Nutritional assessment and hepatic fatty acid composition in non-alcoholic fatty liver disease (NAFLD): a cross-sectional study

Abstract

Background/aims: Low hepatic n-6 and n-3 polyunsaturated fatty acid (PUFA) may contribute to steatosis and steatohepatitis and can be affected by diet and oxidative stress.

Methods: Seventy-three patients referred for elevated liver enzymes and suspected NAFLD were assessed. Nutritional assessment, hepatic FA composition and oxidative stress were compared between these groups: simple steatosis (SS, n=18), steatohepatitis (NASH, n=38) and minimal findings on liver biopsy (MF, n=17).

Results: Patients with NASH had higher: BMI, central obesity, body fat, insulin resistance, dyslipidemia and lower physical activity compared to the other groups. They also had relatively lower hepatic n-3 and n-6 PUFA, a decrease in the ratio of metabolites to essential FA precursors for both n-6 and n-3 FA (eicosapentaenoic+docosahexaenoic/linolenic and arachidonic/linoleic acid ratios) and higher liver lipid peroxides with lower antioxidant power, when compared to MF. Overall, there was no significant difference between SS and NASH in FA composition. Self-reported dietary intake and red blood cell FA composition were similar among the three groups.

Conclusions: NASH patients have more metabolic abnormalities. This is associated with higher oxidative stress and lower n-3 and n-6 PUFA in the liver in the absence of any differences in dietary FA composition.