Associations between intakes of individual nutrients or whole food groups and non-alcoholic fatty liver disease among Korean adults

Dietary macro and micronutrients associated with MASLD: Analysis of a national US cohort database

INTRODUCTION AND OBJECTIVES

Our objective was to measure and compare the intake of macro and micronutrients in a cohort of individuals with Metabolic Syndrome Associated Steatotic Liver Disease (MASLD) compared with matched controls to identify areas of further research in this area; we identified nutrition-associated associations with MASLD in the United States general population.

MATERIALS AND METHODS

We used the 2017 - 2018 NHANES dataset. Elastography Controlled Attenuation Parameter (CAP score>280) in the absence of other liver disease was defined as MASLD in adults (>18). Advanced fibrosis was defined by transient elastography >10 kPa. Controls were adults without liver disease.

RESULTS

1648 MASLD cases (11.4 % advanced fibrosis) and 2527 controls were identified. MASLD cases were older (P<0.001), more likely males (P = 0.01), less likely to have a college education (P = 0.04) and more likely married (P = 0.002). MASLD cases were more likely to be of Mexican American or Hispanic ethnicity (P = 0.002), have higher BMI, and have higher prevalence of diabetes, hyperlipidemia and hypertension (P<0.001 for all). MASLD cases had higher hs-CRP (P = 0.02) and ferritin (P = 0.02). MASLD cases had lower total (P = 0.004) and added vitamin E in their diet (P = 0.002), lower vitamin K intake (P = 0.005), and higher selenium intake (P = 0.03). Caloric intake (P = 0.04), carbohydrate intake (P = 0.02), cholesterol intake (P = 0.03) and saturated fatty acid intake (P = 0.05) were higher in MASLD. Individuals with MASLD were more likely to be on a diet (P<0.001), sedentary (P = 0.008) and less likely to participate in moderate or vigorous recreational activities (P<0.001).

CONCLUSIONS

The deficiencies of micronutrients and excess of macronutrients point to oxidative stress, pro-inflammatory state, and lipotoxicity as pathways linking the US diet to MASLD. MASLD patients are more often on special diets, which may reflect prior provider counseling on diet changes to improve health.

Vitamin K2 protects mice against non-alcoholic fatty liver disease induced by high-fat diet

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide and there is a huge unmet need to find safer and more effective drugs. Vitamin K has been found to regulate lipid metabolism in the liver. However, the effects of vitamin K2 on NAFLD is unclear. This study aims to evaluate the preventive and therapeutic effects of vitamin K2 in the process of fatty liver formation and to explore molecular mechanisms the associated with lipid metabolism. A non-alcoholic fatty liver model was established by high-fat diet administration for three months. Vitamin K2 significantly reduced the body weight, abdominal circumference and body fat percentage of NAFLD mice. Vitamin K2 also showed histological benefits in reducing hepatic steatosis. NAFLD mice induced by high-fat diet showed increased HMGR while vitamin K2 intervention could reverse the pathological lterations. Adiponectin (APN) is an endogenous bioactive polypeptide or protein secreted by adipocytes. We detected APN, SOD, AlaDH and other indicators that may affect the state of high-fat diet mice, but the experimental results showed that the above indicators did not change significantly. It is worth noting that the effect of vitamin K2 supplementation on the lipid-lowering effect of uc OC in vivo needs to be further explored. This study first reported the protective effect of vitamin K2 on high-fat diet-induced NAFLD in mice. The protective effect of vitamin K2 may be related to the improvement of lipid metabolism disorder in NAFLD.

Dietary approaches to stop hypertension (DASH) diet improves hepatic fibrosis, steatosis and liver enzymes in patients with non-alcoholic fatty liver disease: a randomized controlled trial

PURPOSE

Recent evidence suggests that adherence to dietary approaches to stop hypertension (DASH) diet can be effective in managing non-alcoholic fatty liver disease (NAFLD). We investigated the effect of DASH diet on hepatic fibrosis, steatosis and liver enzymes in patients with NAFLD.

METHODS

This 12-week randomized controlled trial was conducted among seventy patients with NAFLD who were randomly assigned into two groups including intervention group (DASH diet containing 50-55% carbohydrate, 15-20% protein, and 30% total fat) and the control group (a healthy diet containing 50-55% carbohydrate, 15-20% protein, and 30% total fat). Both diets were calorie-restricted (500-700 kcal lower than the energy requirement). The primary outcomes included hepatic fibrosis, hepatic steatosis, alanine transaminase (ALT), aspartate transaminase (AST) and gamma-glutamyl transpeptidase (GGT).

RESULTS

At the baseline, there was no significant difference between two groups in the level of hepatic fibrosis (P = 0.63), hepatic steatosis (P = 0.53), ALT (P = 0.93), AST (P = 0.18) and GGT (P = 0.76). A significant reduction was found in the intervention group compared to the control group in hepatic fibrosis (23 grades reduction vs. 7 grades reduction; P = 0.008) and hepatic steatosis (31 grades reduction vs. 9 grades reduction; P = 0.03) after intervention. In addition, a significant change was observed in the intervention group compared to control group in ALT ( - 8.50 ± 8.98 vs.  - 2.09 ± 7.29; P = 0.002), and AST ( - 5.79 ± 6.83 vs.  - 0.51 ± 6.62; P = 0.002).

CONCLUSIONS

Adherence to DASH diet may be effective in management of NAFLD.

TRIAL REGISTRATION

The trial was registered on 06 February 2022 at Iranian Registry of Clinical Trials (IRCT20170117032026N3) with URL: https://www.irct.ir/trial/60887 .

Effects of Egg Consumption on Subjects with SLD or Hypertension: A MICOL Study

BACKGROUND

Steatotic liver disease (SLD) is defined as a fat accumulation in more than 5% of hepatocytes; it can progress to non-alcoholic steatohepatitis (NASH), associated with an increased state of inflammation. The aim of this study was to explore the protective effects of eating eggs and any association with SLD and hypertension (HTN).

METHODS

The study cohort included 908 participants assessed in the fourth recall of the MICOL study, grouped into four groups, based on NALFD and/or HTN.

RESULTS

The prevalence of HTN and SLD among participants was 31.61%. Overall, the results indicated a statistical significance of egg consumption, showing a protective role against the two disease conditions, in both the raw and adjusted models (RRR = 0.34, p = 0.009, 0.15 to 0.76 95% C.I.).

CONCLUSIONS

Many differences were found among the groups, and the protective role of eating eggs was amply demonstrated. We can conclude that it is unwise to demonize the intake of this food and its nutritional properties, in contrast with previous reports in the literature.

Fatty acid composition but not quantity is an important indicator of non-alcoholic fatty liver disease: a systematic review

BACKGROUND

There is still paucity on the effects of dietary and supplemental fatty acid on non-alcoholic fatty liver disease (NAFLD). The aim of this review is to systematically review and summarise the effect of fatty acids intake on liver-related outcomes in adult patients with NAFLD.

METHODS

The review was conducted using Cochrane CENTRAL Library, Scopus, Embase, MEDLINE, PubMed, and Web of Science. A total of 2786 records were identified, and of these, 36 studies (31 were randomised control trials (RCTs), and 5 were case-control studies) were included. Quality assessment was conducted using the Revised Cochrane Risk of Bias tool and Joanna Briggs Institute checklists.

RESULTS

Of 36 articles, 79% of RCTs and 66% of case-control studies had a low risk of bias. Potential heterogeneity has been observed in assessment of liver-related outcomes. According to the RCTs, there was moderate evidence (3/6 studies) that a diet characterised by a high MUFA, PUFA and low SFA showed reduced liver fat and stiffness. The using of culinary fats that are high in MUFA (4/6 studies) reduces liver steatosis. n-3 PUFA supplementation in combination with a hypocaloric or heart healthy diet with a low SFA improved liver enzyme level (5/14 studies) and steatosis score (3/14 studies).

CONCLUSIONS

Effects on NAFLD parameters, including liver fat content (assessed via magnetic resonance imaging/spectroscopy), stiffness and steatosis score (assessed by ultrasonography), were primarily related to fatty acid composition independent of energy intake. Further investigation is needed to determine the mechanism of specific fatty acid on the accumulation of liver fat.

Dairy product consumption and risk of non-alcoholic fatty liver disease: A systematic review and meta-analysis of observational studies

BACKGROUND AND AIMS

It is unclear whether regular consumption of dairy products is associated with the risk of developing non-alcoholic fatty liver disease (NAFLD). Thus, we conducted a systematic review followed by a meta-analysis of studies reporting on the association of dairy consumption with NAFLD risk.

METHODS AND RESULTS

We comprehensively searched PubMed, Web of Science, and Scopus for observational studies that evaluated the association between dairy intake and NAFLD likelihood that were published before September 1, 2022. The reported odds ratios (ORs) of fully adjusted models and their 95% confidence intervals (CIs) were pooled using a random-effects model for the meta-analysis. Out of 1206 articles retrieved, 11 observational studies, including 43,649 participants and 11,020 cases, were included. Pooled OR indicated a significant association between dairy intake and NAFLD (OR = 0.90; 95% CI: 0.83, 0.98; I² = 67.8%, n = 11). Pooled ORs revealed that milk (OR: 0.86; 95% CI: 0.78, 0.95; I² = 65.7%, n = 6), yogurt (OR: 0.88; 95% CI: 0.82; I² = 0.0%, n = 4), and high-fat dairy (OR: 0.38; 95% CI: 0.19, 0.75; I² = 0.0%, n = 5) consumption was inversely associated with NAFLD while cheese was not linked to NAFLD risk.

