Naoto Kudo

Serum Retinol, α-Tocopherol, and β-Carotene Levels Are Not Altered by Excess Ingestion of Diacylglycerol-Containing Plant Sterol Esters

Background: Diacylglycerol (DAG) suppresses the postprandial increase in serum triglycerides, and has antiobesity effects. On the other hand, plant sterol esters (PSE) lower serum cholesterol levels in hypercholesterolemia. Thus, DAG-containing PSE (PSE/DAG) would be expected to maintain an appropriate serum cholesterol level and decrease the risk of arteriosclerotic disorders. Several recent studies, however, report negative effects of PSE on serum fat-soluble (pro)vitamin levels. The objective of this study was to investigate the effect of PSE/DAG on serum retinol, β-carotene, and α-tocopherol levels using a threefold excess of the effective dose obtained in our previous study. Methods: A randomized placebo-controlled double-blind parallel study was performed in healthy and mildly hypercholesterolemic subjects, in which the subjects ingested 1.2 g PSE/30 g DAG for 2 weeks in the form of mayonnaise-type products. Triacylglycerol (TAG) mayonnaise was used as a control. Result: There were no subjective adverse effects or changes in serum retinol, α-tocopherol, and β-carotene levels, abdominal symptoms, hematologic values, or blood biochemical values. Conclusion: Ingestion of a threefold excess of PSE/DAG for 2 weeks had no adverse effects compared to ingestion of conventional TAG mayonnaise.