Investigation of anthropometric, biochemical and dietary parameters of obese children with and without non-alcoholic fatty liver disease

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.

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.

Dietary Regulation of Hepatic Triacylglycerol Content-the Role of Eucaloric Carbohydrate Restriction with Fat or Protein Replacement

Accumulation of hepatic triacylglycerol (TG) is highly associated with impaired whole-body insulin-glucose homeostasis and dyslipidemia. The summarized findings from human intervention studies investigating the effect of reduced dietary carbohydrate and increased fat intake (and in studies also increased protein) while maintaining energy intake at eucaloric requirements reveal a beneficial effect of carbohydrate reduction on hepatic TG content in obese individuals with steatosis and indices of insulin resistance. Evidence suggests that the reduction of hepatic TG content after reduced intake of carbohydrates and increased fat/protein intake in humans, results from regulation of fatty acid (FA) metabolism within the liver, with an increase in hepatic FA oxidation and ketogenesis, together with a concomitant downregulation of FA synthesis from de novo lipogenesis. The adaptations in hepatic metabolism may result from reduced intrahepatic monosaccharide and insulin availability, reduced glycolysis and increased FA availability when carbohydrate intake is reduced.

Prevalence and Related Factors for Non-alcoholic Fatty Liver Disease in Obese Students

Background: Non-alcoholic fatty liver disease (NAFLD) occurs with the pathological accumulation of fat in the liver and is one of the most common liver disorders worldwide among adults and even children. Obesity is a risk factor for NAFLD. Objectives: Considering the increasing prevalence of obesity in Iran and worldwide, this study was conducted to determine the prevalence of NAFLD and its related factors in overweight and obese students of schools in Tehran, Iran. Methods: This cross-sectional study was performed on 115 overweight and obese students [body mass index (BMI) ≥ 25] with an age range of 7 - 17 years. Eligible individuals were classified into two groups with and without NAFLD. Liver ultrasonography and measurement of serum parameters, including fasting blood sugar, lipid profile, and liver enzymes, were performed. Next, the demographic and anthropometric characteristics were compared between the two groups. Results: Out of 115 studied students, 71 subjects were boys (61.7%). The results showed that the mean BMI in patients with fatty liver was significantly higher than in individuals without fatty liver (P = 0.03). According to our findings, the mean total cholesterol in NAFLD patients was significantly higher than in the group without NAFLD (P = 0.008). The univariate logistic regression model results for measuring factors related to fatty liver in students showed a significant positive correlation between male gender, BMI, total cholesterol, aspartate aminotransferase, and alanine aminotransferase. Conclusions: NAFLD is a substantial problem in school children and correlates with elevated BMI. Therefore, the measurement of BMI can be used as a useful predictor and screening tool for NAFLD in school children.

Combination of the effect of ginger and anti-inflammatory diet on children with obesity with nonalcoholic fatty liver disease: A randomized clinical trial

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver disease in children. Following earlier reports on an increase in the prevalence of childhood obesity, NAFLD is now becoming increasingly common in children. Although no definitive cure exists, early management, early diagnosis, and treatment can reduce its complications. This study aims to determine the effectiveness of the combination of ginger and an anti-inflammatory diet (AID) in children with obesity on fatty liver management. This randomized clinical trial was conducted on 160 children with obesity aged 8-11 years, with a mean (SD) weight of 65.01 (9.67) kg, mean (SD) height of 139.87 (7.37) cm, and mean (SD) body mass index of 33.40 (5.59) kg/m2. The study duration was 12 weeks. Children were divided into four groups: ginger (G), AID, ginger plus an AID (GPA), and control. Ginger capsules comprised 1000 mg of ginger, whereas the AID comprised fruits and vegetables, fish, turkey, and chicken (without skin) with lean meat, omega-3 sources, nuts, legumes, probiotic products, and elimination of inflammatory food. Following the intervention, serum fasting blood sugar and high-sensitivity C-reactive protein levels were significantly decreased in the AID (p = .006 and .002, respectively), G (p = .04 and <.001, respectively), and GPA (p <.001 in both cases, respectively) groups. Further, in the G and GPA groups, there was a significant decrease in body mass index (p = .04 in both cases, respectively), waist circumference (p = .009 and .003, respectively), waist-to-height ratio (p = .02 and .005, respectively), alanine aminotransferase (p = .004 and <.001, respectively), total cholesterol (p = .0002 and .0001, respectively) and low-density lipoprotein-cholesterol (p < .001 and <.001, respectively). Eventually, serum aspartate aminotransferase was decreased (p < .001) and high-density lipoprotein-cholesterol (p = .03) was increased significantly in the GPA group. As a main finding of this study, hepatic steatosis significantly decreased in the G and GPA groups. Ginger supplementation can effectively improve NAFLD in children, and its effectiveness was further increased when combined with an AID.

Tactics with Prebiotics for the Treatment of Metabolic Dysfunction-Associated Fatty Liver Disease via the Improvement of Mitophagy

Mitophagy/autophagy plays a protective role in various forms of liver damage, by renovating cellular metabolism linking to sustain liver homeostasis. A characterized pathway for mitophagy is the phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1)/Parkin-dependent signaling pathway. In particular, PINK1-mediated mitophagy could play an indispensable role in improving the metabolic dysfunction-associated fatty liver disease (MAFLD) which could precede to steatohepatitis (NASH), fibrosis, and hepatocellular carcinoma. In addition, the PI3K/AKT/mTOR pathway might regulate the various characteristics of cellular homeostasis including energy metabolism, cell proliferation, and/or cell protection. Therefore, targeting mitophagy with the alteration of PI3K/AKT/mTOR or PINK1/Parkin-dependent signaling to eliminate impaired mitochondria might be an attractive strategy for the treatment of MAFLD. In particular, the efficacy of prebiotics for the treatment of MAFLD has been suggested to be useful via the modulation of the PI3K/AKT/mTOR/AMPK pathway. Additionally, several edible phytochemicals could activate mitophagy for the improvement of mitochondrial damages, which could also be a promising option to treat MAFLD with providing liver protection. Here, the potential therapeutics with several phytochemicals has been discussed for the treatment of MAFLD. Tactics with a viewpoint of prospective probiotics might contribute to the development of therapeutic interventions.

