The effects of dietary supplementation with inulin and inulin-propionate ester on hepatic steatosis in adults with non-alcoholic fatty liver disease.

Plain Language Summary

Non-alcoholic fatty liver disease (NAFLD) is characterised by an accumulation of fat within the liver, and is strongly associated with obesity. Recent investigations suggest that diet, the gut microbiota and liver fat storage could be linked through a mechanism involving short chain fatty acids (SCFA), in particular the SCFA propionate, which are produced by the gut bacteria. The aim of this randomised controlled study was to evaluate whether an inulin-propionate ester (IPE) has benefits in patients with NAFLD. Subjects with NAFLD received either 20 g/d of inulin (control) or IPE for 42 days. 18 subjects completed the trial. Intrahepatocellular lipids IHCL (a marker of fat accumulation in the liver) increased post supplementation in both groups with no significant difference between control and IPE group. There was a change in insulin resistance (HOMA-IR) which was significantly different between groups, with a non-significant increase in the inulin-control group and decrease in the IPE group. There were no within- or between-group differences in body composition. The authors discuss these unexpected results and suggest that the SCFA acetate, from inulin fermentation by gut bacteria, may have led to an increase in IHCL which was attenuated by the propionate.