CONCLUSION

We observed that consumption of dairy products is linked to a reduced risk of developing NAFLD. Overall, the data in the source articles is of low to moderate quality; therefore, further observational studies are required to support the current findings (PROSPERO Reg. number: CRD42022319028).

Effect of Nut Consumption on Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

Although previous epidemiological studies have been conducted to investigate the relationship between nut consumption and the risk of nonalcoholic fatty liver disease (NAFLD), the evidence remains inconclusive and contentious. The aim of our study was to further conduct a meta-analysis of observational studies to explore the latest evidence of the influence of nut consumption on NAFLD. This meta-analysis included a comprehensive search of all articles published in the PubMed and Web of Science online databases as of April 2023. A total of 11 articles were included, comprising 2 prospective cohort studies, 3 cross-sectional studies, and 7 case-control studies, and a random effects model was used to evaluate the relationship between nuts and NAFLD. Results showed that the odds ratio (OR) of NAFLD was 0.90 (95% CI: 0.81-0.99, p < 0.001) when comparing the highest and lowest total nut intake, indicating a significant negative correlation. Furthermore, subgroup analysis revealed that the protective effect of nuts on NAFLD was more significant in females (OR = 0.88; 95% CI: 0.78-0.98, I² = 76.2%). In summary, our findings provide support for a protective relationship between nut intake and risk of NAFLD. Further exploration of the association between other dietary components and NAFLD is an important avenue for future research.

Non-pharmacological management options for MAFLD: a practical guide

Lifestyle changes should be the main basis for any treatment for metabolic dysfunction-associated fatty liver disease (MAFLD), aiming to increase energy expenditure, reduce energy intake and improve the quality of nutrients consumed. As it is a multifactorial disease, approaches such as physical exercise, a better dietary pattern, and possible pharmacological intervention are shown to be more efficient when used simultaneously to the detriment of their applications. The main treatment for MAFLD is a lifestyle change consisting of diet, activity, exercise, and weight loss. The variables for training prescription such as type of physical exercise (aerobic or strength training), the weekly frequency, and the intensity most indicated for the treatment of MAFLD remain uncertain, that is, the recommendations must be adapted to the clinical conditions comorbidities, and preferences of each subject in a way individual. This review addresses recent management options for MAFLD including diet, nutrients, gut microbiota, and physical exercise.

Nutraceutical approaches to non-alcoholic fatty liver disease (NAFLD): A position paper from the International Lipid Expert Panel (ILEP)

Non-Alcoholic Fatty Liver Disease (NAFLD) is a common condition affecting around 10-25% of the general adult population, 15% of children, and even > 50% of individuals who have type 2 diabetes mellitus. It is a major cause of liver-related morbidity, and cardiovascular (CV) mortality is a common cause of death. In addition to being the initial step of irreversible alterations of the liver parenchyma causing cirrhosis, about 1/6 of those who develop NASH are at risk also developing CV disease (CVD). More recently the acronym MAFLD (Metabolic Associated Fatty Liver Disease) has been preferred by many European and US specialists, providing a clearer message on the metabolic etiology of the disease. The suggestions for the management of NAFLD are like those recommended by guidelines for CVD prevention. In this context, the general approach is to prescribe physical activity and dietary changes the effect weight loss. Lifestyle change in the NAFLD patient has been supplemented in some by the use of nutraceuticals, but the evidence based for these remains uncertain. The aim of this Position Paper was to summarize the clinical evidence relating to the effect of nutraceuticals on NAFLD-related parameters. Our reading of the data is that whilst many nutraceuticals have been studied in relation to NAFLD, none have sufficient evidence to recommend their routine use; robust trials are required to appropriately address efficacy and safety.

Association between Dietary Fatty Acid Intake and Liver Steatosis and Fibrosis in a Sample of Mexican-Origin Hispanic Adults with Overweight or Obesity

Rates of non-alcoholic fatty liver disease (NAFLD) vary dramatically among Hispanic subpopulations, with Mexican-origin (MO) Hispanics experiencing a disproportionate burden. This study examined dietary fatty acid (FA) intake among overweight and obese MO Hispanic adults in the United States (US) and evaluated its association with liver steatosis and fibrosis. Participants (N = 285, MO Hispanic adults) completed 24-h dietary recalls to assess dietary FA exposure. Liver steatosis and fibrosis were estimated using transient elastography (FibroScan®). Multiple regression analysis tested relationships between FA intakes and liver steatosis or fibrosis, adjusting for age, sex, body mass index (BMI) and total energy. A total of 51% (n = 145) of participants were suspected to have NAFLD and 20% self-reported a type 2 diabetes diagnosis. No significant association was observed between Linoleic Acid and α-Linolenic Acid (LA:ALA) ratio, or omega-6 to omega-3 (n-6:n-3) ratio and liver steatosis. However, a one-point increase in the LA:ALA ratio resulted in a 1.01% increase in the liver fibrosis scores (95% CI: [1.00, 1.03]; p = 0.03), and a one-point increase in the n-6:n-3 ratio resulted in a 1.02% increase in liver fibrosis score (95% CI: [1.01, 1.03]; p = 0.01). Further research is needed to determine if modulation of FA intake could reduce NAFLD risk in this high-risk population.

The role of dietary factors in nonalcoholic fatty liver disease to hepatocellular carcinoma progression: A systematic review

BACKGROUND AND AIMS

Dietary factors play an important role in promoting nonalcoholic fatty liver disease (NAFLD)-related hepatocellular carcinoma (HCC) development through regulation of metabolism and inflammation. However, so far there was no evidence regarding how dietary factors may influence different disease outcomes in the NAFLD to HCC progression. Our study aimed to comprehensively evaluate the role of dietary factors on the risk of progression from NAFLD to HCC.

METHODS

A comprehensive literature research was conducted in PubMed, Web of Science and Embase databases to identify case-control and cohort studies published up to March 15, 2022 in English. We included studies investigating associations of food and beverage items (excluding alcohol), food groups, dietary patterns, and dietary habits with incidence risk of four main chronic liver diseases involved in the NAFLD-to-HCC progression (i.e., NAFLD, liver fibrosis, liver cirrhosis, and HCC). Three researchers independently performed the literature search, selected eligible articles, performed data abstraction and evaluated study quality. After evaluating adequacy and credibility of the associations reported for each dietary factor and each liver disease outcome, we summarized and evaluated the consistency of associations based on a priori determined criteria considering study design and the proportion of significant associations.

RESULTS

There were 109 studies included in this review (47 on NAFLD, 1 on liver fibrosis, 6 on liver cirrhosis, and 55 on HCC). Consistent evidence suggested that higher dietary inflammatory potential was associated with increased risk of both NAFLD and HCC whereas Mediterranean diet was associated with lower risk of both diseases. Additionally, greater conformity to the Healthy Eating Index, Dietary Approaches to Stop Hypertension score, and Mediterranean Diet Score, and dietary patterns with high dietary antioxidant capacity reduced NAFLD risk. Some specific foods including soft drinks and red and/or processed meat were associated with increased NAFLD risk while total vegetables and spinach were associated with reduced NAFLD risk. Coffee and white meat consumption were inversely related to HCC risk.

CONCLUSIONS

Dietary patterns or individual foods representing a more anti-inflammatory potential were associated with reduced risk of both NAFLD and HCC, which implied diet-induced inflammation may impact NAFLD progression towards HCC.

The effect of a fruit-rich diet on liver biomarkers, insulin resistance, and lipid profile in patients with non-alcoholic fatty liver disease: a randomized clinical trial

BACKGROUND

Despite confirmed dietary approaches to improve the Non-Alcoholic Fatty Liver Disease (NAFLD), the effect of fruits on NAFLD is not clear. The present study aimed to investigate the effect of a fruit rich diet (FRD) on liver steatosis, liver enzymes, Insulin resistance, and lipid profile in patients with NAFLD.

METHODS

Eighty adults with NAFLD participated in this randomized controlled trial. The participants were randomly assigned to the FRD group with consumption of at least 4 servings of fruits daily or the control group with fruits consumption of less than 2 servings/day. The grade of steatosis, serum levels of liver enzymes including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), glucose, and homeostatic model assessment for insulin resistance (HOMA-IR) were measured at the baseline and at the end of the study.

RESULTS

After 6 months of intervention, the FRD group had significantly higher BMI (31.40 ± 2.61 vs. 25.68 ± 2.54, p < .001), WC (113.5 ± 10.7 vs. 100.5 ± 7.5, p < .001), the grade of steatosis, ALT (89.1 ± 92.9 vs. 32.0 ± 19.2, p < .001), AST (74.5 ± 107.8 vs. 24.0 ± 8.5, p < .001), ALP (273.4 ± 128.5 vs. 155.0 ± 43.9, p < .001), GGT (92.7 ± 16.2 vs. 21.2 ± 7.7, p < .001), TC (206.1 ± 40.5 vs. 172.7 ± 42.4, p < .01), LDL (126.9 ± 32.3 vs. 99.8 ± 29.8, p < .001), glucose (115.5 ± 30.0 vs. 97.7 ± 19.0, p < .01), and insulin resistance (7.36 ± 4.37 vs. 2.66 ± 1.27, p < .001), and lower HDL (41.4 ± 8.9 vs. 53.8 ± 15.1, p < .001) compared to the control group. Adjusting for BMI and calorie intake did not change the results.