Nonalcoholic fatty liver disease in adolescents with phenylketonuria

OBJECTIVE

This study aimed to investigate non-alcoholic fatty liver disease (NAFLD) occurrence and factors associated with the disease in phenylketonuria (PKU) patients undergoing exclusive dietary treatment.

METHOD

This cross-sectional study included 101 adolescents 10 to < 20 years of age with PKU, who were undergoing exclusive dietary treatment and monitored since early diagnosis at a single reference service. Anthropometric and biochemical assessments were performed and food intake was documented, and an ultrasound diagnosis of NAFLD was established. Data were evaluated using the Student's t-test for continuous variables, the chi-square for categorical variables, and logistic regression using the Wald chi-squared test; differences with p < 0.05 were considered to be statistically significant.

RESULTS

NAFLD was detected in 26 (25.7%) teenagers. There was no difference in prevalence between the sexes or nutritional status. The final logistic regression model revealed low sensitivity (26.1%) and high specificity (94.7%). The specificity suggested a lower likelihood of NAFLD in older adolescents, in the presence of normal or high levels of alkaline phosphatase, lower carbohydrate intake, and adequate protein and lipid intake.

CONCLUSIONS

The prevalence of NAFLD in adolescents with PKU was higher than that found in healthy Brazilian adolescents and similar to that found in obese Brazilian children, suggesting a higher risk for NAFLD in patients with PKU treated exclusively by dietary modification.

Screening and interventions to prevent nonalcoholic fatty liver disease/nonalcoholic steatohepatitis-associated hepatocellular carcinoma

Liver cancer is the sixth most commonly diagnosed cancer worldwide, with hepatocellular carcinoma (HCC) comprising most cases. Besides hepatitis B and C viral infections, heavy alcohol use, and nonalcoholic steatohepatitis (NASH)-associated advanced fibrosis/cirrhosis, several other risk factors for HCC have been identified (i.e. old age, obesity, insulin resistance, type 2 diabetes). These might in fact partially explain the occurrence of HCC in non-cirrhotic patients without viral infection. HCC surveillance through effective screening programs is still an unmet need for many nonalcoholic fatty liver disease (NAFLD) patients, and identification of pre-cirrhotic individuals who progress to HCC represents a substantial challenge in clinical practice at the moment. Patients with NASH-cirrhosis should undergo systematic HCC surveillance, while this might be considered in patients with advanced fibrosis based on individual risk assessment. In this context, interventions that potentially prevent NAFLD/ NASH-associated HCC are needed. This paper provided an overview of evidence related to lifestyle changes (i.e. weight loss, physical exercise, adherence to healthy dietary patterns, intake of certain dietary components, etc.) and pharmacological interventions that might play a protective role by targeting the underlying causative factors and pathogenetic mechanisms. However, well-designed prospective studies specifically dedicated to NAFLD/NASH patients are still needed to clarify the relationship with HCC risk.

Pectin in Metabolic Liver Disease

Alterations in the composition of the gut microbiota (dysbiosis) are observed in nutritional liver diseases, including non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) and have been shown to be associated with the severity of both. Editing the composition of the microbiota by fecal microbiota transfer or by application of probiotics or prebiotics/fiber in rodent models and human proof-of-concept trials of NAFLD and ALD have demonstrated its possible contribution to reducing the progression of liver damage. In this review, we address the role of a soluble fiber, pectin, in reducing the development of liver injury in NAFLD and ALD through its impact on gut bacteria.

Macronutrient and Micronutrient Intake in Adolescents With Non-alcoholic Fatty Liver Disease: The Association With Disease Severity

OBJECTIVES

While dietary changes are recommended to treat pediatric non-alcoholic fatty liver disease (NAFLD), the role of specific nutrients in disease progression is unclear. The objective of this study is to (1) assess the macronutrient and micronutrient intake in adolescents with liver biopsy proven NAFLD [with and without non-alcoholic steatohepatitis (NASH)] and lean controls; (2) determine nutritional predictors of disease severity amongst these groups.

METHODS

Adolescents with biopsy-proven NAFLD and lean controls completed the Harvard Food Frequency Questionnaire.

RESULTS

Twenty-eight NAFLD and 15 lean controls were studied. NAFLD with (n = 20) and without NASH (n = 8) had similar total calorie, protein, fat, and carbohydrate intake. Subjects with NASH had higher total sugar (122.3 ± 48.3 vs 83.1 ± 38.8 g), glucose (24.3 ± 9.3 vs 15.2 ± 7.5 g), sucrose (42.3 ± 16.9 vs 28.8 ± 11.7 g), and fructose (29.4 ± 12.5 vs 18.1 ± 8.0 g) intake than those with NAFLD but without NASH ( P < 0.05). Both NAFLD groups had similar micronutrient intake. Alanine aminotransferase (ALT) correlated with total caloric intake ( ρ = 0.4; P = 0.04). Total carbohydrate calories correlated with a higher NAS summary score ( ρ = 0.38; P = 0.04) and lobular inflammation ( ρ = 0.50; P = 0.007). Percent calories from added sugar and glucose correlated with worsening NAS summary score ( ρ = 0.44, P = 0.02; ρ = 0.48, P = 0.009) and lobular inflammation ( ρ = 0.51, P = 0.006; ρ = 0.53, P = 0.004). Percent calories from fructose correlated with lobular inflammation ( ρ = 0.56; P = 0.002). Total daily calories, protein, fat, carbohydrate, and micronutrient intake were similar between NAFLD and lean controls.

CONCLUSIONS

NASH patients consume similar total calories, protein, and fat as those without NASH, but have significantly higher sugar intake. NAFLD and lean children, however, have similar macro/micronutrient intake. Histologic disease severity correlates with total carbohydrate and added sugar intake, supporting a role for simple sugar intake in NAFLD progression.

