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

Dietary fiber intake, genetic predisposition of gut microbiota, and the risk of metabolic dysfunction-associated steatotic liver disease

This study aimed to explore the association between dietary fiber intake and the risk of metabolic dysfunction-associated steatotic liver disease (MASLD), as well as liver fat content, while considering genetic predispositions of MASLD, gut microbial abundance, and butyrate levels. This study analyzed data from 190,276 participants in the UK Biobank. Dietary fiber intake was assessed using 24-h dietary recall. MASLD cases were diagnosed through hospital admission records and death registries, and liver fat content was measured via magnetic resonance imaging. The genetic predispositions of MASLD, gut microbial abundance, and butyrate levels were evaluated using single nucleotide polymorphisms. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95 % confidence intervals (CIs). Over a median follow-up of 10.49 years, 1423 MASLD cases were recorded. Elevated dietary fiber intake was associated with a reduced risk of MASLD (HR: 0.72; 95 % CI: 0.58, 0.90) and a lower level of liver fat content (β: -0.97; 95 % CI: -1.21, -0.73) (all P for trend <0.05). Restricted cubic spline analyses further confirmed the linear inverse associations between fiber intake and the risk of MASLD. Notably, the negative associations between dietary fiber intake and both MASLD and liver fat content were consistent across different genetic predispositions of gut microbial abundance and butyrate levels. Moreover, the inverse association between dietary fiber intake and liver fat was strengthened by high genetic susceptibility of MASLD and elevated body mass index (both P for interaction <0.05). Overall, increased dietary fiber consumption was associated with a lower MASLD risk and decreased liver fat content regardless of genetic predispositions of gut microbial abundance and butyrate levels.

Metabolic diseases in the East Asian populations

East Asian populations, which account for approximately 20% of the global population, have become central to the worldwide rise of metabolic diseases over the past few decades. The prevalence of metabolic disorders, including type 2 diabetes mellitus, hypertension and metabolic dysfunction-associated steatotic liver disease, has escalated sharply, contributing to a substantial burden of complications such as cardiovascular disease, chronic kidney disease, cancer and increased mortality. This concerning trend is primarily driven by a combination of genetic predisposition, unique fat distribution patterns and rapidly changing lifestyle factors, including urbanization and the adoption of Westernized dietary habits. Current advances in genomics, proteomics, metabolomics and microbiome research have provided new insights into the biological mechanisms that might contribute to the heightened susceptibility of East Asian populations to metabolic diseases. This Review synthesizes epidemiological data, risk factors and biomarkers to provide an overview of how metabolic diseases are reshaping public health in East Asia and offers insights into biological and societal drivers to guide effective, region-specific strategies.

Association of ultra-processed foods consumption with increased liver steatosis in U.S. adults

Background

Recent studies demonstrated a strong association between dietary habits and liver health, particularly in the development of steatosis and fibrosis. This study aimed to examine the impact of ultra-processed foods (UPFs) on liver health, focusing specifically on their influence on the risks of liver steatosis and fibrosis.

Methods

A cross-sectional analysis was conducted on 4,992 participants aged 18 years and older from the 2017-2020 National Health and Nutrition Examination Survey (NHANES). Dietary intake was assessed using one or two 24-h dietary recalls, and foods were categorized by their processing level using the NOVA classification system. UPFs consumption was measured in grams and divided into quartiles. Liver health was assessed using controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) via elastography, to evaluate steatosis and fibrosis, respectively. Linear regression models were applied to assess the relationship between UPFs consumption and liver outcomes, adjusting for sociodemographic (age, sex, ethnicity), lifestyle (alcohol consumption, physical activity), and biomedical factors (liver enzyme levels).

Results

Higher UPF intake was significantly associated with increased CAP values, indicating a higher risk of liver steatosis. While liver fibrosis, measured by LSM, was also associated with UPF consumption, this relationship did not reach statistical significance. Multivariate analysis showed that increased UPF consumption did not significantly affect LSM (p = 0.110) but was strongly associated with elevated CAP values (p = 0.009). In participants with fatty liver (CAP > 248 dB/m), the association between UPF intake and CAP remained significant (p = 0.020). Participants in the highest quartile of UPFs consumption (Q4) exhibited higher CAP values compared to those in the lowest quartile (Q1) (β = 1.22; 95% CI: 1.02, 1.47). Stratified analysis revealed that the association between UPF intake and CAP was more pronounced in obese individuals (HR = 1.08, 95% CI: 1.03-1.15, p = 0.022) and those with high waist circumference (HR = 1.06, 95% CI: 1.01-1.10, p = 0.032).

Conclusion

These results underscore the adverse impact of UPFs on liver health, particularly by increasing steatosis, while the connection with fibrosis remains less straightforward.

Early childhood adiposity, lifestyle and gut microbiome are linked to steatotic liver disease development in adolescents

BACKGROUND/OBJECTIVES

To examine the relationship between early childhood adiposity, adolescent lifestyles, gut microbiota and steatotic liver disease (SLD) development in adolescents using data from a prospective, longitudinal cohort study.

METHODS

We included 69 adolescents (14-17 years old) with SLD and 69 adolescents without SLD, matched for BMI-z scores, sex, and age, from the 13-year longitudinal cohort the "Growth and Obesity Cohort Study". Anthropometric data between the ages of 4 and 17 and lifestyle parameters (including diet and physical activity) at 14-17 years old were evaluated. Fecal samples were collected and microbiome composition and function were assessed using 16S ribosomal RNA amplicon sequencing.

RESULTS

Principal component analysis demonstrated dietary intake factors and childhood adiposity factors expanding the distribution variation between case and control groups, respectively. Lower odds of developing SLD during adolescence was associated with higher levels of daily fiber intake during adolescence (adjusted odds ratio = 0.91) and lower childhood adiposity (triceps skinfold at 5 years of age, suprailiac skinfold at 8 and 11 years of age, and waist-to-hip ratio at age 5-9 years). SLD was associated with a lower abundance of specific microbial species, such as Bacteroides vulgatus, which was higher in the control group compared to the case group (control/case abundance ratio = 18.71). B. vulgatus abundance also positively correlated with dietary fiber intake and inversely correlated with childhood adiposity.