CONCLUSION

The results of the present study indicated that consumption of fruits more than 4 servings/day exacerbates steatosis, dyslipidemia, and glycemic control in NAFLD patients. Further studies are needed to identify the underlying mechanisms of the effects of fruits on NAFLD.

CLINICAL TRIAL REGISTRATION

This trial was registered at Iranian randomized clinical trial website with IRCT registration no. IRCT20201010048982N1on October 15, 2020.

Atherosclerosis and Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a common disease defined by excess fat deposition in the liver. The course of NAFLD is not fully understood, however, some pathogenic mechanisms have been identified. Accumulation of fat in liver cells is associated with insulin resistance, central obesity, triglyceride accumulation in the liver and hepatic fatty acid metabolism dysregulation that cause steatosis. The other process leads to hepatocyte inflammation and necrosis, which leads to severe hepatic disease; non-alcoholic steatohepatitis. Many clinical studies have underlined the link between NAFLD and atherosclerosis. NAFLD may alter the balance lipid-glucose metabolism as well as increase the risk of hypertension and systemic inflammation. This results in a greater risk of vascular events. The present review considers the link between NAFLD and atherosclerosis.

Empirically derived dietary pattern and odds of non-alcoholic fatty liver diseases in overweight and obese adults: a case-control study

Background

The prevalence of non-alcoholic fatty liver disease (NAFLD) is rising at an exponential rate throughout the world. Given the confirmed association between nutritional status and NAFLD, this study aimed to investigate the relationship of dietary patterns with NAFLD in overweight and obese adults.

Methods

In this age- and gender-matched case–control study, 115 newly diagnosed cases and 102 control individuals participated. A validated 178-item semi-quantitative food frequency questionnaire was administered to assess the participants' dietary data. Dietary patterns were extracted from 24 predefined food groups by factor analysis. Multivariate logistic regression was run to evaluate the relationship between dietary patterns and NAFLD.

Results

Factor analysis resulted in: “western”, “traditional”, and “snack and sweets” dietary patterns. The NAFLD odds were greater in participants at the highest quintile of the “western” dietary pattern than the lowest quintile (OR: 3.52; 95% CI: 1.64, 8.61). A significant increasing trend was observed in NAFLD odds across increasing quintiles of the “western” dietary pattern (P-trend = 0.01). After adjusting for the potential confounders, this relationship remained significant (OR: 3.30; 95% CI: 1.06–10.27). After full adjustments, NAFLD had no association with “traditional” or “snack and sweets” dietary patterns.

Conclusion

The “western” dietary pattern containing fast food, refined grains, liquid oil, pickles, high-fat dairy, sweet desserts, red meat, tea, and coffee was associated with increased odds of NAFLD. However, further prospective studies are required to establish these results.

Dietary Vitamin C Intake Is Associated With Improved Liver Function and Glucose Metabolism in Chinese Adults

Background

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent chronic liver diseases worldwide. Dietary vitamin C intake might play an important role in reducing the risk of NAFLD. This study assesses the relationship between dietary vitamin C intake and diagnostic biomarkers of NAFLD.

Methods

The data from the 2009 China Health and Nutrition Survey (CHNS), nine provinces across four diverse regions (Northeast, East Coast, Central, and West) were included in the study. The dietary vitamin C intake of participants was calculated based on 3-day 24-h diet questionnaires at the individual level. The associations of dietary vitamin C intake and the biochemical indicators of liver function and glucose/lipid metabolism were determined.

Results

A total of 8,307 participants were included in the final analysis. The mean dietary vitamin C intake for the overall, male and female subjects was 79.8 ± 58.6, 81.6 ± 55.3, and 78.2 ± 61.2 mg/day, respectively. The prevalence of inadequate dietary vitamin C intake for the overall, male and female subjects was 24.4, 26.5, and 22.6%, respectively. Intake of vitamin C was associated with both lower concentrations of plasma ferritin and hemoglobin A1c (HbA1c). Higher dietary vitamin C intake was associated with higher albumin, even further adjusted for body mass index (BMI), residence, and smoking status. No improvement in lipid metabolism was found.

Conclusion

This study demonstrated that higher dietary vitamin C intake is a benefit for improving glucose metabolism and liver function in which reducing ferritin, a biomarker of iron accumulation, may be involved.

Diet and gut microbiome in fatty liver and its associated liver cancer

Non-alcoholic fatty liver disease (NAFLD) is the major cause of chronic liver disease worldwide as a consequence of a sedentary lifestyle and overnutrition. NAFLD could progress to non-alcoholic steatohepatitis (NASH), which may further develop to cirrhosis and hepatocellular carcinoma (HCC). The gut microbiome is one of the central regulators in host metabolism. Diet could change human gut microbiome rapidly and reproducibly and modulate several metabolic pathways. Both diet and gut microbiome dysbiosis are associated with NAFLD and its related HCC (NAFLD-HCC). Dietary cholesterol, fiber, fat, or carbohydrate could change the microbiome composition to contribute to the development of NASH and NAFLD-HCC. Hence, identification of elements of the gut-liver axis that are primarily damaged in NASH and NAFLD-HCC offers new possibility for therapeutic intervention. In this review, the roles of gut microbiome and microbial metabolites in the development and progression of NAFLD and NAFLD-HCC are first discussed. The impacts of different diet compositions including cholesterol, fiber, fat, and sugar on the gut microbiome that leads to predisposition to NASH and NAFLD-HCC are also explored. We summarized the article by discussing potential therapeutic implication of diet and microbiome modulation in fatty liver and liver cancer.

Systematic Review and Meta-analysis: The Role of Diet in the Development of Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

The association of nonalcoholic fatty liver disease (NAFLD) with dietary factors is well established but not thoroughly investigated. This systematic review and meta-analysis synthesizes available evidence regarding the effect of nutrition on the presence and severity of NAFLD.

METHODS

A literature search was conducted identifying studies published between January 1985 and May 2021. We included studies with a dietary assessment and anthropometry based on validated tools, performed by a qualified dietitian or a trained health professional. We examined differences between patients with NAFLD and healthy controls as well as patients with NAFLD and nonalcoholic steatohepatitis (NASH). Risk of bias was assessed with the Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I) tool.

RESULTS

There were 60 eligible studies with 100,621 patients. The risk of bias was moderate for the majority of studies (41/60; 68%). According to meta-analyses, total caloric intake was higher in patients with NAFLD compared with controls (mean difference, 78.08; 95% confidence interval, 41.03-115.13). Macronutrient (protein, fat, and carbohydrate) consumption as proportion of total caloric intake and daily intake of fiber, caffeine and vitamins E, A, and C did not significantly differ between patients with NAFLD and controls. Soft drink consumption had a trend towards association with the presence of NAFLD. However, the odds ratio was 4.4 and the confidence intervals very wide. Finally, there was no significant difference in any comparison between patients with NAFLD and NASH, although the number of patients was relatively small. All meta-analyses had significant heterogeneity.

CONCLUSIONS

Overall, despite high heterogeneity among studies, this meta-analysis demonstrated that higher caloric intake is positively associated with NAFLD, whereas diet composition in macronutrients was not associated with the presence or severity of the disease.

The Role of Vitamin Deficiency in Liver Disease: To Supplement or Not Supplement?

Over the past few years, growing interest has been shown for the impact of dietary requirements and nutritional factors on chronic diseases. As a result, nutritional programs have been reinforced by public health policies. The precise role of micronutrients in chronic liver disease is currently receiving particular attention since abnormalities in vitamin levels are often detected. At present, treatment programs are focused on correcting vitamin deficiencies, which are frequently correlated to higher rates of comorbidities with poor outcomes. The literature reviewed here indicates that liver diseases are often related to vitamin disorders, due to both liver impairment and abnormal intake. More specific knowledge about the role of vitamins in liver disease is currently emerging from various results and recent evidence. The most significant benefits in this area may be observed when improved vitamin intake is combined with a pharmacological treatment that may also affect the progression of the liver disease, especially in the case of liver tumors. However, further studies are needed.

Intake of Nuts and Seeds Is Associated with a Lower Prevalence of Nonalcoholic Fatty Liver Disease in US Adults: Findings from 2005-2018 NHANES

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease globally. Nuts and seeds, due to their unique nutrient composition, may provide health benefits for the prevention of NAFLD. To date, no research has investigated the association between nut and seed intake and NAFLD prevalence in a non-Mediterranean Western population.

OBJECTIVES

This study aimed to explore the association between nut and seed intake with NAFLD and metabolic biomarkers in a US representative sample.

METHODS

This cross-sectional study used data from 25,360 adults involved in the 2005-2018 NHANES, including adults (aged ≥18 y) with negative serology for hepatitis B and C and nonexcessive alcohol consumption. NAFLD was assessed using the fatty liver index (FLI); metabolic biomarkers were also assessed; nut and seed intake was evaluated from two 24-h dietary recalls. ANOVA and Poisson regression were used to establish the relation between nut and seed intake categories and NAFLD prevalence.