Associations of Nutrient Intake Changes During Childhood with Adolescent Hepatic Fat: The Exploring Perinatal Outcomes Among CHildren Study

OBJECTIVE

To examine associations of dietary changes from childhood to adolescence with adolescent hepatic fat and whether the PNPLA3 rs738409 risk allele, a strong genetic risk factor for hepatic fat, modifies associations.

STUDY DESIGN

Data were from 358 participants in the Exploring Perinatal Outcomes among CHildren (EPOCH) study, a longitudinal cohort in Colorado. Diet was assessed by food frequency questionnaire in childhood (approximately 10 years of age) and adolescence (approximately 16 years of age) and converted to nutrient densities. Hepatic fat was assessed in adolescence by magnetic resonance imaging. Linear regression was used to test associations of dietary changes from childhood to adolescence with adolescent hepatic fat.

RESULTS

Increases in fiber, vegetable protein, and polyunsaturated fat intake from childhood to adolescence were associated with lower adolescent hepatic fat, and increases in animal protein were associated with higher hepatic fat (β per 5-unit increase on log-hepatic fat: -0.12 [95% CI, -0.21 to -0.02] for ▵fiber; -0.26 [95% CI, -0.45 to -0.07] for ▵vegetable protein; -0.18 [95% CI, -0.35 to -0.02] for ▵polyunsaturated fat; 0.13 [95% CI, 0.04-0.22] for ▵animal protein). There was evidence of effect modification by PNPLA3 variant, whereby inverse associations of ▵fiber and ▵vegetable protein and positive associations of ▵saturated fat with adolescent hepatic fat were stronger in risk allele carriers. Most conclusions were similar after adjusting for obesity in adolescence, but associations of ▵saturated fat with hepatic fat were attenuated toward the null.

CONCLUSIONS

Our results suggest that nutrient intake changes between childhood and adolescence, particularly decreases in fiber and vegetable protein and increases in saturated fat intake, interact with the PNPLA3 variant to predict higher hepatic fat in adolescence, and may be targets for reducing hepatic fat in high-risk youth.

Diagnosis and Staging of Pediatric Non-Alcoholic Fatty Liver Disease: Is Classical Ultrasound the Answer?

The increased prevalence of non-alcoholic fatty liver disease (NAFLD) requires special attention in pediatric patients, as it manifests in them in a more severe and progressive way compared to adults. The implementation of the appropriate therapeutic interventions is determinant of the attempts to treat it. For that purpose, early diagnosis and staging of the disease is essential. The purpose of this review was to find and reveal the most appropriate diagnostic strategies and tools for diagnosis and staging of pediatric NAFLD/NASH based on their accuracy, safety and effectiveness. The methodology followed was that of the literature review. Particular emphasis was put on the recent bibliography. A comparative study of published articles about the diagnosis and management of pediatric NAFLD/NASH was also performed. In terms of diagnosis, the findings converged on the use of classical ultrasound. Ultrasound presented average sensitivity and specificity for diagnosing the disease in children, while in the adult population, sensitivity and specificity were significantly higher. Proton density fat fraction magnetic resonance imaging has been increasingly used for the diagnosis of steatosis in pediatric patients. Elastography is an effective tool for staging liver fibrosis and discriminating NASH from NAFLD in children. Even though liver biopsy is the gold standard, especially for NASH, it should be avoided for pediatric patients. Biochemical tests are less specific and less sensitive for the diagnosis of NAFLD, and some of them are of high cost. It seems that diagnostic imaging should be a first-line tool for the staging and monitoring pediatric NAFLD/NASH in order for appropriate interventions to be implanted in a timely way.

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 Free Sugar and Sugary Beverage Intake in Early Childhood and Adult NAFLD in a Population-Based UK Cohort

(1) Background: High sugar intake is prevalent among children and is associated with non-alcoholic fatty liver disease (NAFLD). The purpose of this study is to determine if a high intake of free sugars and sugary beverages (SB) in childhood is associated with NAFLD in adulthood; (2) Methods: At 24 years, 3095 participants were assessed for severe hepatic steatosis (controlled attenuation parameter >280 dB/m) and had dietary data collected via a food frequency questionnaire at age three years. Multiple logistic regression models adjusted for total energy intake, potential confounders, and a mediator (offspring body mass index (BMI) at 24 years); (3) Results: Per quintile increase of free sugar intake association with severe hepatic steatosis at 24 years after adjusting for total energy was odds ratio (OR):1.07 (95% CL: 0.99-1.17). Comparing the lowest vs. the highest free sugar consumers, the association was OR:1.28 (95% CL: 0.88-1.85) and 1.14 (0.72, 1.82) after full adjustment. The OR for high SB consumption (>2/day) compared to <1/day was 1.23 (95% CL: 0.82-1.84) and OR: 0.98 (95% CL: 0.60-1.60) after full adjustment; (4) Conclusions: High free sugar and SB intake at three years were positively but weakly associated with severe hepatic steatosis at 24 years. These associations were completely attenuated after adjusting for confounders and 24-year BMI.

Vitamin D Effect on Ultrasonography and Laboratory Indices and Biochemical Indicators in the Blood: an Interventional Study on 12 to 18-Year-Old Children with Fatty Liver

PURPOSE

The rising prevalence of childhood obesity in the past decades has caused non-alcoholic fatty liver disease (NAFLD) to become the most common cause of pediatric chronic liver disease worldwide. This study was aimed at determining the effect of vitamin D (Vit D) on ultrasonography and laboratory indices of NAFLD and some blood biochemical indicators in children.

METHODS

In this interventional study liver ultrasonography was performed in 200 children with overweight and obesity. A 108 had fatty liver among which 101 were randomly divided into two groups of study (n=51) and control (n=50). The study group was treated with Vit D, 50000 U once a week whereas the control group received placebo with the same dose and package, both for 12 weeks. At the end of the intervention lab tests and ultrasound study was performed once again to evaluate the response to treatment.