CONCLUSIONS

Adiposity in early childhood and a low dietary fiber intake may contribute to the pathogenesis of SLD during adolescence, possibly through alterations to the intestinal microbiome; these findings could inform early disease markers and targets for intervention.

Impact of Dietary Fiber on Inflammation in Humans

Cohort studies consistently show that a high intake of cereal fiber and whole-grain products is associated with a decreased risk of type 2 diabetes (T2DM), cancer, and cardiovascular diseases. Similar findings are also reported for infectious and chronic inflammatory disorders. All these disorders are at least partially caused by inflammaging, a chronic state of inflammation associated with aging and Metabolic Syndrome. Surprisingly, insoluble (cereal) fiber intake consistently shows stronger protective associations with most long-term health outcomes than soluble fiber. Most humans consume soluble fiber mainly from sweet fruits, which usually come with high levels of sugar, counteracting the potentially beneficial effects of fiber. In both observational and interventional studies, high-fiber diets show a beneficial impact on inflammation, which can be attributed to a variety of nutrients apart from dietary fiber. These confounders need to be considered when evaluating the effects of fiber as part of complex dietary patterns. When assessing specific types of fiber, inulin and resistant starch clearly elicit anti-inflammatory short-term effects, while results for pectins, beta-glucans, or psyllium turn out to be less convincing. For insoluble fiber, promising but sparse data have been published so far. Hypotheses on putative mechanisms of anti-inflammatory fiber effects include a direct impact on immune cells (e.g., for pectin), fermentation to pleiotropic short-chain fatty acids (for fermentable fiber only), modulation of the gut microbiome towards higher levels of diversity, changes in bile acid metabolism, a differential release of gut hormones (such as the glucose-dependent insulinotropic peptide (GIP)), and an improvement of insulin resistance via the mTOR/S6K1 signaling cascade. Moreover, the contribution of phytate-mediated antioxidative and immune-modulatory means of action needs to be considered. In this review, we summarize the present knowledge on the impact of fiber-rich diets and dietary fiber on the human inflammatory system. However, given the huge heterogeneity of study designs, cohorts, interventions, and outcomes, definite conclusions on which fiber to recommend to whom cannot yet be drawn.

Effect of whole grain and fiber consumption on chronic liver diseases: a systematic review and meta-analysis

Objective: The aim of the present study was to conduct a meta-analysis of observational studies to explore the latest evidence on the influence of whole grain and fiber consumption on total chronic liver diseases. Methods: We searched the PubMed and Web of Science online databases and reference lists of eligible articles up to June, 2024. Results: The odds ratio (OR) between whole grain intake and total chronic liver disease risk was 0.90 (95% confidence interval (CI): 0.81 to 0.99, p < 0.001) and indicated an OR of 0.65 (95% CI: 0.57 to 0.74, p < 0.001) between fiber intake and total chronic liver disease risk when comparing the highest and lowest total intake, both indicating a significant negative correlation. Furthermore, subgroup analysis revealed that the protective effect of whole grains on chronic liver diseases was the most significant in cirrhosis (OR = 0.65; 95% CI: 0.57 to 0.74) and mortality (OR = 0.37; 95% CI: 0.29 to 0.47). Conclusion: Whole grain and fiber intake has a protective effect on the risk of chronic liver diseases.

Global burden of metabolic dysfunction-associated steatotic liver disease attributable to high fasting plasma glucose in 204 countries and territories from 1990 to 2021

Metabolic dysfunction-associated steatotic liver disease (MASLD) brings heavy clinical and economic burdens to patients worldwide. High fasting plasma glucose (HFPG) was proven to be an important modifiable risk factor. However, the global burden distribution of HFPG-attributable MASLD has not been fully studied. This study aimed to describe the epidemiological distribution and trends of the burden of HFPG-attributable MASLD worldwide. The data source was the 2021 Global Burden of Disease Study. Descriptive statistics were mainly conducted using disability-adjusted life years (DALYs) and deaths of HFPG-attributable MASLD from 1990 to 2021, as well as their age-standardized rates (ASRs) and population-attributable fractions. Subgroup analyses were conducted by region, age group, and sex. We found that 213.48 thousand DALYs and 10.02 thousand deaths in MASLD were attributable to HFPG worldwide in 2021, with an increase of 2.96 and 3.32 times compared with 1990, respectively. Over the past 32 years, age-standardized DALY rates (ASDRs) have fluctuated upward, reaching 2.45 per 100,000 people in 2021, with an increase of 81.21%. The ASDRs continued to rise in low, low-middle, and high social demographic index (SDI) regions, fluctuated upward at high levels in middle SDI regions, and were relatively low in high-middle SDI regions. People aged 50-69 accounted for the largest proportion of DALYs, while people over 70 had the largest increase of 3.73 times. Men had higher ASDRs, and the sex difference has been gradually expanding over the past 32 years, peaking at the age of 45-49. In conclusion, the burden of HFPG-attributable MASLD has continued to increase globally, with differences in geographical area, age, and sex distribution. HFPG, as a modifiable risk factor, should be given more importance. The implementation of targeted health intervention strategies is recommended for each country based on trends in the burden of HFPG-attributable MASLD.

Exploring the association between dietary fiber intake and hepatic steatosis: insights from NHANES

PURPOSE

The link between dietary fiber intake and Non-alcoholic fatty liver disease (NAFLD) is under exploration, yielding inconsistent findings. Considering the limitations of previous research and the significance of dietary fiber in hepatic steatosis, this study investigates the association between dietary fiber intake and Controlled Attenuation Parameter (CAP) among 5935 participants from the National Health and Nutrition Examination Survey (NHANES).