RESULTS

Nut and seed consumption was associated with a reduced prevalence of NAFLD. In females, in the fully adjusted model, this was significant across all nut and seed consumption categories but was most prominent in the moderate consumption group (7%, 15%, and 14% risk reduction in low, moderate, and adequate consumption categories, respectively, compared with nonconsumers). In males, moderate intake of nuts and seeds demonstrated a significantly lower prevalence of NAFLD (9%) compared with nonconsumers.

CONCLUSIONS

Daily consumption for nuts and seeds was associated with a lower prevalence of NAFLD in non-Mediterranean, US adults, although the benefits seem to be greater in females across all categories of nut and seed consumption groups compared with nonconsumers. Both males and females presented with lower prevalence of NAFLD with intakes of 15-30 g/d.

Effects of Oral Vitamin C Supplementation on Liver Health and Associated Parameters in Patients With Non-Alcoholic Fatty Liver Disease: A Randomized Clinical Trial

Non-alcoholic fatty liver disease (NAFLD) is now recognized as the most prevalent hepatic disorder worldwide, and an unhealthy lifestyle is the leading risk factor for its occurrence. Vitamin C (VC) has been suggested to protect NAFLD, whereas evidence from randomized controlled trials (RCTs) is sparse. In this study, we aimed to investigate the potential benefits of VC supplementation daily on liver health and associated parameters in patients with NAFLD. In this double-blind, RCT, 84 patients with NAFLD, aged 18-60 years old, were assigned to 12 weeks of oral treatment with either low (250 mg/day, n = 26), medium (1,000 mg/day, n = 30), or high (2,000 mg/day, n = 28) doses of VC supplements. After the intervention, the Medium group had a more significant decrease in aspartate aminotransferase [Medium, -5.00 (-10.25, -1.75) vs. High, -2.50 (-7.75, 0.00), P = 0.02] and alanine aminotransferase [Medium, -8.00 (-18.00, -1.75) vs. High, -3.50 (-13.75, 4.25), P = 0.05; Medium vs. Low, -3.00 (-9.00, 5.50), P = 0.031]. The levels of other indicators of liver health, such as gamma-glutamyl transferase, alkaline phosphatase, total bilirubin, and direct bilirubin were decreased after the intervention but comparable among the three groups and so did the parameters of glucose metabolism, such as fasting insulin, fasting glucose, and homeostasis model assessment for insulin resistance. The plasma level of VC in patients and total adiponectin and high molecular weight (HMW) adiponectin levels were also elevated but not in a dose-dependent manner. Meanwhile, analysis of fecal microbiota composition showed an increase in the alpha diversity (Abundance-based Coverage Estimator (ACE), Shannon, chao1, and Simpson) both in the Low and the Medium groups. A total of 12 weeks of VC supplementation, especially 1,000 mg/day, improved liver health and glucose metabolism in patients with NAFLD. The elevated plasma levels of VC, total and HMW adiponectin, and the improvement of intestinal microbiota may have made some contributions.

Impact of dietary compositions and patterns on the prevalence of nonalcoholic fatty liver disease in Japanese men: a cross-sectional study

BACKGROUND

This study aimed to examine the impact of dietary compositions and patterns on nonalcoholic fatty liver disease (NAFLD) morbidity in Japanese men.

METHODS

We conducted a cross-sectional study of 281 individuals who underwent comprehensive medical examinations during health screening. Dietary intake was assessed using a semi-quantitative food frequency questionnaire, and factor analysis was performed to detect dietary patterns. NAFLD was diagnosed by the presence of fatty liver on abdominal ultrasonography in nondrinkers (< 30 g/day), and patients were categorized into control (n = 192) and NAFLD groups (n = 89).

RESULTS

Compared with the control group, the NAFLD group consumed fewer mushrooms. Three dietary patterns were identified, namely, a healthy pattern, a western pattern, and a snack pattern. The score of healthy pattern was negatively correlated with the risk of NAFLD. Compared with the lowest tertile of the healthy pattern, the middle tertile was associated with a lower risk of NAFLD after adjusting for age, physical activity, and smoking (odds ratio: 0.47, 95% confidence interval: 0.25-0.91). After further adjustments for body mass index, the middle tertile was associated with a lower risk of NAFLD (odds ratio: 0.46, 95% confidence interval: 0.23-0.92).

CONCLUSIONS

A healthy dietary pattern comprising frequent intake of seaweeds, vegetables, mushrooms, pulses, and potatoes and starches was associated with a lower risk of NAFLD in Japanese men. In our opinion, this healthy pattern closely resembles the Japanese Washoku diet, indicating that adherence to Washoku may help prevent NAFLD.

Walnut-Enriched Diet Elevated α-Linolenic Acid, Phytoprostanes, and Phytofurans in Rat Liver and Heart Tissues and Modulated Anti-inflammatory Lipid Mediators in the Liver

α-Linolenic acid (ALA) and its non-enzymatic oxidized products, namely, phytoprostanes and phytofurans, are found in some nuts. The uptake and deposition of these compounds are not well-defined. Walnut has high ALA and a considerable amount of phytoprostanes and phytofurans compared to other common nuts. When fed to rodents, ALA and eicosapentaenoic acid levels increased in the liver and heart tissues compared to the control diet. Furthermore, phytoprostanes and phytofurans were elevated 3-fold in both tissues after a walnut diet, indicating that they are not only contributed from the diet but also generated through in vivo autoxidation of ALA found in the walnuts. It was further noted that a walnut diet reduced 5-F_2t-isoprostanes and 12-hydroxyeicosatetraenoic acid and induced 4-F_4t-neuroprostane and significant amounts of anti-inflammatory hydroxydocosahexaenoic acid in the liver only. Altogether, high ALA in a walnut diet elevated phytoprostanes and phytofurans in the liver and heart tissues and showed the regulation of anti-inflammatory lipid mediators in the liver only.

Clinical impact of sexual dimorphism in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH)

NAFLD/NASH is a sex-dimorphic disease, with a general higher prevalence in men. Women are at reduced risk of NAFLD compared to men in fertile age, whereas after menopause women have a comparable prevalence of NAFLD as men. Indeed, sexual category, sex hormones and gender habits interact with numerous NAFLD factors including cytokines, stress and environmental factors and alter the risk profiles and phenotypes of NAFLD. In the present review, we summarized the last findings about the influence of sex on epidemiology, pathogenesis, progression in cirrhosis, indication for liver transplantation and alternative therapies, including lifestyle modification and pharmacological strategies. We are confident that an appropriate consideration of sex, age, hormonal status and sociocultural gender differences will lead to a better understanding of sex differences in NAFLD risk, therapeutic targets and treatment responses and will aid in achieving sex-specific personalized therapies.

A nomogram incorporated lifestyle indicators for predicting nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, and its pathogenesis is complicated and triggered by unbalanced diet, sedentary lifestyle, and genetic background. The aim of this study was to construct and validate a nomogram incorporated lifestyle habits for predicting NAFLD incidence.The overall cohort was divided into training set and test set as using computer-generated random numbers. We constructed the nomogram by multivariate logistic regression analysis in the training set. Thereafter, we validated this model by concordance index, the area under the receiver operating characteristic curve (ROC), net reclassification index, and a calibration curve in the test set. Additionally, we also evaluated the clinical usefulness of the nomogram by decision curve analysis.There were no statistically significant differences about characteristics between training cohort (n = 748) and test cohort (n = 320). Eleven features (age, sex, body mass index, drinking tea, physical exercise, energy, monounsaturated fatty acids, polyunsaturated fatty acids, hypertension, hyperlipidemia, diabetes) were incorporated to construct the nomogram, concordance index, the area under the ROC curve, net reclassification index were 0.801, 0.801, and 0.084, respectively, indicating the nomogram have good discrimination of predicting NAFLD incidence. Also, the calibration curve showed good consistency between nomogram prediction and actual probability. Moreover, the decision curve showed that when the threshold probability of an individual is within a range from approximately 0.5 to 0.8, this model provided more net benefit to predict NAFLD incidence risk than the current strategies.This nomogram can be regarded as a user-friendly tool for assessing the risk of NAFLD incidence, and thus help to facilitate management of NAFLD including lifestyle and medical interventions.

Vitamins and non-alcoholic fatty liver disease: A Molecular Insight⋆

The incidence of non-alcoholic fatty liver disease (NAFLD) is rising rapidly across the globe. NAFLD pathogenesis is largely driven by an imbalance in hepatic energy metabolism and at present, there is no approved drug for its treatment. The liver plays a crucial role in micronutrient metabolism and deregulation of this micronutrient metabolism may contribute to the pathogenesis of NAFLD. Vitamins regulate several enzymatic processes in the liver, and derangement in vitamin metabolism is believed to play a critical role in NAFLD progression. The anti-oxidant activities of vitamin C and E have been attributed to mitigate hepatocyte injury, and alterations in the serum levels of vitamin D, vitamin B12 and folate have shown a strong correlation with NAFLD severity. This review aims to highlight the role of these vitamins, which represent promising therapeutic targets for the management of NAFLD.

Dietary and sociodemographic factors associated with nonalcoholic fatty liver in obese pediatric patients

INTRODUCTION

Obesity is associated with nonalcoholic fatty liver disease (NAFLD) in children. Our aim was to analyze the association of dietary and sociodemographic factors with NAFLD in obese children and adolescents.