RESULTS

It was found out that Vit D supplementation improved the fatty liver grade in the study group. The mean changes in hemoglobin (Hb), uric acid, highdensity lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), insulin, albumin and alanine aminotransferase (ALT) was significantly higher in the study group compared to controls (p<0.05). After the intervention and means adjustment, a significant difference was obtained in HDL-C, insulin, LDL-C and homeostasis model assessment of insulin resistance (HOMA-IR) between the two groups.

CONCLUSION

Vit D supplementation in addition to improving the fatty liver grade in ultrasonography and increasing the blood Vit D level, increases the HDL and Hb level besides decreasing uric acid, LDL, HOMA-IR, insulin and ALT levels.

Epidemiology of nonalcoholic fatty liver disease in Europe: a systematic review and meta-analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the developed countries. The aim of this study was to evaluate the NAFLD prevalence in European adults and children/adolescents of the general population and specific subgroups.

METHOD

Search for all articles published between 01/1990-06/2019 reporting NAFLD prevalence from European countries.

RESULTS

Nineteen studies with adults and 9 with children/adolescents were included. Pooled NAFLD prevalence in adults was 26.9%, being higher in studies using ultrasonography (27.2%) or fatty liver index (FLI) (30.1%) than liver biochemical tests (19.1%) and without differences between Mediterranean and non-Mediterranean countries or publication periods. Pooled NAFLD prevalence was higher in men than women (32.8% vs. 19.6%) and in patients with than those without metabolic syndrome (75.3% vs. 17.9%) or any of its components (always P<0.01). Ultrasound and FLI performed equally in estimating NAFLD prevalence in most subgroups. A higher prevalence was reported using FLI in obese and in diabetic patients, whereas a higher prevalence was observed with ultrasound in non-obese patients and in individuals without metabolic syndrome. NAFLD prevalence was 2.7% in unselected and 31.6% in obese/overweight children/adolescents.

CONCLUSIONS

NAFLD prevalence exceeds 25% in European adults, being higher in those with metabolic syndrome component(s)-related comorbidities. It remains low in unselected NAFLD population, but increased in overweight/obese European children/adolescents, particularly from Mediterranean countries.

Changes in Liver Enzymes and Metabolic Profile in Adolescents with Fatty Liver following Exercise Interventions

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is the most frequent cause of chronic liver diseases in both adults and children with obesity. The aim of this study was to compare the changes in liver enzymes and metabolic profile in adolescents with fatty liver following selected school-based exercise (SBE) and high-intensity interval training (HIIT) interventions.

METHODS

In a semi-experimental study, 34 obese male adolescents with clinically defined NAFLD were divided into the HIIT (n=11, age=12.81±1.02 years, body mass index [BMI]=26.68 ±2.32 kg/m²), selected SBE (n=11, age=13.39±0.95 years, BMI=26.47±1.74 kg/m²), and control (n=12, age=13.14±1.49 years, BMI=26.45±2.21 kg/m²) groups. The ultrasonography NAFLD grade, peak oxygen uptake (VO_2peak), lipid profile, insulin resistance, and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of the participants were measured before and after the exercise interventions.

RESULTS

The BMI, waist-to-hip ratio, and body fat percentage of the participants decreased, and a significant increase in VO_2peak was observed after the intervention; however, the HIIT group showed a significant improvement compared with the SBE group (p<0.01). Significant reductions were observed in the levels of insulin resistance, triglyceride, total cholesterol, ALT, and AST in both groups, although high-density lipoprotein levels decreased only in the HIIT group (p<0.01). Further, a significant reduction in low-density lipoprotein level was observed in the training groups (p<0.01), but this decrease was not significant compared with the control group (p>0.01).

CONCLUSION

HIIT and SBE are equally effective in improving health parameters in obese children and adolescents.

Nutrients, Genetic Factors, and Their Interaction in Non-Alcoholic Fatty Liver Disease and Cardiovascular Disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in Western countries and expose patients to increased risk of hepatic and cardiovascular (CV) morbidity and mortality. Both environmental factors and genetic predisposition contribute to the risk. An inappropriate diet, rich in refined carbohydrates, especially fructose, and saturated fats, and poor in fibers, polyunsaturated fats, and vitamins is one of the main key factors, as well as the polymorphism of patatin-like phospholipase domain containing 3 (PNPLA3 gene) for NAFLD and the apolipoproteins and the peroxisome proliferator-activated receptor (PPAR) family for the cardiovascular damage. Beyond genetic influence, also epigenetics modifications are responsible for various clinical manifestations of both hepatic and CV disease. Interestingly, data are accumulating on the interplay between diet and genetic and epigenetic modifications, modulating pathogenetic pathways in NAFLD and CV disease. We report the main evidence from literature on the influence of both macro and micronutrients in NAFLD and CV damage and the role of genetics either alone or combined with diet in increasing the risk of developing both diseases. Understanding the interaction between metabolic alterations, genetics and diet are essential to treat the diseases and tailoring nutritional therapy to control NAFLD and CV risk.

Effects of Dietary and Lifestyle Interventions on Liver, Clinical and Metabolic Parameters in Children and Adolescents with Non-Alcoholic Fatty Liver Disease: A Systematic Review

Non-alcoholic fatty liver disease (NAFLD) affects 5.5–10.3% of children worldwide, while in obese individuals, it increases to almost 34%. Pediatric NAFLD is consistently associated with metabolic syndrome and insulin resistance. As no pharmacological agents exist for the treatment of NAFLD, lifestyle modifications remain the only therapy. However, as not all overweight/obese children have NAFLD, high-quality data, focused exclusively on NAFLD population are needed. Therefore, the present systematic review assessed the efficacy of lifestyle (diet or exercise) based on randomized controlled clinical trials (RCTs) on liver, anthropometric, glucose, and lipid parameters in children, with imaging or biopsy-proven NAFLD. In general, the results were inconclusive and therefore no specific recommendations could be drawn. In most studies, differences were derived from within group comparisons, which are known to be highly misleading. However, both low-carbohydrate and low-fat diets could benefit liver outcomes, as long as weight loss is achieved, but not necessary glucose and lipid parameters. No RCTs were found on exercise alone, as compared to no intervention on pediatric NAFLD. Concerning diet plus exercise interventions, all studies led to improvements in liver outcomes accompanied with weight loss. Resolution of NAFLD was found in considerably high percentages, while improvements were also seen in glucose but were modest in lipid parameters.