MATERIALS AND METHODS

Multivariable regression was used to evaluate the association between dietary fiber intake and CAP. Smoothed curve fitting and threshold effect analysis techniques were applied to illustrate non-linear relationships.

RESULTS

After adjusting for other variables, a negative correlation emerged between dietary fiber intake and CAP. Subgroup analysis by gender and race/ethnicity revealed a sustained negative association between dietary fiber intake and CAP among females and Whites. Additionally, an inverted U-shaped relationship was observed between dietary fiber intake and CAP among women and other race, with inflection points at 13.80 g/day and 33.45 g/day, respectively.

CONCLUSION

Our research indicates that in the majority of Americans, there is an inverse relationship between dietary fiber intake and hepatic steatosis. This relationship exhibits an inverted U-shaped curve in women and other race, with a threshold effect. The findings of this study hold potential significance for clinical nutrition interventions, personalized dietary guidance, and advancing research into the diet-disease mechanism relationship.

The gut-liver axis in fatty liver disease: role played by natural products

Fatty liver disease, a condition characterized by fatty degeneration of the liver, mainly classified as non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD), has become a leading cause of cirrhosis, liver cancer and death. The gut-liver axis is the bidirectional relationship between the gut and its microbiota and its liver. The liver can communicate with the gut through the bile ducts, while the portal vein transports the products of the gut flora to the liver. The intestinal flora and its metabolites directly and indirectly regulate hepatic gene expression, leading to an imbalance in the gut-liver axis and thus contributing to the development of liver disease. Utilizing natural products for the prevention and treatment of various metabolic diseases is a prevalent practice, and it is anticipated to represent the forthcoming trend in the development of drugs for combating NAFLD/ALD. This paper discusses the mechanism of the enterohepatic axis in fatty liver, summarizes the important role of plant metabolites in natural products in fatty liver treatment by regulating the enterohepatic axis, and provides a theoretical basis for the subsequent development of new drugs and clinical research.

Association between dietary carbohydrate to fiber ratio and metabolic dysfunction associated fatty liver disease in adults: evidence from the NHANES 2017-2020

This study aimed to explore the association of carbohydrate to fiber ratio (CFR) with metabolic dysfunction-associated fatty liver disease (MAFLD) in adults. In this study, data from the 2 cycles (2017-2018 and 2019-2020) of the NHANES were used. Univariate and multivariate weighted logistic regression analyses were applied to evaluate the association between CFR and MAFLD. Odds ratios (ORs) and 95% confidence levels (CIs) were estimated. Subgroup analysis was further performed in terms of gender, age and comorbidity (diabetes, hypertension). A total of 3180 individuals were included, with 1408 (44.28%) in the non-MAFLD group and 1772 (55.72%) in the MAFLD group. After adjusting different variables, a dietary fiber intake of 11.15-18.40 g was associated with significantly lower odds of MAFLD compared with a fiber intake < 11.15 g (OR = 0.71, 95% CI 0.54-0.93). In contrast to a dietary CFR < 12.58, a CFR > 19.91 was associated with significantly higher odds of MAFLD (OR = 1.57, 95% CI 1.09-2.27). Compared with females with a dietary CFR < 12.58, those with a CFR > 19.91 had significantly increased odds of MAFLD (OR = 1.87, 95% CI 1.29-2.73). Among individuals aged < 65 years, a dietary CFR > 19.91 was associated with higher odds of MAFLD than a dietary CFR < 12.58 (OR = 1.52, 95% CI 1.02-2.25). For participants without diabetes (OR = 1.79, 95% CI 1.26-2.54) or hypertension (OR = 1.93, 95% CI 1.02-3.65), a dietary CFR > 19.91 was associated with elevated odds of MAFLD than a CFR < 12.58. In summary, a higher CFR was associated with significantly greater odds of MAFLD, indicating the negative association between carbohydrate quality and MAFLD. The research would be conducive to metabolic dysfunction-associated fatty liver disease treatment.

Associations of Macronutrients Intake With MRI-determined Hepatic Fat Content, Hepatic Fibroinflammation, and NAFLD

CONTEXT

A healthy lifestyle is the cornerstone of management in nonalcoholic fatty liver disease (NAFLD). However, the associations between dietary macronutrient composition and different aspects of NAFLD pathology are unclear and dietary recommendations for NAFLD are lacking.

OBJECTIVE

This work aimed to evaluate the associations of dietary macronutrient composition with hepatic steatosis, hepatic fibroinflammation, and NAFLD.

METHODS

In this cross-sectional study, a total of 12 620 UK Biobank participants who completed both the dietary questionnaire and magnetic resonance imaging (MRI) examination were included in this study. Dietary consumption of macronutrient was self-reported and calculated. MRI-determined hepatic fat content, fibroinflammation, and NAFLD were estimated.

RESULTS

First, we found that saturated fatty acid (SFA) intake was associated with higher hepatic steatosis, fibroinflammation, and NAFLD prevalence. In contrast, higher fiber or protein intake was reversely correlated with hepatic steatosis and fibroinflammation. Interestingly, starch or sugar intake was significantly associated with hepatic fibroinflammation, whereas monounsaturated fatty acid (MUFA) intake was negatively correlated with hepatic fibroinflammation. Isocaloric analysis revealed that replacing SFA with sugar, fiber, or protein was significantly associated with a reduction in hepatic steatosis, while replacing starch, sugar, or SFA with protein or MUFA was significantly correlated with a decrease in hepatic fibroinflammation.

CONCLUSION

Overall, our results demonstrate that specific macronutrients are associated with different aspects of NAFLD, and specific dietary compositions should be recommended for distinct NAFLD-risk populations.

Dietary fiber intake and mortality among survivors of liver cirrhosis: A prospective cohort study

Background

Liver cirrhosis is associated with significant nutritional risks and poor survival rates. Little is known about the impact of dietary factors on metabolic complications and mortality from cirrhosis.

Aim

The present study investigated the potential associations between dietary fibers and the risk of cirrhosis-related mortality.

