Effect of Intake of Extra Virgin Olive Oil on Mortality in a South Italian Cohort with and without NAFLD

Abstract

Background: Extra-virgin olive oil (EVOO) is the main source of seasoning fat in the Mediterranean diet and it is one of the components with known protective factors on chronic-degenerative disease. We aimed to evaluate the effect of a medium-high level of oil consumption on mortality in a cohort with good adherence to the Mediterranean diet. Methods: A total of 2754 subjects who had completed the food questionnaire in the Multicenter Italian study on Cholelithiasis (MICOL) cohort were included in the study. EVOO consumption was categorized in four levels (<20 g/die, 21–30 g/die, 31–40 g/die, >40 g/die). We performed a flexible parametric survival model to assess mortality by EVOO consumption level adjusted for some covariates. We also performed the analysis on subjects with and without non-alcoholic fatty liver disease (NAFLD) to evaluate the effects of oil in this more fragile sub-cohort. Results: We found a statistically significant negative effect on mortality for the whole sample when EVOO consumption was used, both as a continuous variable and when categorized. The protective effect was stronger in the sub-cohort with NAFLD, especially for the highest levels of EVOO consumption (HR = 0.58 with p < 0.05). Conclusions: Our study has shown a protective effect of EVOO consumption towards all causes of mortality. Despite the higher caloric intake, the protective power is greater for a consumption >40 g/day in both the overall cohort and the sub-cohorts with and without NAFLD.

Development and Internal Validation of a Model for Predicting Overall Survival in Subjects with MAFLD: A Cohort Study

“…Our hypothesis is supported by the literature, and more specifically by the multiple papers that show the benefits of the Mediterranean diet in helping to prevent metabolic diseases, cancers, and cardiovascular disease [30,31], including a recent study that showed the protective effect of extra virgin olive oil on overall mortality and NAFLD [32].…”

Olive oil intake and cardiovascular disease, cancer, and all-cause mortality: a systematic review and dose–response meta-analysis of prospective cohort studies

“…Table S3† shows the characteristics of the chosen articles. Of these, 24 were from Europe, 10,11,13,20,21,36–54 4 from North America, 9,12,18,19 1 from Asia, 14 and 1 covering 13 countries. 35 The sample size ranged from 673 39 to 547 183.…”

“…The study contained 14 studies (13 articles) 9,11,13,14,18,20,21,38–40,47,53,54 with 176 729 cases of all-cause mortality among 723 224 individuals. The combined RR for the categories with the highest and lowest intakes of olive oil was 0.85 (95% CI: 0.81, 0.89), with some heterogeneity ( I 2 = 88.4%, P heterogeneity < 0.001; Fig.…”

“…Nine studies (8 articles) 9,11,13,18,40,47,52,54 qualified for dose–response analysis. An inverse correlation was seen between per 10 g d −1 increment of olive oil and all-cause mortality (RR: 0.92; 95% CI: 0.90, 0.94; I 2 = 36.1%, P heterogeneity = 0.129; Fig.…”

Is the Mediterranean diet a good preventive measure for NASH?

“…Finally, it emerged that in the NASH group, the gene expression of the fibrotic markers tumor growth factor(TGF)-β and α-SMA was significantly increased, while the NASH+RA group showed a significant reduction in the gene expression of TGF-β and α-SMA (P < 0.05). Komeili-Movahhed et al carried out a new study on 24 C57/BL6 mice treated for 8 weeks [63] . During the experiment, the mice were divided into four groups: CO group (standard diet), RA group (standard diet and RA (10 mg/kg), NASH group (MCD diet), and NASH+ RA group (MCD + RA diet (10 mg/kg).…”