Serum visfatin level as a noninvasive marker for nonalcoholic fatty liver disease in children and adolescents with obesity: relation to transient elastography with controlled attenuation parameter

BACKGROUND

Obesity is associated with an increased risk of nonalcoholic fatty liver disease (NAFLD). Visfatin is an adipokine produced by visceral fat tissue and liver cells. Transient elastography with controlled attenuation parameter (CAP) noninvasively assesses liver fibrosis and steatosis.

AIM

To measure visfatin level in 80 children and adolescents with obesity as a potential biomarker for NAFLD and assess its relation to transient elastography.

METHODS

Abdominal ultrasound, liver stiffness and CAP measurements were performed for all patients. Fasting lipid profile, fasting blood glucose, insulin level, liver and kidney functions, coagulation profile and serum visfatin levels were assessed.

RESULTS

Among patients with obesity, 31 (38.8%) had NAFLD and 16 (20%) patients had elevated alanine aminotransferase (ALT), while 9 (11.2%) had both NAFLD and elevated ALT. Transient elastography showed that 12.5% had fibrosis stage F1, 2.5% had F2 and another 2.5% had F3 while none had F4. Using CAP, 23.8, 13.8 and 17.5% had S1, S2 and S3, respectively. Serum visfatin levels were significantly elevated in all patients compared with nonobese controls. Higher visfatin levels were found among patients with dyslipidemia, NAFLD, elevated ALT and steatosis defined by CAP. Serum visfatin was related to the degree of fibrosis and steatosis. Visfatin cutoff value 18 ng/mL could significantly detect the presence of NAFLD with 83.9% sensitivity and 81.4% specificity. Serum visfatin was positively correlated to BMI, waist circumference, waist/hip ratio, ALT, total cholesterol, liver stiffness and CAP.

CONCLUSIONS

Visfatin could be a promising serum biomarker for monitoring liver disease among pediatric patients with obesity.

Evidence-based clinical advice for nutrition and dietary weight loss strategies for the management of NAFLD and NASH

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide and affects approximately one third of adults in the United States. The disease is becoming a global epidemic as a result of the rising rates of obesity and metabolic disease. Emerging data suggest weight loss of ≥10% overall body weight is beneficial in resolving steatosis and reversing fibrosis. Prospective trials comparing various diets are limited by lack of sufficient power as well as pre- and post-treatment histopathology, and therefore no specific diet is recommended at this time. In this narrative review we examine the pathophysiology behind specific macronutrient components that can either promote or reverse NAFLD to help inform more specific dietary recommendations. Overall, the data supports reducing saturated fat, refined carbohydrates, and red and processed meats in the diet, and increasing the consumption of plant-based foods. Diets that incorporate these recommendations include plant-based diets such as the Dietary Approaches to Stop Hypertension, Mediterranean, vegetarian, and vegan diets.

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.

Dietary determinants of hepatic fat content and insulin resistance in overweight/obese children: a cross-sectional analysis of the Prevention of Diabetes in Kids (PREDIKID) study

Paediatric non-alcoholic fatty liver disease has increased in parallel with childhood obesity. Dietary habits, particularly products rich in sugars, may influence both hepatic fat and insulin resistance (homeostatic model assessment for insulin resistance (HOMA-IR)). The aim of the study was to examine the association of the consumption of foods and food components, dairy desserts and substitutes (DDS), sugar-sweetened beverages (SSB), as well as total and added sugars, with hepatic fat and HOMA-IR. Dietary intake (two non-consecutive 24 h-recalls), hepatic fat (MRI) and HOMA-IR were assessed in 110 overweight/obese children (10·6 (sd 1·1) years old). Linear regression analyses were used to examine the association of dietary intake with hepatic fat and HOMA-IR adjusted for potential confounders (sex, age, energy intake, maternal educational level, total and abdominal adiposity and sugar intake). The results showed that there was a negative association between cereal intake and hepatic fat (β=-0·197, P&lt;0·05). In contrast, both SSB consumption (β=0·217; P=0·028) and sugar in SSB (β=0·210, P=0·035), but not DDS or sugar in DDS or other dietary components, were positively associated with hepatic fat regardless of potential confounders including total sugar intake. In conclusion, cereal intake might decrease hepatic fat, whereas SSB consumption and its sugar content may increase the likelihood of having hepatic steatosis. Although these observations need to be confirmed using experimental evidence, these results suggest that healthy lifestyle intervention programs are needed to improve dietary habits as well as to increase the awareness of the detrimental effects of SSB consumption early in life.

In a pilot study, reduced fatty acid desaturase 1 function was associated with nonalcoholic fatty liver disease and response to treatment in children

BACKGROUND

FADS1 gene encodes delta 5 desaturase, a rate-limiting enzyme in the metabolism of n-3 and n-6 polyunsaturated fatty acids (PUFAs). Minor alleles of FADS1 locus polymorphisms are associated with reduced FADS1 expression and intra-hepatic fat accumulation. However, the relationship between FADS1 expression and pediatric nonalcoholic fatty liver disease (NAFLD) risk remains to be explored.

METHODS

We analyzed FADS1 transcription levels and their association with intra-hepatic fat and histology in children, and we performed pathway enrichment analysis on transcriptomic profiles associated with FADS1 polymorphisms. We also evaluated the weight of FADS1 alleles on the response to combined docosahexaenoic acid, choline, and vitamin E (DHA-CHO-VE) treatment.