Methods

In this prospective study, 121 ambulatory cirrhotic patients with more than six months of cirrhosis diagnosis were followed-up for 4 years. Dietary intakes were assessed using a 168-item semi-quantitative validated food frequency questionnaire. Crude and multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated through cox proportional hazards regression models.

Results

Comparing the highest versus the lowest tertile, soluble and insoluble fiber intake was associated with 62% (HR = 0.38, 95% CI = 0.045-3.5, p trend = 0.047) and 73% (HR = 0.27, 95% CI = 0.06-1.2, p trend = 0.021) lower mortality risk, respectively, after full adjustment for potential confounders. Higher intakes of total fiber were inversely but non-significantly associated with mortality risk.

Conclusion

Comprehensive assessment of dietary fiber intake associations with cirrhosis-related mortality showed that higher intakes of soluble and insoluble fiber were significantly associated with reduced mortality risk.

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.

Dietary fiber intake and non-alcoholic fatty liver disease: The mediating role of obesity

Background and aims

Dietary pattern rich in fiber is negatively associated with the risk of non-alcoholic fatty liver disease (NAFLD). Meanwhile, obesity is a known predisposing factor for NAFLD. Nutrient-focused research can enhance the mechanistic understanding of dietary effects. We thus hypothesized that higher dietary fiber intake was associated with lower risk of NAFLD through the mediating role of obesity.

Methods

In this nationwide cross-sectional study, dietary fiber was surveyed using two 24-h recalls. NAFLD and clinically significant fibrosis (CSF) were determined by vibration-controlled transient elastography. Multivariable logistic and linear regression were applied to investigate the association of dietary fiber with NAFLD, CSF, and liver function parameters. We used counterfactual-based mediation analysis to estimate the direct and indirect effect of dietary fiber on NAFLD.

Results

Of the 3,974 participants, ~36.86% and 7.78% of participants were diagnosed with NAFLD and CSF. Compared with participants among the lowest tertile, the highest tertile of dietary fiber consumption was associated with lower odds of NAFLD (OR = 0.81; 95% CI: 0.66-0.98; P _overall = 0.019). Dietary fiber intake appeared to be linked with lower odds of CSF (OR _{Tertile3vs.Tertile1} = 0.81; 95% CI: 0.58-1.14; P _overall = 0.107). Mediation analysis showed that obesity fully mediated the association of dietary fiber with NAFLD. Dietary fiber was associated with improved hepatic parameters.

Conclusions

The findings indicated that increasing dietary fiber intake could confer a greater benefit to protect against NAFLD. Translating these findings regarding dietary fiber into dietary advice might be an attractive strategy for NAFLD prevention.

The role of cereal soluble fiber in the beneficial modulation of glycometabolic gastrointestinal hormones

According to cohort studies, cereal fiber, and whole-grain products might decrease risk for type 2 diabetes (T2DM), inflammatory processes, cancer, and cardiovascular diseases. These associations, mainly affect insoluble, but not soluble cereal fiber. In intervention studies, soluble fiber elicit anti-hyperglycemic and anti-inflammatory short-term effects, partially explained by fermentation to short-chain fatty acids, which acutely counteract insulin resistance and inflammation. ß-glucans lower cholesterol levels and possibly reduce liver fat. Long-term benefits are not yet shown, maybe caused by T2DM heterogeneity, as insulin resistance and fatty liver disease - the glycometabolic points of action of soluble cereal fiber - are not present in every patient. Thus, only some patients might be susceptive to fiber. Also, incretin action in response to fiber could be a relevant factor for variable effects. Thus, this review aims to summarize the current knowledge from human studies on the impact of soluble cereal fiber on glycometabolic gastrointestinal hormones. Effects on GLP-1 appear to be highly contradictory, while these fibers might lower GIP and ghrelin, and increase PYY and CCK. Even though previous results of specific trials support a glycometabolic benefit of soluble fiber, larger acute, and long-term mechanistic studies are needed in order to corroborate the results.

Inverse Association of Fruit and Vegetable Consumption with Nonalcoholic Fatty Liver Disease in Chinese Patients with Type 2 Diabetes Mellitus

We aimed to investigate the association of fruit and vegetable consumption with nonalcoholic fatty liver disease (NAFLD) in Chinese patients with type 2 diabetes mellitus (T2DM). This cross-sectional study included 2667 Chinese patients with T2DM aged 18 to 76 years from March 2017 to October 2021. Dietary intake was assessed using a food frequency questionnaire, and prevalent NAFLD was diagnosed with abdominal ultrasonography. High fruit−vegetable consumption was determined using ≥500 g/day consumption of both fruit and vegetable, and both fruit and vegetable consumption were divided into three categories of <200 g/day (low), 200−400 g/day (median) and >400 g (high). The primary outcome measurement was multivariate-adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for the prevalence of NAFLD in relation to the highest fruit and (or) vegetable intake compared with the lowest. Secondary analyses were conducted to assess the effects of either fruit or vegetable intake on the fatty liver index (FLI) using multivariable linear regressions. There were 1694 men and 973 women in this study, and 1445 (54.06%) participants had prevalent NAFLD. Patients with high fruit−vegetable intake had a lower prevalence of NAFLD than those with low fruit−vegetable intake (52.04% vs. 56.48%), but this difference was not statistically significant (p = 0.065). Vegetable intake had a significantly inverse association with NAFLD (OR: 0.68, 95% CI: 0.52−0.90), but this association was not pronounced with fruit intake (OR: 1.23, 95% CI: 0.89−1.69) or fruit−vegetable intake (OR: 0.90, 95% CI: 0.73−1.10). Additional analyses showed that an increase in vegetable intake was linearly associated with a significant reduction in FLI (β: −1.028, 95% CI: −1.836, −0.219). In conclusion, higher vegetable consumption was associated with lower odds of NAFLD in Chinese patients with T2DM, which suggested that increased vegetable intake might protect patients with diabetes against NAFLD.

