Adherence to a Mediterranean diet may improve serum adiponectin in adults with nonalcoholic fatty liver disease: The MEDINA randomized controlled trial.

Nonalcoholic fatty liver disease (NAFLD) affects approximately 30% of adults worldwide, with chronic low-grade inflammation being a key pathophysiological feature of progression. The Mediterranean diet (MedDiet) is recognized for improving metabolic and hepatic outcomes in people with diabetes and NAFLD, in part, via anti-inflammatory properties. The aim of this study was to determine the effect of an ad libitum MedDiet versus low-fat diet (LFD) on inflammatory markers in adults with NAFLD. It was hypothesized that the MedDiet, and its individual components, would improve inflammation. This multicenter, randomized controlled trial, randomized participants to a MedDiet or LFD intervention for 12 weeks. Primary outcomes included change from baseline to 12 weeks for serum high-sensitivity C-reactive protein, interleukin-6, tumor necrosis factor-α, adiponectin, leptin, and resistin. Forty-two participants (60% female; age 52.3 ± 12.6 years; body mass index, 32.2 ± 6.2 kg/m²) were randomized to the MedDiet (n = 19) or low-fat diet (n = 23). At 12 weeks, the LFD showed a greater decrease in leptin compared with the MedDiet (-1.20 ± 3.9 ng/mL vs 0.64 ± 3.5 ng/mL, P = .010). Adiponectin significantly improved within the MedDiet (13.7 ± 9.2 µg/mL to 17.0 ± 12.5 µg/mL, P = .016), but not within the LFD group. No statistically significant changes were observed for other inflammatory markers following the MedDiet or LFD. Adherence to the MedDiet significantly improved in both study arms, although greater improvements were seen in the MedDiet group. Adiponectin significantly improved following a Mediterranean diet intervention, in the absence of weight loss. The low-fat diet did not elicit improvements in inflammatory markers. High-quality clinical trials appropriately powered to inflammatory markers are required in this population.

Effect of Dietary Intervention, with or without Cointerventions, on Inflammatory Markers in Patients with Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis.

Nonalcoholic fatty liver disease (NAFLD) encompasses a spectrum of disease from simple steatosis to nonalcoholic steatohepatitis, with inflammatory cytokines and adipokines identified as drivers of disease progression. Poor dietary patterns are known to promote an inflammatory milieu, although the effects of specific diets remain largely unknown. This review aimed to gather and summarize new and existing evidence on the effect of dietary intervention on inflammatory markers in patients with NAFLD. The electronic databases MEDLINE, EMBASE, CINAHL, and Cochrane were searched for clinical trials which investigated outcomes of inflammatory cytokines and adipokines. Eligible studies included adults >18 y with NAFLD, which compared a dietary intervention with an alternative diet or control (no intervention) group or were accompanied by supplementation or other lifestyle interventions. Outcomes for inflammatory markers were grouped and pooled for meta-analysis where heterogeneity was allowed. Methodological quality and risk of bias were assessed using the Academy of Nutrition and Dietetics Criteria. Overall, 44 studies with a total of 2579 participants were included. Meta-analyses indicated intervention with an isocaloric diet plus supplement was more effective in reducing C-reactive protein (CRP) [standard mean difference (SMD): 0.44; 95% CI: 0.20, 0.68; P = 0.0003] and tumor necrosis factor-alpha (TNF-α) (SMD: 0.74; 95% CI: 0.02, 1.46; P = 0.03) than an isocaloric diet alone. No significant weighting was shown between a hypocaloric diet with or without supplementation for CRP (SMD: 0.30; 95% CI: -0.84, 1.44; P = 0.60) and TNF-α (SMD: 0.01; 95% CI: -0.43, 0.45; P = 0.97). In conclusion, hypocaloric and energy-restricted diets alone or with supplementation, and isocaloric diets with supplementation were shown to be most effective in improving the inflammatory profile of patients with NAFLD. To better determine the effectiveness of dietary intervention alone on a NAFLD population, further investigations of longer durations, with larger sample sizes are required.

Effect of dietary intervention, with or without co-interventions, on inflammatory markers in patients with nonalcoholic fatty liver disease: a systematic literature review.