RESULTS

FADS1 mRNA level was significantly and inversely associated with intra-hepatic fat (p = 0.004), degree of steatosis (p = 0.03), fibrosis (p = 0.05), and NASH (p = 0.008) among pediatric livers. Transcriptomics demonstrated a significant enrichment of a number of pathways strongly related to NAFLD (e.g., liver damage, fibrosis, and hepatic stellate cell activation). Compared to children who are common allele homozygotes, children with FADS1 minor alleles had a greater reduction in steatosis, fibrosis, and NAFLD activity score after DHA-CHO-VE.

CONCLUSION

This study suggests that decreased FADS1 expression may be associated with NAFLD in children but an increased response to DHA-CHO-VE.

Fructose metabolism, cardiometabolic risk, and the epidemic of coronary artery disease

Despite strong indications that increased consumption of added sugars correlates with greater risks of developing cardiometabolic syndrome (CMS) and cardiovascular disease (CVD), independent of the caloric intake, the worldwide sugar consumption remains high. In considering the negative health impact of overconsumption of dietary sugars, increased attention is recently being given to the role of the fructose component of high-sugar foods in driving CMS. The primary organs capable of metabolizing fructose include liver, small intestine, and kidneys. In these organs, fructose metabolism is initiated by ketohexokinase (KHK) isoform C of the central fructose-metabolizing enzyme KHK. Emerging data suggest that this tissue restriction of fructose metabolism can be rescinded in oxygen-deprived environments. In this review, we highlight recent progress in understanding how fructose metabolism contributes to the development of major systemic pathologies that cooperatively promote CMS and CVD, reference recent insights into microenvironmental control of fructose metabolism under stress conditions and discuss how this understanding is shaping preventive actions and therapeutic approaches.

Divergent effects of glucose and fructose on hepatic lipogenesis and insulin signaling

Overconsumption of high-fat diet (HFD) and sugar-sweetened beverages are risk factors for developing obesity, insulin resistance, and fatty liver disease. Here we have dissected mechanisms underlying this association using mice fed either chow or HFD with or without fructose- or glucose-supplemented water. In chow-fed mice, there was no major physiological difference between fructose and glucose supplementation. On the other hand, mice on HFD supplemented with fructose developed more pronounced obesity, glucose intolerance, and hepatomegaly as compared to glucose-supplemented HFD mice, despite similar caloric intake. Fructose and glucose supplementation also had distinct effects on expression of the lipogenic transcription factors ChREBP and SREBP1c. While both sugars increased ChREBP-β, fructose supplementation uniquely increased SREBP1c and downstream fatty acid synthesis genes, resulting in reduced liver insulin signaling. In contrast, glucose enhanced total ChREBP expression and triglyceride synthesis but was associated with improved hepatic insulin signaling. Metabolomic and RNA sequence analysis confirmed dichotomous effects of fructose and glucose supplementation on liver metabolism in spite of inducing similar hepatic lipid accumulation. Ketohexokinase, the first enzyme of fructose metabolism, was increased in fructose-fed mice and in obese humans with steatohepatitis. Knockdown of ketohexokinase in liver improved hepatic steatosis and glucose tolerance in fructose-supplemented mice. Thus, fructose is a component of dietary sugar that is distinctively associated with poor metabolic outcomes, whereas increased glucose intake may be protective.

Health and economic benefits of reducing sugar intake in the USA, including effects via non-alcoholic fatty liver disease: a microsimulation model

OBJECTIVES

Excessive consumption of added sugars in the human diet has been associated with obesity, type 2 diabetes (T2D), coronary heart disease (CHD) and other elements of the metabolic syndrome. Recent studies have shown that non-alcoholic fatty liver disease (NAFLD) is a critical pathway to metabolic syndrome. This model assesses the health and economic benefits of interventions aimed at reducing intake of added sugars.

METHODS

Using data from US National Health Surveys and current literature, we simulated an open cohort, for the period 2015-2035. We constructed a microsimulation model with Markov chains for NAFLD (including steatosis, non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma (HCC)), body mass index, T2D and CHD. We assessed reductions in population disease prevalence, disease-attributable disability-adjusted life years (DALYs) and costs, with interventions that reduce added sugars consumption by either 20% or 50%.

FINDINGS

The model estimated that a 20% reduction in added sugars intake will reduce prevalence of hepatic steatosis, NASH, cirrhosis, HCC, obesity, T2D and CHD. Incidence of T2D and CHD would be expected to decrease by 19.9 (95% CI 12.8 to 27.0) and 9.4 (95% CI 3.1 to 15.8) cases per 100 000 people after 20 years, respectively. A 20% reduction in consumption is also projected to annually avert 0.767 million (M) DALYs (95% CI 0.757M to 0.777M) and a total of US$10.3 billion (B) (95% CI 10.2B to 10.4B) in discounted direct medical costs by 2035. These effects increased proportionally when added sugars intake were reduced by 50%.

CONCLUSIONS

The decrease in incidence and prevalence of disease is similar to results in other models, but averted costs and DALYs were higher, mainly due to inclusion of NAFLD and CHD. The model suggests that efforts to reduce consumption of added sugars may result in significant public health and economic benefits.

Association of Blood Fatty Acid Composition and Dietary Pattern with the Risk of Non-Alcoholic Fatty Liver Disease in Patients Who Underwent Cholecystectomy

BACKGROUND/AIMS

The relationship between diet and non-alcoholic fatty liver disease (NAFLD) in patients with gallstone disease and in those who have a high risk for NAFLD has not been investigated. This study was conducted to investigate the association between the risk of NAFLD and dietary pattern in patients who underwent cholecystectomy. Additionally, we assessed the association between erythrocyte fatty acid composition, a marker for diet, and the risk of NAFLD.

METHODS

Patients (n = 139) underwent liver ultrasonography to determine the presence of NAFLD before laparoscopic cholecystectomy, reported dietary intake using food frequency questionnaire, and were assessed for blood fatty acid composition.