Does Consumption of Ultra-Processed Foods Matter for Liver Health? Prospective Analysis among Older Adults with Metabolic Syndrome

Non-alcoholic fatty liver disease (NAFLD) includes a spectrum of liver alterations that can result in severe disease and even death. Consumption of ultra-processed foods (UPF) has been associated with obesity and related comorbidities. However, the link between UPF and NAFLD has not been sufficiently assessed. We aimed to investigate the prospective association between UPF consumption and liver health biomarkers. Methods: We followed for 1 year 5867 older participants with overweight/obesity and metabolic syndrome (MetS) from the PREDIMED-Plus trial. A validated 143-item semi-quantitative food frequency questionnaire was used to evaluate consumption of UPF at baseline, 6, and 12 months. The degree of processing for foods and beverages (g/day) was established according to the NOVA classification system. The non-invasive fatty liver index (FLI) and hepatic steatosis index (HSI) were used to evaluate liver health at three points in time. The associations between changes in UPF consumption (percentage of total daily dietary intake (g)) and liver biomarkers were assessed using mixed-effects linear models with repeated measurements. Results: In this cohort, UPF consumption at baseline was 8.19% (SD 6.95%) of total daily dietary intake in grams. In multivariable models, each 10% daily increment in UPF consumption in 1 year was associated with significantly greater FLI (β 1.60 points, 95% CI 1.24;1.96 points) and HSI (0.43, 0.29; 0.57) scores (all p-values < 0.001). These associations persisted statistically significant after adjusting for potential dietary confounders and NAFLD risk factors. Conclusions: A higher UPF consumption was associated with higher levels of NAFLD-related biomarkers in older adults with overweight/obesity and MetS.

Clinical Practice Guidelines of the Russian Scientific Liver Society, Russian Gastroenterological Association, Russian Association of Endocrinologists, Russian Association of Gerontologists and Geriatricians and National Society for Preventive Cardiology on Diagnosis and Treatment of Non-Alcoholic Liver Disease

Aim:present clinical guidelines, aimed at general practitioners, gastroenterologists, cardiologists, endocrinologists, comprise up-to-date methods of diagnosis and treatment of non-alcoholic fatty liver disease.Key points.Nonalcoholic fatty liver disease, the most wide-spread chronic liver disease, is characterized by accumulation of fat by more than 5 % of hepatocytes and presented by two histological forms: steatosis and nonalcoholic steatohepatitis. Clinical guidelines provide current views on pathogenesis of nonalcoholic fatty liver disease as a multisystem disease, methods of invasive and noninvasive diagnosis of steatosis and liver fibrosis, principles of nondrug treatment and pharmacotherapy of nonalcoholic fatty liver disease and associated conditions. Complications of nonalcoholic fatty liver disease include aggravation of cardiometabolic risks, development of hepatocellular cancer, progression of liver fibrosis to cirrhotic stage.Conclusion.Progression of liver disease can be avoided, cardiometabolic risks can be reduced and patients' prognosis — improved by the timely recognition of diagnosis of nonalcoholic fatty liver disease and associated comorbidities and competent multidisciplinary management of these patients.

Intrahepatic Fat Content and COVID-19 Lockdown in Adults with NAFLD and Metabolic Syndrome

Background: COVID-19 lockdowns had a significant impact on people’s health, triggering levels of anxiety, perceived stress, and changes in food and nutritional status. Objectives: To assess the changes in dietary habits, metabolic syndrome (MetS) and liver parameters before and after the COVID-19 lockdown according to changes in intrahepatic fat content in adults with non-alcoholic fatty liver disease (NAFLD) and MetS. Design: Pre- and post-lockdown observation of the COVID-19 lockdown on fifty-nine 40–60-year-old participants with MetS and NAFLD, in a parallel group, randomised experiment intended to treat NAFLD. Methods: Anthropometrics, liver and MetS biochemical parameters, intrahepatic fat content by abdominal magnetic resonance imaging, and dietary assessment using a validated 148-item Food Frequency Questionnaire were collected pre-COVID-19 lockdown and post-lockdown. Results: COVID-19 lockdown led to negative changes in the liver of patients with NAFLD and MetS, with weight gain and increases in glycemia, ALT and intrahepatic fat content post lockdown. Participants with worsened liver status had low consumption of fibre, cheese, nuts and coffee, and high consumption of sweets and pastries. Participants who improved liver status ameliorated ALT values, waist circumference, and intrahepatic fat content, assessed by magnetic resonance imaging post-lockdown. Conclusions: The maintenance of healthy lifestyle habits is vital, especially for populations with NAFLD and MetS, to reduce unhealthy lifestyle patterns displayed during lockdown.

The Impact of NAFLD on Hospitalization Outcomes in Patients With Inflammatory Bowel Diseases: Nationwide Analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is highly prevalent in patients with inflammatory bowel diseases (IBD). Yet, the impact of NAFLD on outcomes, along with the contribution of nonmetabolic factors to NAFLD development, is unclear. To investigate these topics, we conducted a nationwide study examining the impact of NAFLD on hospitalization outcomes in IBD patients after adjusting for metabolic factors.

METHODS

Patients with IBD-related hospitalizations were identified using the Nationwide Readmissions Database from 2016 to 2018. Inflammatory bowel disease patients with and without NAFLD were matched based on IBD type, age, sex, metabolic syndrome, and diabetes mellitus. Primary outcomes were IBD-related readmission, IBD-related surgery, and death. Secondary outcomes were length of stay (LOS) and cost of care (COC). The primary multivariable model adjusted for obesity, dyslipidemia, Charlson-Deyo comorbidity index, hospital characteristics, payer, patient income, and elective status of admissions.

