Abstract

The metabolism of alpha-linolenic acid from canola oil was studied in eight normolipidemic men. The 42-day study was divided into three periods: a 6-day pre-experimental and two 18-day experimental. Approximately 75% of the dietary fat (28% of total energy) was provided by a mixture of fats during the pre-experimental period and either canola oil (CO) or sunflower oil (SO) during the experimental periods. The CO and SO diets were fed in a cross-over design. The ratios of linoleic to linolenic acid were 2.6:1 and 73.9:1 in the CO and SO diets, respectively. Dietary fat source had an effect on plasma phospholipid fatty acids: 18:1n-9, 18:3n-3 and 20:5n-3 were higher (p less than 0.05), and 18:2n-6 was lower in the phosphatidylcholine fraction; 18:1n-9 was higher and 20:4n-6 lower in the phosphatidyl-ethanolamine fraction; and 18:1n-9 and 20:5n-3 were higher and 20:4n-6 and 22:6n-3 were lower in the alkenylacyl ethanolamine phospholipid fraction on the CO diet as compared to the SO diet. Consumption of the canola oil diet resulted in higher n-3 fatty acid levels and lower n-6 fatty acid levels in plasma phospholipids than consumption of the sunflower oil diet.