Palm olein increases plasma cholesterol moderately compared with olive oil in healthy individuals

Background: Despite the high content of palmitic acid, palm olein has been shown to have a neutral effect on plasma cholesterol concentrations when compared with olive oil, which is suggested to be attributable to palmitic acid in the sn-1 and sn-3 position. In contrast, palmitic acid is in the sn-2 position in lard. Objective: The objective was to investigate the effects of a diet rich in palm olein, fractionated palm oil, olive oil, and lard on plasma blood lipids, inflammatory markers, glucose, and insulin. Design: A controlled double-blinded, randomized 3 x 3 wk crossover dietary intervention study included 32 healthy men who daily replaced part of their habitual dietary fat intake with similar to 17% of energy from palm olein, olive oil, or lard, respectively. Results: Compared with intake of olive oil, palm olein and lard increased total cholesterol and LDL cholesterol (P < 0.0001). Palm olein resulted in a lower plasma triacylglycerol concentration than did olive oil (P < 0.01). No difference in effects was observed in plasma HDL-cholesterol, high-sensitivity C-reactive protein, plasminogen activator-1, insulin, and glucose concentrations. Conclusions: The current study did not support the previous finding that the effect of palm olein on total plasma cholesterol and LDL cholesterol in healthy individuals with normal plasma cholesterol concentrations is neutral compared with that of olive oil. Thus, sn-positioning was not confirmed to be important with regard to the effect on plasma cholesterol. The relatively lower plasma triacylglycerol concentration after the palm olein diet than after the olive oil diet was unexpected. This trial is registered at clinicaltrials. gov as NCT00743301. Am J Clin Nutr 2011; 94: 1426-32.