RESULTS

Nonalcoholic fatty liver disease was associated with a higher risk of IBD-related readmission (adjusted hazard ratio, 1.90; P < .01) and death (adjusted hazard ratio, 2.73; P < .01), 0.71-day longer LOS (P < .01), and $7312 higher COC (P < .01) in those with Crohn's disease. Nonalcoholic fatty liver disease was also associated with a higher risk of IBD-related readmission (adjusted hazard ratio, 1.65; P < .01), 0.64-day longer LOS (P < .01), and $9392 (P < .01) higher COC, but there was no difference in death in those with UC. No differences in risk of IBD-related surgery were observed.

CONCLUSIONS

Nonalcoholic fatty liver disease is associated with worse hospitalization outcomes in IBD patients after adjusting for metabolic factors. These data suggest nonmetabolic factors may be implicated in the pathogenesis of NAFLD in IBD patients and may contribute to worsened clinical outcomes.

The National Consensus statement on the management of adult patients with non-alcoholic fatty liver disease and main comorbidities

The National Consensus was prepared with the participation of the National Medical Association for the Study of the Multimorbidity, Russian Scientific Liver Society, Russian Association of Endocrinologists, Russian Association of Gerontologists and Geriatricians, National Society for Preventive Cardiology, Professional Foundation for the Promotion of Medicine Fund PROFMEDFORUM. The aim of the multidisciplinary consensus is a detailed analysis of the course of non-alcoholic fatty liver disease (NAFLD) and the main associated conditions. The definition of NAFLD is given, its prevalence is described, methods for diagnosing its components such as steatosis, inflammation and fibrosis are described. The association of NAFLD with a number of cardio-metabolic diseases (arterial hypertension, atherosclerosis, thrombotic complications, type 2 diabetes mellitus (T2DM), obesity, dyslipidemia, etc.), chronic kidney disease (CKD) and the risk of developing hepatocellular cancer (HCC) were analyzed. The review of non-drug methods of treatment of NAFLD and modern opportunities of pharmacotherapy are presented. The possibilities of new molecules in the treatment of NAFLD are considered: agonists of nuclear receptors, antagonists of pro-inflammatory molecules, etc. The positive properties and disadvantages of currently used drugs (vitamin E, thiazolidinediones, etc.) are described. Special attention is paid to the multi-target ursodeoxycholic acid (UDCA) molecule in the complex treatment of NAFLD as a multifactorial disease. Its anti-inflammatory, anti-oxidant and cytoprotective properties, the ability to reduce steatosis an independent risk factor for the development of cardiovascular pathology, reduce inflammation and hepatic fibrosis through the modulation of autophagy are considered. The ability of UDCA to influence glucose and lipid homeostasis and to have an anticarcinogenic effect has been demonstrated. The Consensus statement has advanced provisions for practitioners to optimize the diagnosis and treatment of NAFLD and related common pathogenetic links of cardio-metabolic diseases.

Multi-omics integration reveals the hepatoprotective mechanisms of ursolic acid intake against chronic alcohol consumption

PURPOSE

Alcoholic liver disease (ALD) is a major health issue globally. In addition to pharmacotherapy, dietary support is also regarded as reliable strategy for ALD management. As a widely distributed natural constituent within edible plants, the present study aims to investigate the hepatoprotective effects of ursolic acid (UA) against ALD and also to deepen insights into the underlying targets and mechanisms comprehensively.

METHODS

The hepatoprotective activity of UA against chronic alcohol-induced liver injury was investigated on Lieber-DeCarli liquid diet-based mouse model. In-depth RNA-seq transcriptomics and TMT-based proteomics analyses were conducted in parallel. Data integration as well as bioinformatics analysis were also performed to unravel the targets and mechanisms associated with the hepatoprotective activity of UA intake against alcoholic liver injury comprehensively.

RESULTS

The serum biomarkers and pathological characteristics indicated the hepatoprotective effects of UA intake on alcoholic liver injury. 567 target genes and 377 target proteins related to the hepatoprotective activity of UA were identified in transcriptomics and proteomics analysis respectively, most of which were associated with function of cellular process, cell part and binding. After data integration, 56 co-regulated targets, including ADH4, CYP450 enzymes, NQO1, apolipoproteins, glutathione-S-transferase, etc. which were consistently modulated on both mRNA and protein levels were identified. These co-regulated targets were found to be correlated with 70 KEGG pathways led by carcinogenesis, retinol metabolism and CYP450 metabolism pathways.

CONCLUSION

UA intake ameliorated chronic alcohol-induced liver injury. Given the role of the co-regulated targets in ALD and the bioinformatics analysis results, CYP450-, glutathione and redox homeostasis-dependent antioxidation, promotion of lipid transport, and restoration of ethanol metabolic capacity are the potentially underlying mechanisms. This information will further deepen our insights into the hepatoprotective effects of UA-rich edible plants, and provide us valuable instruction for ALD management.

Optimal Dietary Intake Composition of Choline and Betaine Is Associated with Minimized Visceral Obesity-Related Hepatic Steatosis in a Case-Control Study

Few studies on humans have comprehensively evaluated the intake composition of methyl-donor nutrients (MDNs: choline, betaine, and folate) in relation to visceral obesity (VOB)-related hepatic steatosis (HS), the hallmark of non-alcoholic fatty liver diseases. In this case-control study, we recruited 105 patients with HS and 104 without HS (controls). HS was diagnosed through ultrasound examination. VOB was measured using a whole-body analyzer. MDN intake was assessed using a validated quantitative food frequency questionnaire. After adjustment for multiple HS risk factors, total choline intake was the most significant dietary determinant of HS in patients with VOB (Beta: -0.41, p = 0.01). Low intake of choline (<6.9 mg/kg body weight), betaine (<3.1 mg/kg body weight), and folate (<8.8 μg/kg body weight) predicted increased odds ratios (ORs) of VOB-related HS (choline: OR: 22, 95% confidence interval [CI]: 6.5-80; betaine: OR: 14, 95% CI: 4.4-50; and folate: OR: 19, 95% CI: 5.2-74). Combined high intake of choline and betaine, but not folate, was associated with an 81% reduction in VOB-related HS (OR: 0.19, 95% CI: 0.05-0.69). Our data suggest that the optimal intake of choline and betaine can minimize the risk of VOB-related HS in a threshold-dependent manner.

