Effects of a 1-year dietary intervention with n-3 polyunsaturated fatty acid-enriched olive oil on non-alcoholic fatty liver disease patients: a preliminary study

Background and aims Non-alcoholic fatty liver disease (NAFLD) is a worldwide diffuse condition due to alimentary, environment and genetic factors. The aim of our preliminary study was to evaluate the effectiveness of long-term consumption of food enriched with n-3 polyunsaturated fatty acids (PUFA) in patients with NAFLD. Methods Eleven patients were enrolled; six (four males, two females) were planned for oral administration of 6.5 ml olive oil enriched with n-3 PUFA for 12 months, while five (four males, one female) were used as controls. Results Consumption of olive oil enriched with n-3 PUFA demonstrated a significant improvement of liver echo-texture and of the Doppler Perfusion Index after 12 months (after: 0.19 +/- 0.02 vs. pre: 0.15 +/- 0.03; P < 0.05), whereas no significant changes were seen at the end of follow-up in controls. Moreover, patients who consumed the olive oil enriched with n-3 PUFA showed a significant amelioration of liver enzymes, and of triglycerides (post: 132.8 +/- 63.7 vs. pre: 164.5 +/- 85.5 mg/dl; P = 0.04) in a general linear model adjusted for age and gender. Interestingly, patients reported to have a significant increase of adiponectin levels (post: 1,487.9 +/- 96.7 vs. pre: 1,143 +/- 24.8 mu g/ml; P = 0.04). Conclusion The results of this preliminary study showed that long-term consumption of olive oil enriched with n-3 PUFA in patients with NAFLD is able to decrease circulating liver enzymes and triglycerides, with a significant improvement of adiponectin levels.