MATERIALS AND METHODS

Thirty-three obese patients from 6-16 years of age were included in the present analytic cross-sectional study. Obesity was diagnosed with a body mass index z-score > 2 SD. NAFLD was estimated by liver ultrasound, serum amino transferases, and elastography. The sociodemographic variables were evaluated using validated questionnaires. Diet was estimated through two 24-h recall dietary surveys focused on the quantity of food energy, simple sugars, polyunsaturated fatty acids (PUFAs), and antioxidants.

RESULTS

Hepatic steatosis was identified by abdominal ultrasound in 13 patients (39.4%) and the serum alanine aminotransferase level was above the upper reference value in 54.2%. A higher educational level in both parents, greater monthly food expenditure, and a higher socioeconomic level were associated with NAFLD. Overall, simple sugar and saturated fat consumption was above the recommended daily intake, whereas vitamin E and PUFA consumption was below those parameters.

CONCLUSIONS

NAFLD was identified in one-third of the cases. There was an association between NAFLD and sociodemographic variables. Both groups had an increased intake of simple sugars and a reduced intake of PUFAs. The selective occurrence of NAFLD could be related to a genetic predisposition that has been demonstrated in a Mexican population.

Associations between nut intake, cognitive function and non-alcoholic fatty liver disease (NAFLD) in older adults in the United States: NHANES 2011-14

BACKGROUND

Nuts are nutrient-rich and reported to provide some cognitive and cardiometabolic health benefits, but limited studies have focused on older adults. This study investigated the cross-sectional relationship between habitual nut intake, dietary pattern and quality, cognition and non-alcoholic fatty liver disease (NAFLD) in older adults.

METHODS

Older adults (≥ 60 years) from the NHANES 2011-12 and 2013-14 cohorts, who had complete data on cognitive function (as CERAD total, delayed recall, animal fluency and digit-symbol substitution test) and variables to calculate the Fatty Liver Index (FLI), an indicator of NAFLD, were included (n = 1848). Nut intake and diet quality (Healthy Eating Index 2015) were determined using two 24-hour diet recalls. Participants were categorised into one of four groups based on their habitual nut intake: non-consumers (0 g/d), low intake (0.1-15.0 g/d), moderate intake (15.1-30.0 g/d) or met recommendation (> 30 g/d), with all outcomes compared between these nut intake groups.

RESULTS

Cognitive scores of older adults were the lowest in non-consumers and significantly highest in the moderate intake group, with no further increase in those who consumed nuts more than 30 g/d (p < 0.007). FLI was the lowest among older adults with moderate nut intake but the associations disappeared after adjusting for covariates (p = 0.329). Moderate nut intake was also associated with better immediate and delayed memory in older adults with high risk of NAFLD (FLI ≥ 60) (B = 1.84 and 1.11, p < 0.05 respectively). Higher nutrient intake and better diet quality (p < 0.001) were seen with higher nut intake but did not influence energy from saturated fat intake. Factor analysis revealed 'Nuts and oils' as one of the four major dietary patterns associated with better cognition and lower FLI scores.

CONCLUSIONS

Moderate nut intake (15.1-30.0 g/d) may be sufficient for better cognitive performance, but not NAFLD risk of older adults in the US.

Nut consumption and the prevalence and severity of non-alcoholic fatty liver disease

BACKGROUND

Nut consumption has been associated with reduced inflammation, insulin resistance, and oxidative stress. However, the influence on the prevalence and severity of non-alcoholic fatty liver disease (NAFLD) has yet to be evaluated.

METHODS

4655 subjects were included as part of a colorectal carcinoma screening program (SAKKOPI) between 07/2010 and 07/2019 and analyzed 2020. Patients were characterized using biochemical and metabolic parameters, as well as a detailed questionnaire on dietary habits. The diagnosis of NAFLD was established using abdominal ultrasound. Consumption of nuts was graded as: no consumption or <1 time/week, 1-6 times/week, 1 time/day and ≥2 times/day.

RESULTS

Mean age was 58.5±9.8years with a mean BMI of 26.5±4.7kg/m2. 2058 (44.2%) patients suffered from the metabolic syndrome, 2407 (51.6%) had arterial hypertension, 2287 (49.1%) showed prediabetes/diabetes, 1854 (39.4%) had dyslipidemia and 1984 patients (43.5%) were diagnosed with NAFLD. Prevalence of metabolic syndrome (1219 [48.7%] vs. 605 [40.2%] vs. 189 [37.4%] vs. 45 [31.7%], p<0.001) and NALFD (1184 [48.1%] vs. 594 [40.7%] vs. 158 [31.7%] vs. 48 [34.0%], p<0.001). On multivariable logistic regression analysis adjusting for potential confounders and dietary patterns, nut consumption ≥1time/day was inversely associated with NAFLD in the overall cohort (adjusted Odds ratio[aOR]: 0.719 [95%CI:0.558-0.926], p = 0.011). However, following subgroup analysis, this inverse association was only confirmed in male patients (aOR: 0.589 [95%CI: 0.411-0.844], p = 0.004) but not in females (aOR: 0.886 [95%CI: 0.616-1.275], p = 0.515). Moreover, patients who consumed nuts 1-6 times/week had a significantly lower prevalence of advanced fibrosis (Fib-4 score >2.67: aOR: 0.551 [95%CI: 0.338-0.898], p = 0.017; Forns-Index >6.9: aOR: 0.585 [95%CI: 0.402-0.850], p = 0.005).

CONCLUSIONS

Nut consumption might exert beneficial effects on the prevalence of NAFLD in males. The negative association with advanced fibrosis warrants further investigation.

Nuts and Non-Alcoholic Fatty Liver Disease: Are Nuts Safe for Patients with Fatty Liver Disease?

Diet and lifestyle interventions are the recommended treatment for patients with non-alcoholic fatty liver disease (NAFLD), with the aim of achieving a 7-10% weight loss. Several dietary patterns have been suggested for this purpose, however, to date, the best one is represented by the Mediterranean diet (MD) as it is rich in macro- and micro- nutrients known for their effectiveness in health-promotion and cardio-vascular disease prevention. Moreover, MD is characterized by the inclusion of nuts. These foods have shown potential benefits in health-promotion as they are rich in fibers, which have lipid-lowering effects, rich in mono- and poly-unsaturated fatty acids, which help reduce insulin-resistance and serum cholesterol, and contain anti-oxidants which reduce oxidative stress and inflammation. Additionally, nuts are associated with a better control, or reduction, of Body Mass Index (BMI). All these effects are useful targets to achieve in NAFLD, so that nuts have been proposed as a suitable dietary treatment supplement for weight and metabolic control in these patients. In recent years, health authorities raised an alert on nuts consumption as these may be at high risk of aflatoxin (AF) contamination, for which controls and legislations are different among countries. AF is a well-known cancerogenic agent and a recognized risk factor for hepatocellular carcinoma. Patients with NAFLD have an overall, inherent sevenfold increased risk of developing hepatocellular carcinoma as compared with the general population. In this context, one could argue that recommending the inclusion of nuts in the diet of NAFLD patients has to be balanced with the risk of potential chronic exposure to AF, and every effort should be pursued to assure the safety of these nutrients. In this review, we aim to summarize the benefits of nuts consumption, the evidence for AF contamination of nuts and the consequent potential risks in patients with NAFLD.

Prophylactic and therapeutic effects of different doses of vitamin C on high-fat-diet-induced non-alcoholic fatty liver disease in mice

Epidemiological studies support the association between inadequate vitamin C (Vc) intake and non-alcoholic fatty liver disease (NAFLD). However, the intervention dose of Vc, and the prophylactic and therapeutic effects on NAFLD are unclear. This study aimed to investigate the prophylactic and therapeutic effects of low (LVc), medium (MVc) and high (HVc) doses of Vc on NAFLD. C57BL/6 mice were randomly assigned to prophylactic groups (mice received a high-fat diet (HFD) concomitant with different doses of Vc) and therapeutic groups (HFD-induced NAFLD mice treated with different doses of Vc). Results showed that prophylactic LVc and MVc administration reduced the risk of NAFLD development in HFD-fed mice, as evidenced by significantly lowered body weight, perirenal adipose tissue mass, and steatosis, whereas prophylactic HVc administration did not prevent HFD-induced NAFLD development. Furthermore, therapeutic MVc administration significantly ameliorated HFD-induced increase in body weight, perirenal adipose tissue mass and steatosis, whereas therapeutic LVc and HVc administration did not ameliorate NAFLD symptoms. In fact, therapeutic HVc administration significantly increased body weight, perirenal adipose tissue mass, and lobular inflammation. Moreover, prophylactic LVc administration was more effective than therapeutic LVc administration as evidenced by significantly lower body weight, perirenal adipose tissue mass, steatosis, ballooned hepatocytes, and lobular inflammation in prophylactic LVc administration. The same trends were observed between prophylactic HVc administration and therapeutic HVc administration. In addition, all Vc-administered mice exhibited low blood glucose, triglycerides and homeostasis model assessment of insulin resistance values and high adiponectin levels compared to HFD-fed mice. Our study suggested that MVc was beneficial for HFD-induced NAFLD prophylaxis and therapy. LVc prevented HFD-induced NAFLD development, while HVc for NAFLD management was risky. This study offers valuable insight into the effect of various Vc doses on NAFLD management.