Associations of Nutritional, Lifestyle, and Metabolic Factors With Non-alcoholic Fatty Liver Disease: An Umbrella Review With More Than 380,000 Participants

Background & Aims: Nonalcoholic fatty liver disease (NAFLD) is the most common liver injury. We performed this umbrella review of meta-analyses to summarize the evidence on the associations of nutritional, lifestyle, and metabolic factors with NAFLD.

Methods: We searched the PubMed, Embase, and Web of Science databases from inception until July 2, 2020, to identify meta-analyses of observational studies which explored the associations of nutritional, lifestyle, and metabolic factors with NAFLD. Evidence levels were assessed using summary effect sizes, 95% prediction intervals, between-study heterogeneity, evidence of small-study effects, and evidence of excess significance bias for each meta-analysis. (No. of PROSPERO, CRD42020200124).

Results: Twenty two risk or protective factors from 10 published meta-analyses were included and studied. Three risk factors (sugar-sweetened beverage consumption, serum fetuin-A, and waist circumference) with highly suggestive levels of evidence and three risk factors (soft drink consumption, former smoking, and body mass index) with suggestive levels of evidence were identified. Only two protective factors (physical activity and serum vitamin D level [among adults in Western countries]) with suggestive levels of evidence were identified. Furthermore, other six risk factors and two protective factors with weak levels of evidence were identified.

Conclusions: We found varying levels of evidence of associations of nutritional, lifestyle, and metabolic factors and NAFLD. The results suggest that nutritional and lifestyle management should be considered as a major primary preventive strategy for NAFLD. Moreover, considering the low quality of included meta-analyses and limited area of research topics, future high-quality original studies and meta-analyses should be performed to study these associations.

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.

A review of non-alcoholic fatty liver disease in non-obese and lean individuals

Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of hepatic disorders. It represents a wide range of chronic liver diseases in patients with no history of significant alcohol consumption, starting with simple steatosis and progressing towards non-alcoholic steatohepatitis, cirrhosis, and ultimately hepatocellular carcinoma. NAFLD is usually associated with type 2 diabetes mellitus, dyslipidemia, metabolic syndrome, and obesity. This disease has mostly been studied in obese individuals; however, it has been widely reported and studied among the lean/non-obese population in recent years. The pathogenesis of NAFLD in non-obese patients is associated with various genetic predispositions, particularly a patatin-like phospholipase domain-containing protein 3 G allele polymorphism, which results in the accumulation of triglyceride in the liver and resistance to insulin. Additionally, dietary factors such as high fructose consumption seem to play a substantial role in the pathology of non-obese NAFLD. Although there is not enough evidence on the treatment of NAFLD in non-obese patients, the standard approach is to advise altering one's lifestyle in order to diminish visceral adiposity. Dietary modification, weight loss, and increased physical activity are highly recommended. We aimed to review and summarize the existing information on the prevalence, pathogenesis, genetic predispositions, diagnosis, and treatment of NAFLD in non-obese patients according to the latest literature.

Effects of Insoluble Cereal Fibre on Body Fat Distribution in the Optimal Fibre Trial

SCOPE

The Optimal Fibre Trial (OptiFiT) investigates metabolic effects of insoluble cereal fibre in subjects with impaired glucose tolerance (IGT), showing moderate glycemic and anti-inflammatory benefits, especially in subjects with an obesity-related phenotype. An OptiFiT sub-group is analysed for effects on body fat distribution.

METHODS AND RESULTS

180 participants with IGT receive a blinded, randomized supplementation with insoluble cereal fibre or placebo for 2 years. Once a year, all subjects undergo fasting blood sampling, oral glucose tolerance test, and anthropometric measurements. A subgroup (n=47) also received magnetic resonance imaging and spectroscopy for quantification of adipose tissue distribution and liver fat content. We compared MR, metabolic and inflammatory outcomes between fibre and placebo group metabolism and inflammation. Visceral and non-visceral fat, fasting glucose, HbA1c, fasting insulin, insulin resistance, and uric acid decrease only in the fibre group, mirroring effects of the entire cohort. However, after adjustment for weight loss, there are no significant between-group differences. There is a statistical trend for fibre-driven liver fat reduction in subjects with confirmed non-alcoholic fatty liver disease (NAFLD; n = 19).

CONCLUSIONS

Data and evidence on beneficial effects of insoluble cereal fibre on visceral and hepatic fatstorage is limited, but warrants further research. Targeted trials are required.

Plant-Based Foods and Their Bioactive Compounds on Fatty Liver Disease: Effects, Mechanisms, and Clinical Application

Fatty liver disease (FLD), including nonalcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (AFLD), is a serious chronic metabolic disease that affects a wide range of people. Lipid accumulation accompanied by oxidative stress and inflammation in the liver is the most important pathogenesis of FLD. The plant-based, high-fiber, and low-fat diet has been recommended to manage FLD for a long time. This review discusses the current state of the art into the effects, mechanisms, and clinical application of plant-based foods in NAFLD and AFLD, with highlighting related molecular mechanisms. Epidemiological evidence revealed that the consumption of several plant-based foods was beneficial to alleviating FLD. Further experimental studies found out that fruits, spices, teas, coffee, and other plants, as well as their bioactive compounds, such as resveratrol, anthocyanin, curcumin, and tea polyphenols, could alleviate FLD by ameliorating hepatic steatosis, oxidative stress, inflammation, gut dysbiosis, and apoptosis, as well as regulating autophagy and ethanol metabolism. More importantly, clinical trials confirmed the beneficial effects of plant-based foods on patients with fatty liver. However, several issues need to be further studied especially the safety and effective doses of plant-based foods and their bioactive compounds. Overall, certain plant-based foods are promising natural sources of bioactive compounds to prevent and alleviate fatty liver disease.