RESULTS

Fifty-eight patients were diagnosed with NAFLD. The risk of NAFLD was negatively associated with 2 dietary patterns: consuming whole grain and legumes and consuming fish, vegetables, and fruit. NAFLD was positively associated with the consumption of refined grain, meat, processed meat, and fried foods. Additionally, the risk of NAFLD was positively associated with erythrocyte levels of 16:0 and 18:2t, while it was negatively associated with 20:5n3, 22:5n3, and Omega-3 Index.

CONCLUSION

The risk of NAFLD was negatively associated with a healthy dietary pattern of consuming whole grains, legumes, vegetables, fish, and fruit and with an erythrocyte level of n-3 polyunsaturated fatty acids rich in fish.

Obese Children with Metabolic Syndrome Have 3 Times Higher Risk to Have Nonalcoholic Fatty Liver Disease Compared with Those without Metabolic Syndrome

BACKGROUND

The aim of this study was to investigate the relationship between metabolic syndrome (MS) and nonalcoholic fatty liver disease (NAFLD) in obese children. One hundred and twenty-five subjects aged 11-12 years old participated in the study.

METHODS

Anthropometric and biochemical indices were measured, including lipid and liver profile, blood glucose, serum insulin, and liver ultrasound.

RESULTS

Forty-four children (58.6%) were found to have MS. Insulin resistance was present in 78 (62.4%) children. Patients with MS were more likely to have NAFLD (P < 0.001). Children with NAFLD had significantly higher body mass index, waist circumference, triglycerides, fasting insulin, and lower high-density lipoprotein compared to patients with normal livers (P < 0.001). Insulin resistance was significantly higher in children with NAFLD (P < 0.001). Obese children presenting with MS were 3.01 (2.87-3.57, P < 0.002) times more likely to develop NAFLD compared to those without metabolic syndrome after adjustment of cofounders.

CONCLUSIONS

Obese children with MS have a higher risk of developing NAFLD. Weight management and early prevention should be the first line of treatment to prevent any possible health issues later on.

Non-alcoholic fatty liver disease (Nafld) in obese children- effect of refined carbohydrates in diet

Background

The incidence of childhood obesity has increased progressively and, associated with this, nonalcoholic fatty liver disease (NAFLD) has often been diagnosed in this age group. To determine the risk factors associated with NAFLD in obese children, with special emphasis on diet.

Methods

A prospective cross-sectional study was conducted with obese children referred to the endocrinology outpatient clinic. Questions about dietary habits and physical activity were applied. In addition, two 24 h food recalls were collected. Anthropometric measurements, biochemical tests and abdominal ultrasound were obtained. The study was approved by the institutional review board of Irmandade Santa Casa de Misericórdia de Porto Alegre Hospital (ISCMPA). A 5% statistical significance level was considered statistically significant.

Results

Of 55 patients initially allocated, 39 were evaluated and 8 (20.5%) had a diagnosis of NAFLD, which was more prevalent among boys (87.5%). Logistic regression analysis showed that the predictive factors independently associated with the presence of NAFLD were male gender (OR: 1.62; 95% CI: 1.08– 2.44; p = 0.038); high amount of refined carbohydrates in the diet (OR: 2.17; 95% CI: 1.05 – 6.82; p = 0.038) and absence of routine physical activity (OR: 3.35; 95% CI:1.97 – 0.006; p = 0.006).

Conclusions

The prevalence of NAFLD in obese children in our series was high. Furthermore, the high amount of refined carbohydrates in the diet, male gender and sedentary lifestyle were significant risk factors for its occurrence.

The effects of low carbohydrate diets on liver function tests in nonalcoholic fatty liver disease: A systematic review and meta-analysis of clinical trials

BACKGROUND

Although several observational and experimental studies have examined the effects of low carbohydrate diets (LCDs) on nonalcoholic fatty liver disease (NAFLD), there are considerable inconsistencies among studies. We summarized the effect of LCDs on liver function tests, including intrahepatic lipid content (IHLC), alanine transaminase (ALT), aspartate aminotransferases (AST), and gamma-glutamyl transferase (GGT) in patients with NAFLD.

MATERIALS AND METHODS

PubMed, ISI Web of Science, Scopus, and Google Scholar databases were searched for relevant publications until July 2014, resulting in ten relevant papers that were included in meta-analysis. Related articles were found by searching Medical Subject Heading terms of "NAFLD" in combination with "low carbohydrate". For this meta-analysis, we used mean differences and standard errors of liver function biomarkers. Summary effect and corresponding confidence interval (CI) were estimated using random effect models. Heterogeneity between studies was assessed using Cochran's Q- and I-squared tests.

RESULTS

Our search led to ten eligible papers that evaluated serum ALT levels (n = 238), nine reported serum AST levels (n = 216), five reported serum GGT concentrations (n = 91), and four assessed IHLC (n = 50). LCD decreased IHLC by -11.53% (95% CI: -18.10, -4.96; I2 = 83.2%). However, the effect of LCD on liver enzymes was not significant. Mean differences for the effects of LCDs on ALT, AST, and GGT were -4.35 IU/L (95% CI: -12.91, 4.20; I2 = 87.9%), -1.44 IU/L (95% CI: -4.98, 2.10; I2 = 61.4%), and -7.85 IU/L (95% CI: -29.65, 13.96; I2 = 99.4%), respectively.

CONCLUSION

LCD consumption in subjects with NAFLD led to a significant reduction in IHLC, but did not significantly affect the concentration of liver enzymes.

Associations of Apolipoprotein A, High-Sensitivity C-Reactive Protein and Fasting Plasma Insulin in Obese Children With and Without Family History of Cardiovascular Disease

BACKGROUND

The worldwide prevalence of childhood obesity has increased from 4.2% to 6.7% during the last two decades. Pediatric obesity is a major health problem, which is dramatically increasing in Greece. A variety of inflammatory variables have been also found to associate with cardiometabolic (CV) risk in obese children. The purpose of this study was to identify and examine the effects of possible CV risk factors in obese and non-obese children with and without family history (FH) of cardiovascular disease (CVD).