Negative association between antioxidant vitamin intake and non-alcoholic fatty liver disease in Chinese non-diabetic adults: mediation models involving superoxide dismutase

We aimed to explore the association between antioxidant vitamin intake, oxidative stress related markers and non-alcoholic fatty liver disease (NAFLD) by a cross-sectional analysis. A total of 241 non-diabetic participants from a Chinese rural cohort were included. NAFLD was diagnosed by abdominal ultrasound (NAFLD, n = 71; Non-NAFLD, n = 171). Dietary intake was assessed by a 24-h food recall. Plasma oxidative stress related markers superoxide dismutase (SOD), glutathione reductase (GR) and 8-oxo-2'-deoxyguanosine(8-oxo-dG) were measured. The association between dietary antioxidant vitamin intake, oxidative stress related markers and NAFLD were analysed by Spearman correlation analysis and multiple logistic regression analysis. Mediation models were established to examine whether SOD mediated the association between dietary vitamin A or α-tocopherol intake and NAFLD. Spearman correlation analysis indicated that dietary vitamin A and α-tocopherol intake were positively correlated with SOD (p < .05). Multiple logistic regression analysis found plasma SOD, dietary vitamin A and α-tocopherol intake were inversely associated with NAFLD (all p < .05). Mediation analysis indicated that SOD significantly mediated the indirect effect of dietary α-tocopherol (mediated effect = 13.21% total effect) or vitamin A (mediated effect = 3.12% total effect) intake on NAFLD. Our study indicated that dietary vitamin A and α-tocopherol intake may contribute to protect from NAFLD in Chinese non-diabetics, and the associations were partly mediated by SOD. However, SOD only accounted for a minor percentage of the association between vitamin A intake and NAFLD. Thus, other mechanisms underlying antioxidant vitamin' protective effect on NAFLD need further exploration.

Fruit and vegetable consumption and non-alcoholic fatty liver disease among Korean adults: a prospective cohort study

BACKGROUND

Diet is an important risk factor contributing to the development of non-alcoholic fatty liver disease (NAFLD) and associated metabolic co-morbidities (obesity or metabolic syndrome). This study aimed to investigate the association between fruit and vegetable consumption and NAFLD risk according to sex among Korean adults.

METHODS

We included 52 280 participants from the Health Examinees study cohort. The cumulative average intake of fruits and vegetables was estimated using a validated semi-quantitative food frequency questionnaire. Cox proportional hazards regression analysis was performed to estimate relative risk (RR) and 95% CI of NAFLD according to the quintiles of fruit and vegetable consumption.

RESULTS

During 4.2 years of follow-up, 2130 cases of NAFLD were documented. In women, higher consumption of fruits (RR 0.77; 95% CI 0.62 to 0.96) and vegetables (RR 0.71; 95% CI 0.56 to 0.88) was associated with lower NAFLD risk (p for trend=0.0106 and 0.0071, respectively). Men showed a decreasing tendency of NAFLD risk according to vegetable consumption (p for trend =0.0374). Higher total intakes of fruits and vegetables were significantly associated with lower NAFLD risk in men (RR 0.75; 95% CI 0.62 to 0.92, p for trend =0.0047) and women (RR 0.74; 95% CI 0.59 to 0.93, p for trend =0.0021).

CONCLUSION

Fruit intake, vegetable intake, and total fruit and vegetable intake were associated with reduced NAFLD risk. Fruit and vegetable consumption can protect against NAFLD and associated metabolic co-morbidities.

Study protocol for a 9-month randomised controlled trial assessing the effects of almonds versus carbohydrate-rich snack foods on weight loss and weight maintenance

INTRODUCTION

Epidemiological studies indicate an inverse association between nut consumption and body mass index (BMI). However, clinical trials evaluating the effects of nut consumption compared with a nut-free diet on adiposity have reported mixed findings with some studies reporting greater weight loss and others reporting no weight change. This paper describes the rationale and detailed protocol for a randomised controlled trial assessing whether the inclusion of almonds or carbohydrate-rich snacks in an otherwise nut-free energy-restricted diet will promote weight loss during 3 months of energy restriction and limit weight regain during 6 months of weight maintenance.

METHODS AND ANALYSIS

One hundred and thirty-four adults aged 25-65 years with a BMI of 27.5-34.9 kg/m² will be recruited and randomly allocated to either the almond-enriched diet (AED) (15% energy from almonds) or a nut-free control diet (NFD) (15% energy from carbohydrate-rich snack foods). Study snack foods will be provided. Weight loss will be achieved through a 30% energy restriction over 3 months, and weight maintenance will be encouraged for 6 months by increasing overall energy intake by ~120-180 kcal/day (~500-750kJ/day) as required. Food will be self-selected, based on recommendations from the study dietitian. Body composition, resting energy expenditure, total daily energy expenditure (via doubly labelled water), physical activity, appetite regulation, cardiometabolic health, gut microbiome, liver health, inflammatory factors, eating behaviours, mood and personality, functional mobility and pain, quality of life and sleep patterns will be measured throughout the 9-month trial. The effects of intervention on the outcome measures over time will be analysed using random effects mixed models, with treatment (AED or NFD) and time (baseline, 3 months and 9 months) being the between and within factors, respectively in the analysis.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the University of South Australia Human Research Ethics Committee (201436). Results from this trial will be disseminated through publication in peer-reviewed journals, national and international presentations.

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry (ACTRN12618001861246).

A Description of Risk Factors for Non-alcoholic Fatty Liver Disease in the Southern Community Cohort Study: A Nested Case-Control Study

Background: Non-alcoholic fatty liver disease (NAFLD) is associated with obesity and hypercholesterolemia. In addition, total fat and folate intake have been associated with NAFLD.

Aims: We investigated risk factors for NAFLD among individuals of largely low socioeconomic status, and whether these associations differed by race.

Methods: A nested case-control study was conducted within the Southern Community Cohort Study. Through linkage of the cohort with Centers for Medicare and Medicaid Services, International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify incident NAFLD cases. Controls were matched 4:1 to cases on enrollment age, sex, and race. A logistic regression was used to estimate odds ratios for the associations of NAFLD with covariates of interest.

Results: Neither total fat nor folate intake was significantly associated with NAFLD. Hypercholesterolemia (odds ratio 1.21) and body mass index (75th vs. 25th percentile) for blacks (odds ratio 1.96) and whites (odds ratio 2.33) were associated with an increased risk of non-alcoholic fatty liver disease. No significant interaction with race for any of the studied variables was noted.

Conclusions: Both hypercholesterolemia and increasing body mass index, but not total fat and folate intake, were risk factors for NAFLD in the Southern Community Cohort Study.

Serum Malondialdehyde is Associated with Non-Alcoholic Fatty Liver and Related Liver Damage Differentially in Men and Women

Background: Non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) are associated with increased oxidative stress and lipid peroxidation, but large studies are lacking. The aim was to test the association of malondialdehyde (MDA), as a marker of oxidative damage of lipids, with NAFLD and liver damage markers, and to test the association between dietary vitamins E and C intake and MDA levels. Methods: A cross-sectional study was carried out among subjects who underwent blood tests including FibroMax for non-invasive assessment of NASH and fibrosis. MDA was evaluated by reaction with Thiobarbituric acid and HPLC-fluorescence detection method. NAFLD was diagnosed by abdominal ultrasound. Findings: MDA measurements were available for 394 subjects. In multivariate analysis, the odds for NAFLD were higher with the rise of MDA levels in a dose–response manner, adjusting for age, gender, BMI, and lifestyle factors. Only among men, higher serum MDA was associated of higher odds for NAFLD and NASH and/or fibrosis (OR = 2.59, 95% CI 1.33–5.07, P = 0.005; OR = 2.04, 1.02–4.06, P = 0.043, respectively). Higher vitamin E intake was associated with lower odds of high serum MDA level (OR = 0.28 95% CI 0.13–0.62, P = 0.002). In conclusion, serum MDA is associated with NAFLD and markers of NASH or fibrosis among men. Dietary vitamin E may be protective among women.

Diet Associations With Nonalcoholic Fatty Liver Disease in an Ethnically Diverse Population: The Multiethnic Cohort

BACKGROUND AND AIMS

Epidemiological data on dietary risk factors for nonalcoholic fatty liver disease (NAFLD) from population-based studies, particularly in an ethnically diverse population, are scarce. We examined dietary factors in relation to NAFLD risk in African Americans, Japanese Americans, Latinos, native Hawaiians, and whites in the Multiethnic Cohort (MEC).

APPROACH AND RESULTS

A nested case-control analysis was conducted within the MEC, a large prospective study with >215,000 older adult participants in Hawaii and California. NAFLD was identified using Medicare claims data, and controls were selected among participants without liver disease and individually matched to cases by birth year, sex, ethnicity, and length of Medicare enrollment. Diet was assessed at baseline through a validated quantitative food frequency questionnaire. Diet-NAFLD associations were quantified by odds ratios and 95% confidence intervals using multivariable conditional logistic regression. The study consisted of 2,974 NAFLD cases (518 with cirrhosis, 2,456 without cirrhosis) and 29,474 matched controls. Red meat (P trend = 0.010), processed red meat (P trend = 0.004), poultry (P trend = 0.005), and cholesterol (P trend = 0.005) intakes were positively associated with NAFLD, while dietary fiber intake (P trend = 0.003) was inversely associated with risk. Stronger associations were observed between red meat and cholesterol and NAFLD with cirrhosis than without cirrhosis (P heterogeneity ≤0.014).