Dietary approaches to managing nonalcoholic fatty liver disease

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD), a multisystem, prevalent liver disease, can be managed with lifestyle interventions, including diet, given the lack of well-established pharmacologic therapies. This review explores the different dietary approaches that have been found effective in the management of NAFLD, offering a unique resource to healthcare professionals.

Association Between Dietary Fiber Intake and Non-alcoholic Fatty Liver Disease in Adults

Background: Evidence on the association of non-alcoholic fatty liver disease (NAFLD), a public health concern, with dietary fiber intake is inconsistent.

Objective: To investigate the relationship between dietary fiber intake from different sources and NAFLD risk in US adults.

Methods: Data were collected from the 2007–2014 National Health and Nutrition Examination Survey. NAFLD was defined as a United States Fatty Liver Index ≥30, and dietary fiber intake was assessed through two 24-h dietary recall interviews. Logistic regression and restricted cubic spline models were used to explore the relationship of dietary intakes of total, cereal, fruit, and vegetable fiber with NAFLD risk.

Results: A total of 6,613 participants, aged more than 20 years, were included in this study. After adjusting for multiple confounding factors, the odds ratios and 95% confidence intervals of NAFLD for the highest quartile vs. lowest quartile intakes of total, cereal, fruit, and vegetable fiber were 0.12 (0.08–0.16), 0.25 (0.19–0.33), 0.41 (0.33–0.52), and 0.42 (0.32–0.56), respectively. In stratified analyses by sex and age, statistically significant negative associations of dietary intakes of total, cereal, fruit, and vegetable fiber with NAFLD risk were observed in all participants. Dose-response analysis indicated a non-linear correlation between NAFLD risk and dietary intake of total fiber, whereas the relationship was linear for cereal, fruit, and vegetable fiber intakes.

Conclusion: Total, cereal, fruit, and vegetable fiber intakes exhibit negative correlations with NAFLD risk in the general adult population in the United States.

Complex Dietary Topologies in Non-alcoholic Fatty Liver Disease: A Network Science Analysis

Background and Aims: Previous studies have explored the associations between nutrition (food groups, nutrients, and dietary patterns) and the prevalence of non-alcoholic fatty liver disease. However, it remains unclear whether how foods are consumed together is associated with non-alcoholic fatty liver disease. The present study aims to construct dietary networks from network science and to explore the associations between complex dietary networks and non-alcoholic fatty liver disease. Methods: The present case-control study generated 2,043 multivariate matched controls for 2,043 newly diagnosed non-alcoholic fatty liver disease cases. Mutual information, which represents both linear and non-linear dependencies among food groups, was used to construct the network topologies. Results: The dietary topologies in the studied case and control groups were different despite the fact that only few food groups show differences in absolute intake. The dietary structure of the case group focused on two major components with more cohesion among food groups, while contrarily the control group had one major component with higher diversity of food groups. The dietary topology of the case group showed equality in connections among beneficial and detrimental food groups, whereas the control group focused more on healthier food choices. Conclusions: This study suggests how foods are consumed, besides the absolute intake, could be an important determinant of the occurrence of non-alcoholic fatty liver disease. A diverse diet that focuses on whole grain, tubers, and vegetables could yield beneficial effects regarding non-alcoholic fatty liver disease. Network science could offer a complementary tool in nutritional epidemiology.

Peroxisome Proliferator-Activated Receptors and Their Novel Ligands as Candidates for the Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a major health issue worldwide, frequently associated with obesity and type 2 diabetes. Steatosis is the initial stage of the disease, which is characterized by lipid accumulation in hepatocytes, which can progress to non-alcoholic steatohepatitis (NASH) with inflammation and various levels of fibrosis that further increase the risk of developing cirrhosis and hepatocellular carcinoma. The pathogenesis of NAFLD is influenced by interactions between genetic and environmental factors and involves several biological processes in multiple organs. No effective therapy is currently available for the treatment of NAFLD. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that regulate many functions that are disturbed in NAFLD, including glucose and lipid metabolism, as well as inflammation. Thus, they represent relevant clinical targets for NAFLD. In this review, we describe the determinants and mechanisms underlying the pathogenesis of NAFLD, its progression and complications, as well as the current therapeutic strategies that are employed. We also focus on the complementary and distinct roles of PPAR isotypes in many biological processes and on the effects of first-generation PPAR agonists. Finally, we review novel and safe PPAR agonists with improved efficacy and their potential use in the treatment of NAFLD.

The Molecular and Mechanistic Insights Based on Gut-Liver Axis: Nutritional Target for Non-Alcoholic Fatty Liver Disease (NAFLD) Improvement

Non-alcoholic fatty liver disease (NAFLD) is recognized as the most frequent classification of liver disease around the globe. Along with the sequencing technologies, gut microbiota has been regarded as a vital factor for the maintenance of human and animal health and the mediation of multiple diseases. The modulation of gut microbiota as a mechanism affecting the pathogenesis of NAFLD is becoming a growing area of concern. Recent advances in the communication between gut and hepatic tissue pave novel ways to better explain the molecular mechanisms regarding the pathological physiology of NAFLD. In this review, we recapitulate the current knowledge of the mechanisms correlated with the development and progression of NAFLD regulated by the gut microbiome and gut-liver axis, which may provide crucial therapeutic strategies for NAFLD. These mechanisms predominantly involve: (1) the alteration in gut microbiome profile; (2) the effects of components and metabolites from gut bacteria (e.g., lipopolysaccharides (LPS), trimethylamine-N-oxide (TMAO), and N,N,N-trimethyl-5-aminovaleric acid (TMAVA)); and (3) the impairment of intestinal barrier function and bile acid homeostasis. In particular, the prevention and therapy of NAFLD assisted by nutritional strategies are highlighted, including probiotics, functional oligosaccharides, dietary fibers, ω-3 polyunsaturated fatty acids, functional amino acids (L-tryptophan and L-glutamine), carotenoids, and polyphenols, based on the targets excavated from the gut-liver axis.