Effect of ω3 fatty acid on plasma lipids, cholesterol and lipoprotein fatty acid content in NIDDM patients

Abstract

This study was conducted to examine the effect of ω3 fatty acid supplementation on plasma lipid, cholesterol and lipoprotein fatty acid content of non-insulin-dependent diabetic individuals consuming a higher (0.65, n = 10) or lower (0.44, n = 18) ratio of dietary polyunsaturated to saturated fatty acid (P/S). The participants were initially given an olive oil supplement (placebo) equivalent to 35 mg of 18:1 · kg body weight-1 · day-1 for 3 months. This was followed by two ω3 supplement periods in a randomized crossover. In these 3-month periods, participants were given a linseed oil supplement equivalent to 35 mg of 18:3ω3 · kg body weight-1 · day-1 or a fish oil supplement equivalent to 35 mg of 20:5ω3 + 22:6ω3 · kg body weight-1 · day-1. At the end of each supplement period, a blood sample was drawn from each participant for lipid, lipoprotein, insulin, glucagon and C-peptide analyses. At the end of each 3-month period a 7-day dietary record was completed to calculate dietary fat intake and P/S ratio. Results indicate that fish oil significantly reduced plasma triacylglycerol level (p < 0.05) and increased 20:5ω3 and 22:6ω3 content of all lipoprotein lipid classes. Linolenic acid supplementation had no effect on plasma triacylglycerol level, but it increased 18:3ω3 content of lipoprotein cholesterol ester fractions (p < 0.05). A slight increase in 20:5ω3, but not 22:6ω3, content was noted in lipoprotein lipid classes as a result of 18:3ω3 supplementation. LDL and HDL cholesterol, insulin, glucagon and C-peptide levels were not affected by either ω3 supplement. It is concluded that a modest intake of ω3 fatty acids, such as could be obtained from consuming fish regularly, will reduce plasma triglyceride level without affecting LDL or HDL cholesterol levels.