CONTEXT: Nonalcoholic fatty liver disease (NAFLD) represents a spectrum of liver disorders, ranging from simple steatosis to nonalcoholic steatohepatitis (NASH), with inflammation acting as a key driver in its pathogenesis and progression. Diet has the potential to mediate the release of inflammatory markers; however, little is known about the effects of various diets. OBJECTIVE: This systematic review aimed to evaluate the effect of dietary interventions on cytokines and adipokines in patients with NAFLD. DATA SOURCES: The electronic databases MEDLINE, EMBASE, CINAHL, and Cochrane Library were searched for clinical trials investigating dietary interventions, with or without supplementation, on cytokines and adipokines in NAFLD patients. DATA EXTRACTION: Basic characteristics of populations, dietary intervention protocol, cytokines, and adipokines were extracted for each study. Quality of evidence was assessed using the American Dietetic Association criteria. DATA ANALYSIS: Nineteen studies with a total of 874 participants were included. The most frequently reported inflammatory outcomes were C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), adiponectin, and leptin. Hypocaloric, isocaloric, or low-fat diets significantly (P < 0.05) lowered levels of CRP, TNF-α, and adiponectin. The addition of nutraceutical or pharmacological supplementation to dietary interventions appeared to elicit additional benefits for all of the most frequently reported inflammatory markers. CONCLUSIONS: Hypo- or isocaloric diets alone, or with co-interventions that included a nutraceutical or pharmacological supplementation, appear to improve the inflammatory profile in patients with NAFLD. Thus, anti-inflammatory diets may have the potential to improve underlying chronic inflammation that underpins the pathophysiological mechanisms of NAFLD. In the absence of any known liver-sensitive markers, the use of cytokines and adipokines as a surrogate marker of liver disease should be further investigated in well-controlled trials.

The effect of high-polyphenol extra virgin olive oil on cardiovascular risk factors: A systematic review and meta-analysis.

The polyphenol fraction of extra-virgin olive oil may be partly responsible for its cardioprotective effects. The aim of this systematic review and meta-analysis was to evaluate the effect of high versus low polyphenol olive oil on cardiovascular disease (CVD) risk factors in clinical trials. In accordance with PRISMA guidelines, CINAHL, PubMed, Embase and Cochrane databases were systematically searched for relevant studies. Randomized controlled trials that investigated markers of CVD risk (e.g. outcomes related to cholesterol, inflammation, oxidative stress) were included. Risk of bias was assessed using the Jadad scale. A meta-analysis was conducted using clinical trial data with available CVD risk outcomes. Twenty-six studies were included. Compared to low polyphenol olive oil, high polyphenol olive oil significantly improved measures of malondialdehyde (MD: -0.07µmol/L [95%CI: -0.12, -0.02µmol/L]; I2: 88%; p = 0.004), oxidized LDL (SMD: -0.44 [95%CI: -0.78, -0.10µmol/L]; I2: 41%; P = 0.01), total cholesterol (MD 4.5 mg/dL [95%CI: -6.54, -2.39 mg/dL]; p<0.0001) and HDL cholesterol (MD 2.37 mg/dL [95%CI: 0.41, 5.04 mg/dL]; p = 0.02). Subgroup analyses and individual studies reported additional improvements in inflammatory markers and blood pressure. Most studies were rated as having low-to-moderate risk of bias. High polyphenol oils confer some CVD-risk reduction benefits; however, further studies with longer duration and in non-Mediterranean populations are required.

Non-alcoholic fatty liver disease patients attending two metropolitan hospitals in Melbourne, Australia: high risk status and low prevalence.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease globally, with increased rates in high-risk populations, including type 2 diabetes and obesity. The condition increases the risk of end-stage liver disease, hepatocellular carcinoma and all-cause mortality. NAFLD is asymptomatic and often remains undiagnosed as routine screening in high-risk groups is not practised. AIMS: The aim of this study was to determine the rates and characteristics of NAFLD patients attending liver clinics at two Melbourne metropolitan hospitals. METHODS: Liver clinics were prospectively screened for 10 consecutive months and participants with a diagnosis of NAFLD were further evaluated using pathology and imaging results obtained from medical records. RESULTS: Of the 2050 patients screened, 148 (7%) had NAFLD predominantly diagnosed using ultrasound (81%). NAFLD patients were obese (mean body mass index 30.7 ± 5.9 kg/m2 ), insulin resistant (median HOMA 4.2 (3.2) mmol/L) and had elevated liver enzymes (ALT median, males 47.0 (34.3), females 36.0 (28.0) U/L), and 18% of patients had liver stiffness measuring >12 kPa, suggesting a moderate probability of cirrhosis. Patients with liver stiffness measuring ≥9.6 kPa had significantly higher: glucose (median 5.5 (1.2) vs 6.2 (5.3) mmol/L, P = 0.007), aspartate aminotransferase levels (median 25.5 (26.0) vs 41.0 (62.0) u/L, P = 0.0005) and HOMA (3.1 (3.0) vs 5.4 (5.5) mmol/L, P = 0.040). CONCLUSIONS: NAFLD constituted a minority of liver clinic patients, most of who were obese, insulin resistant and hypertensive, and many had an elevated liver stiffness measurement. NAFLD poses added adverse health outcomes to high-risk patients, and therefore, early detection is warranted.