Changes in fatty liver index after consuming a Mediterranean diet: 6-year follow-up of the PREDIMED-Malaga trial.

OBJECTIVE: To analyze the effect of an intervention with a Mediterranean diet supplemented with either extra virgin olive oil or nuts, on the fatty liver index (FLI), compared to a low-fat control diet.

METHODS: Participants of the PREDIMED-Malaga trial, free from cardiovascular disease at baseline, but with a high risk to develop it, were included in this study. Anthropometric measurements were assessed and blood samples were taken to calculate participants' FLI at study baseline and after one, 3, 5 and 6 years. Mixed linear models were used to explore the fixed effects of the 3 intervention groups on the FLI as well as their interaction with time.

RESULTS: A total of 276 participants were included in the study. Average participant age was 67 years, with 66% of participants being women. The baseline prevalence of NAFL was 57%. The change in the FLI of the control group increased significantly over time (1.13±0.41; P=.006). In the MedDiet+EVOO group, the time trend of the change in the FLI was similar to that of the control group, although it was seen to be lower (-3.90±1.9; P=.038). In the MedDiet+Nuts group, the trend was significantly lower than that of the control group (-1.63±0.62; P=.009). In the MedDiet+Nuts group, the trend of changes in participants' BMI was 0.100 points lower per year compared to the control group (P=.004). In the control group, the change in waist circumference increased significantly over time (0.61±0.16cm/year; P<.001) in contrast to the MedDiet+EVOO group, in which this variable remained stable (-0.51±0.22; P=.019).

CONCLUSIONS: A dietary intervention consisting of a Mediterranean diet could delay or slow down the natural progression of NAFL, thus, being beneficial for its prevention and treatment. However, further studies supporting these conclusions have yet to be carried out.