Intravenous lipid emulsions (ILE) have demonstrated advantages including prevention of essential fatty acid (EFA) deficiency; however, too much EFA can down regulate fatty acid elongation leading to an imbalance of nutritional compounds in plasma and cell membranes. An olive oil-based ILE containing long-chain triacylglycerols (LCT) with a low content (20 %) of PUFA was administered for home parenteral nutrition (HPN) and compared with a conventional soyabean oil-based ILE (PUFA content, 60 %). Thirteen patients (26–92 years) with stable intestinal failure were randomised after a 1-month run-in period with a medium-chain triacylglycerols–LCT-based ILE, to receive 3 months of HPN with either olive oil- (n 6) or soyabean oil-based (n 7) ILE. The nutritional impact and safety of HPN, oral intakes and absorption rates, phospholipid fatty acids in plasma and lymphocyte cell membrane were assessed. The only clinical event reported was one case of pneumonia (soya group). In both groups, 20 : 3n-9:20:4n-6 ratios remained within normal ranges (0·03–0·07). There was a significant increase of γ-linolenic acid (γ-LA) in plasma and lymphocyte cell membrane (P=0·02) and of oleic acid in plasma (P<0·01) in the olive compared with the soya group. A significant correlation was found between γ-LA (day 90 – day 0) in plasma and PUFA parenteral intakes (P=0·02), but neither with fat intakes nor with fat absorption rates. In conclusion, plasma and lymphocyte EFA pattern remained in normal ranges without EFA deficiency with both lipid emulsions, despite a lower content of n-3 and n-6 series with the olive oil-based ILE.