CONCLUSIONS

Dietary factors are independently associated with NAFLD and NAFLD-related cirrhosis in a multiethnic population. Decreasing the consumption of cholesterol, red and processed meat, and poultry and increasing consumption of fiber may reduce the risk for NAFLD and related advanced liver disease.

Diet and liver cancer risk: a narrative review of epidemiological evidence

Primary liver cancer is the third leading cause of cancer-related death worldwide. Most patients are diagnosed at late stages with poor prognosis; thus, identification of modifiable risk factors for primary prevention of liver cancer is urgently needed. The well-established risk factors of liver cancer include chronic infection with hepatitis B virus (HBV) or hepatitis C virus (HCV), heavy alcohol consumption, metabolic diseases such as obesity and diabetes, and aflatoxin exposure. However, a large proportion of cancer cases worldwide cannot be explained by current known risk factors. Dietary factors have been suspected as important, but dietary aetiology of liver cancer remains poorly understood. In this review, we summarised and evaluated the observational studies of diet including single nutrients, food and food groups, as well as dietary patterns with the risk of developing liver cancer. Although there are large knowledge gaps between diet and liver cancer risk, current epidemiological evidence supports an important role of diet in liver cancer development. For example, exposure to aflatoxin, heavy alcohol drinking and possibly dairy product (not including yogurt) intake increase, while intake of coffee, fish and tea, light-to-moderate alcohol drinking and several healthy dietary patterns (e.g. Alternative Healthy Eating Index) may decrease liver cancer risk. Future studies with large sample size and accurate diet measurement are warranted and need to consider issues such as the possible aetiological heterogeneity between liver cancer subtypes, the influence of chronic HBV or HCV infection, the high-risk populations (e.g. cirrhosis) and a potential interplay with host gut microbiota or genetic variations.

IMPACT OF CURRENT DIET AT THE RISK OF NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD)

The nonalcoholic fatty liver disease (NAFLD) affects approximately 20%-30% of general population and is even more prevalent among obese individuals. The risk factors mainly associated with NAFLD are diseases related to the metabolic syndrome, genetics and environment. In this review, we provide a literature compilation evaluating the evidence behind dietary components, including calories intake, fat, protein, fibers and carbohydrate, especially fructose which could be a trigger to development and progression of the NAFLD. In fact, it has been demonstrated that diet is an important factor for the development of NAFLD and its association is complex and extends beyond total energy intake.

Insoluble dietary fibre intake is associated with lower prevalence of newly-diagnosed non-alcoholic fatty liver disease in Chinese men: a large population-based cross-sectional study

BACKGROUND

The health benefits of dietary fibre (DF) intake on non-alcoholic fatty liver disease (NAFLD) are controversial. Thus, this large cross-sectional study aimed to determine the associations between DF intake and the prevalence of newly-diagnosed NAFLD in a large general population.

METHODS

A total of 23,529 participants were enrolled in the analyses. Newly-diagnosed NAFLD was diagnosed according to liver ultrasonography and history of alcohol intake. DF intake was assessed using a validated self-administered food frequency questionnaire. Logistic regression analysis was applied to estimate the associations between DF intake and NAFLD.

RESULTS

In total, 18.81% (n = 4426) of the participants were newly diagnosed with NAFLD. Compared with the participants in the lowest quartile of DF intake, the ORs (95% CI) for the participants in the highest quartile were 0.81 (0.67, 0.97), 0.78 (0.62, 0.99), and 0.85 (0.62, 1.17) for all participants, men, and women, respectively. Compared with the participants in the lowest quartile of insoluble DF intake, the ORs (95% CI) for the participants in the highest quartile were 0.70 (0.58, 0.85), 0.60 (0.47, 0.76), and 0.95 (0.68, 1.32) in all participants, men, and women, respectively. No association was observed between soluble DF intake and NAFLD. DF from whole grain, soy foods, vegetables, and nuts but not fruits were negatively associated with NAFLD.

CONCLUSIONS

A higher intake of insoluble DF is associated with lower prevalence of newly-diagnosed NAFLD in men. Moreover, intake DF from whole grain, soy foods, vegetables, and nuts, but not fruits have favorable effect on the prevalence of newly diagnosed NAFLD. Further cohort studies and randomized controlled trials are needed to validate this finding.

Mediterranean Diet and NAFLD: What We Know and Questions That Still Need to Be Answered

Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and is expected to become the leading cause of end-stage liver disease worldwide over the next few decades. In fact, NAFLD encompasses different clinical scenarios, from the simple accumulation of fat (steatosis) to steatohepatitis (NASH), NASH-cirrhosis, and cirrhosis complications. In this context, it is fundamental to pursue strategies aimed at both preventing the disease and reducing the progression of liver fibrosis once liver damage is already initiated. As of today, no pharmacological treatment has been approved for NAFLD/NASH, and the only recommended treatment of proven efficacy are life-style modifications, including diet and physical exercise pointing at weight loss of 5%–7%. Different dietetic approaches have been proposed in this setting, and in this review, we will discuss the evidence regarding the efficacy of the Mediterranean Diet as a treatment for NAFLD. In particular, we will report the effects on liver-related outcomes.

Dietary vitamin E and C intake is inversely associated with the severity of nonalcoholic fatty liver disease

BACKGROUND & AIMS

Although antioxidants have a protective potential in nonalcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH), there is limited evidence regarding the role of dietary intake of antioxidants. The aim was to test the association between dietary vitamins E and C intake and NAFLD, NASH and fibrosis markers.

METHODS

Cross-sectional study of a large cohort of subjects undergoing colonoscopy. The presence of NAFLD was evaluated by ultrasonography. The level of steatosis was defined using SteatoTest, moderate-severe NASH using new quantitative NashTest and borderline-significant fibrosis ≥ F1-F2 using FibroTest. Nutritional intake was measured by food frequency questionnaire (FFQ).

RESULTS

Overall, 789 subjects were included (52.6% men, age 58.83 ± 6.58 years), 714 had reliable FibroMax. Adjusting for BMI, dietary and lifestyle factors, the upper tertile of vitamin E intake/1000 Kcal was associated with lower odds of NASH (OR = 0.64, 0.43-0.94, P = 0.024). There was an inverse association between reaching the recommended vitamin E intake and NASH (OR = 0.48, 0.30-0.77, P = 0.002). The upper tertile of vitamin C intake/1000 Kcal was associated with lower odds of NAFLD and NASH (OR = 0.68, 0.47-0.99, P = 0.045; OR = 0.57, 0.38-0.84, P = 0.004, respectively). Both vitamins were related with the level of steatosis according to SteatoTest.

CONCLUSION

Vitamin E and C intake may be protective from NAFLD-related liver damage.

The relationship between dietary antioxidant intake and physical activity rate with nonalcoholic fatty liver disease (NAFLD): A case - Control study

INTRODUCTION

Although dietary intakes, especially micronutrients, can be associated with the severity of nonalcoholic fatty liver disease (NAFLD), investigations on the amount of vitamins and antioxidants consumption and their relationship with NAFLD are very limited and incomplete. Therefore, we decided to investigate the relationship between antioxidant compounds intake and physical activity rate with NAFLD.

METHODS

In this study, 200 patients with NAFLD for the case group and 400 healthy subjects for the control group were selected. Patients were diagnosed as NAFLD after giving blood tests and performing Ultrasonography by a radiology specialist. Dietary intakes were evaluated through a validated 168-items semi-quantitative food frequency questionnaire (FFQ). Physical activity rate was estimated by a validated short form of International Physical Activity Questionnaire (Short IPAQ).

RESULTS

The study population was between 20 and 60 years old and 46% of them were women. Weight, waist circumference, hip circumference, WHR, and BMI in the cases were higher than the controls. Physical activity comparisons showed that controls had higher physical activity rate than cases. Mean consumption of vitamins C, A, D and alpha-tocopherol in case group was less than the other group. After adjustment for all potential confounder, subjects who were in highest tertile of vitamin A intake -in comparison to those in the lowest tertile of intake-decreased risk of NAFLD (OR = 0.40, 95%CI: 0.30-0.55). The same finding was obtained for vitamin D; [Top category vs. bottom category of vitamin D of intake (OR = 0.35, 95%CI: 0.20-0.61)].

CONCLUSIONS

We found that more intakes of vitamins A and D are related to lower risk of NAFLD in this group of Iranian adults. Physical activity rate in cases was less than the controls. Further prospective studies are required to confirm causal association between antioxidant compounds intake and NAFLD.

Association between nut intake and non-alcoholic fatty liver disease risk: a retrospective case-control study in a sample of Chinese Han adults

OBJECTIVES

Nut consumption has been associated with a lower risk of type 2 diabetes, metabolic syndrome and insulin resistance. However, its effect on the risk of non-alcoholic fatty liver disease (NAFLD) is unknown. Therefore, we investigated the relationship between nut consumption and NAFLD risk.

SETTING AND PARTICIPANTS

We conducted a retrospective case-control study including 534 patients diagnosed with NAFLD and 534 controls matched by sex and age (±5 years) from the Affiliated Nanping First Hospital of Fujian Medical University in China.

