length fatty acids and linoleic acid in CF patients compared to control subjects.