MAIN OUTCOME MEASURES

Information on dietary intake was collected using a semiquantitative food frequency questionnaire and nut consumption was calculated. Nut consumption was categorised using quartiles based on the distribution of daily nut intake of the controls. Binary logistic regression models were used to estimate ORs and the 95% CIs for the association between nut consumption and NAFLD risk.

RESULTS

After adjusting for potential confounding variables, nut consumption was not associated with NAFLD risk in the overall sample. When the fully adjusted model was stratified by sex, a significant inverse association was found between high nut consumption and NAFLD only among the men in the highest quartile (OR=0.43; 95% CI 0.26 to 0.71; P_{trend =} 0.01). The inverse association of nut consumption with NAFLD risk in men remained significant after controlling for other known or suspected risk factors for NAFLD.

CONCLUSIONS

Diets with a higher intake of nuts may be associated with a decreased risk of NAFLD, particularly in men.

Association between nut consumption and non-alcoholic fatty liver disease in adults

BACKGROUND & AIMS

Increased nut consumption has been associated with reduced inflammation, insulin resistance, and oxidative stress. Although these factors are closely involved in the pathogenesis of non-alcoholic fatty liver disease (NAFLD), few studies have focused on the association between nut consumption and NAFLD in the general population. We aimed to investigate the association of nut consumption and NAFLD in an adult population.

METHODS

A total of 23 915 participants from Tianjin Chronic Low-Grade Systemic Inflammation and Health (TCLSIH) Cohort Study were included in this study. Information on dietary intake was collected using a validated food frequency questionnaire. Abdominal ultrasonography was done to diagnose NAFLD. Multivariable logistic regression was used to assess the association of nut consumption with NAFLD.

RESULTS

After adjusting for sociodemographic, medical, dietary, and lifestyle variables, the odds ratios (95% confidence interval) for NAFLD across categories of nut consumption were 1.00 (reference) for <1 time/week, 0.91 (0.82, 1.02) for 1 time/week, 0.88 (0.76, 1.02) for 2-3 times/week, and 0.80 (0.69, 0.92) for ≥4 times/week (P for trend < 0.01). These associations were attenuated but remained significant after further adjustment for blood lipids, glucose, and inflammation markers.

CONCLUSIONS

Higher nut consumption was significantly associated with lower prevalence of NAFLD. Further prospective studies and randomized trials are required to ascertain the causal association between nut consumption and NAFLD.

Mixed Nut Consumption May Improve Cardiovascular Disease Risk Factors in Overweight and Obese Adults

Emerging research indicates that nuts are a source of health-promoting compounds demonstrating cardioprotective benefits. However, most studies have assessed the effect of single nuts rather than a nut mixture. The objective of this study was, therefore, to examine the effect of mixed-nut consumption on cardiovascular disease (CVD) risk factors in overweight and obese adults. In a randomized, parallel-arm, controlled trial, 48 participants consumed isocaloric (250 kcal) amounts of pretzels or mixed-nuts. Body weight (BW) (p = 0.024), BMI (p = 0.043), and insulin levels (p = 0.032) were significantly lower in the nut group compared to the pretzel group. Mixed-nut consumption also significantly reduced glucose (p = 0.04) and insulin (p = 0.032) levels after 4 and 8 weeks compared to baseline, respectively. Lactate dehydrogenase of the nut group was significantly lower than the pretzel group (p = 0.002). No significant differences were detected between groups for triglycerides, LDL-C, and HDL-C. However, pretzel consumption increased triglycerides (p = 0.048) from 4 weeks to 8 weeks. Moreover, LDL-C increased (p = 0.038) while HDL-C transiently decreased (p = 0.044) from baseline to 4 weeks. No significant lipid changes were detected within the nut group. Our results suggest that supplementing the diet with mixed-nuts could improve CVD risk factors by improving BW and glucose regulation in comparison to a common carbohydrate-rich snack without promoting the negative effects on lipids detected with pretzels.

A Prospective Study of Nut Consumption and Risk of Primary Hepatocellular Carcinoma in the U.S. Women and Men

Although increasing evidence suggests a potential beneficial effect of nut consumption on various diseases, no epidemiologic study has yet examined the association between nut consumption and risk of hepatocellular carcinoma (HCC). We prospectively examined this association in 88,783 women from the Nurses' Health Study and 51,492 men from the Health Professionals Follow-up Study. Nut consumption was assessed every 4 years using validated food frequency questionnaires. Multivariable HRs and 95% confidence intervals (95% CI) were estimated using Cox proportional hazards regression models after adjusting for HCC risk factors. After an average of 27.9 years of follow-up, we identified a total of 162 incident HCC cases. Higher total nut consumption was not significantly associated with HCC risk (the highest vs. lowest tertile intake, HR, 0.84; 95% CI, 0.56-1.26). For the same comparison, higher tree nut consumption was associated with a lower HCC risk (HR, 0.64; 95% CI, 0.43-0.95). We found nonsignificant inverse associations with consumption of walnuts, peanuts, and peanut butter. Overall, nut consumption was not strongly associated with HCC risk. There was a suggestive inverse association with tree nut consumption. Future studies should carefully consider hepatitis B or C virus infections and examine these associations in other racial/ethnic groups.

Impact of Nutritional Changes on Nonalcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a major global health threat due to its growing incidence and prevalence. It is becoming the leading cause of liver disease in addition to its strong association with cardio-metabolic disease. Therefore, its prevention and treatment are of strong public interest. Therapeutic approaches emphasize lifestyle modifications including physical activity and the adoption of healthy eating habits that intend to mainly control body weight and cardio-metabolic risk factors associated with the metabolic syndrome. Lifestyle interventions may be reinforced by pharmacological treatment in advanced stages, though there is still no registered drug for the specific treatment of NAFLD. The purpose of this review is to assess the evidence available regarding the impact of dietary recommendations against NAFLD, highlighting the effect of macronutrient diet composition and dietary patterns in the management of NAFLD.

Pistachio Consumption Prevents and Improves Lipid Dysmetabolism by Reducing the Lipid Metabolizing Gene Expression in Diet-Induced Obese Mice

Pistachios contain beneficial substances such as unsaturated fatty acids, phytosterols, and polyphenols. In the present study, we investigated if pistachio consumption is able to prevent or to revert hyperglycemia, dyslipidemia, hepatic steatosis, and adipose tissue morphological alterations caused by high fat diet (HFD) in the mouse. Moreover, the impact of pistachio intake on the mRNA expression of peroxisome proliferator-activated receptor γ (PPAR-γ), fatty acid transport proteins (FAT-P), fatty acid synthase (FAS), stearoyl-CoA desaturase (SCD1), and sterol regulatory element-binding transcription factor-1c (SREBP-1c) in liver and adipose tissue was also analyzed. No change in body weight, food intake, and hyperglycemia was observed between mice consuming pistachios (HFD-P) and HFD mice. Pistachio intake was able to prevent but not to reverse HFD-induced hypertriglyceridemia. Cholesterol plasma levels, steatosis grading, body fat mass, and adipocyte size were significantly lower in HFD-P group compared to HFD in both prevention and reversal protocol. Pistachio-diet was able to prevent HFD-induced overexpression of PPAR-γ, FAS, and SCD1 in the liver and SREBP-1c, PPAR-γ, and FAT-P in adipose tissue. Similarly, HFD-P significantly ameliorated the expression levels of FAT-P and SCD1 in the liver and SREBP-1c, FAS, and SCD1 in adipose tissue of obese mice. The present study shows that pistachio consumption is able to prevent and to ameliorate obesity-related dysfunctions by positively modulating the expression of genes linked to lipid metabolism.

No association between fruits or vegetables and non-alcoholic fatty liver disease in middle-aged men and women

OBJECTIVE

It has been hypothesized that fruit and vegetable intake is inversely associated with non-alcoholic fatty liver (NAFLD). However, some studies have speculated that fruit intake might be positively associated with NAFLD owing to the fructose content of the fruit. This might cause consumers to hesitate consuming fruit. The aim of this study was to assess the association between fruit and vegetable consumption and NAFLD.

METHODS

This was a cross-sectional study of 977 men and 1467 women, 40 to 69 y of age without current liver disease other than NAFLD and who did not report excess alcohol intake (i.e., ≥30 g/d in men and ≥20 g/d in women). Dietary intake was assessed using a validated diet history questionnaire. NAFLD was diagnosed from abdominal ultrasonography results. The association between quartiles of fruit or vegetable consumption and NAFLD prevalence was assessed using logistic regression analysis, with lowest category as reference.

RESULTS

The prevalence of NAFLD was 34.9% in men and 11.7% in women. Adjusted for age and lifestyle factors, fruit intake was inversely associated with NAFLD in both sexes. However, these associations disappeared after further adjustment for body mass index. Consumption of total vegetables was not associated with NAFLD. In women, a linear inverse association was demonstrated between green and yellow vegetable intake and NAFLD in the final model (P_trend = 0.04), but odds ratios for any intake category did not reach significance.

CONCLUSIONS

No obesity-independent association was found between fruit or vegetable intake and NAFLD. According to the findings of this study, Japanese do not need to restrict fruit consumption to limit fructose intake as a means of preventing NAFLD.