METHODS

Sixty-eight (68) healthy children and adolescents aged 7 - 13 years participated in the study. Anthropometrical and biochemical indexes were obtained from all children as well as FH of CVD.

RESULTS

Systolic blood pressure (SBP), total cholesterol (TC), triglyceride (TG), high-sensitivity C-reactive protein (hsCRP), fasting plasma insulin (FPI) and homeostasis model assessment of insulin resistance (HOMA-IR) levels were found statistically significantly higher in the obese group compared to the non-obese one. High-density lipoprotein (HDL) levels were observed to be statistically significantly lower in the obese children compared to their normal peers.

CONCLUSIONS

Apolipoprotein A, hsCRP and FPI levels were significantly higher in the obese children with FH of CVD compared to the ones without FH of CVD. TC and SBP were found to be independently associated with obesity (odds ratio (OR): 1.965, 95% confidence interval (CI): 1.935 - 2.97, P < 0.031 and OR: 1.045, 95% CI: 1.016 - 1.074, P < 0.002, respectively).

Role of Dietary Fructose and Hepatic De Novo Lipogenesis in Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a liver manifestation of metabolic syndrome. Overconsumption of high-fat diet (HFD) and increased intake of sugar-sweetened beverages are major risk factors for development of NAFLD. Today the most commonly consumed sugar is high fructose corn syrup. Hepatic lipids may be derived from dietary intake, esterification of plasma free fatty acids (FFA) or hepatic de novo lipogenesis (DNL). A central abnormality in NAFLD is enhanced DNL. Hepatic DNL is increased in individuals with NAFLD, while the contribution of dietary fat and plasma FFA to hepatic lipids is not significantly altered. The importance of DNL in NAFLD is further established in mouse studies with knockout of genes involved in this process. Dietary fructose increases levels of enzymes involved in DNL even more strongly than HFD. Several properties of fructose metabolism make it particularly lipogenic. Fructose is absorbed via portal vein and delivered to the liver in much higher concentrations as compared to other tissues. Fructose increases protein levels of all DNL enzymes during its conversion into triglycerides. Additionally, fructose supports lipogenesis in the setting of insulin resistance as fructose does not require insulin for its metabolism, and it directly stimulates SREBP1c, a major transcriptional regulator of DNL. Fructose also leads to ATP depletion and suppression of mitochondrial fatty acid oxidation, resulting in increased production of reactive oxygen species. Furthermore, fructose promotes ER stress and uric acid formation, additional insulin independent pathways leading to DNL. In summary, fructose metabolism supports DNL more strongly than HFD and hepatic DNL is a central abnormality in NAFLD. Disrupting fructose metabolism in the liver may provide a new therapeutic option for the treatment of NAFLD.

The relation of saturated fatty acids with low-grade inflammation and cardiovascular disease

The mantra that dietary (saturated) fat must be minimized to reduce cardiovascular disease (CVD) risk has dominated nutritional guidelines for decades. Parallel to decreasing intakes of fat and saturated fatty acids (SFA), there have been increases in carbohydrate and sugar intakes, overweight, obesity and type 2 diabetes mellitus. The "lipid hypothesis" coined the concept that fat, especially SFA, raises blood low-density lipoprotein-cholesterol and thereby CVD risk. In view of current controversies regarding their adequate intakes and effects, this review aims to summarize research regarding this heterogenic group of fatty acids and the mechanisms relating them to (chronic) systemic low-grade inflammation, insulin resistance, metabolic syndrome and notably CVD. The intimate relationship between inflammation and metabolism, including glucose, fat and cholesterol metabolism, revealed that the dyslipidemia in Western societies, notably increased triglycerides, "small dense" low-density lipoprotein and "dysfunctional" high-density lipoprotein, is influenced by many unfavorable lifestyle factors. Dietary SFA is only one of these, not necessarily the most important, in healthy, insulin-sensitive people. The environment provides us not only with many other proinflammatory stimuli than SFA but also with many antiinflammatory counterparts. Resolution of the conflict between our self-designed environment and ancient genome may rather rely on returning to the proinflammatory/antiinflammatory balance of the Paleolithic era in consonance with the 21st century culture. Accordingly, dietary guidelines might reconsider recommendations for SFA replacement and investigate diet in a broader context, together with nondietary lifestyle factors. This should be a clear priority, opposed to the reductionist approach of studying the effects of single nutrients, such as SFA.

Childhood energy intake is associated with nonalcoholic fatty liver disease in adolescents

BACKGROUND

Greater adiposity is an important risk factor for nonalcoholic fatty liver disease (NAFLD). Thus, it is likely that dietary intake is involved in the development of the disease. Prospective studies assessing the relation between childhood dietary intake and risk of NAFLD are lacking.

OBJECTIVE

This study was designed to explore associations between energy, carbohydrate, sugar, starch, protein, monounsaturated fat, polyunsaturated fat, saturated fat, and total fat intake by youth at ages 3, 7, and 13 y and subsequent (mean age: 17.8 y) ultrasound scan (USS)-measured liver fat and stiffness and serum alanine aminotransferase, aspartate aminotransferase, and γ-glutamyltransferase. We assessed whether observed associations were mediated through fat mass at the time of outcome assessment.

METHODS

Participants were from the Avon Longitudinal Study of Parents and Children. Trajectories of energy and macronutrient intake from ages 3-13 y were obtained with linear-spline multilevel models. Linear and logistic regression models examined whether energy intake and absolute and energy-adjusted macronutrient intake at ages 3, 7, and 13 y were associated with liver outcomes.

RESULTS

Energy intake at all ages was positively associated with liver outcomes; for example, the odds of having a USS-measured liver fat per 100 kcal increase in energy intake at age 3 y were 1.79 (95% CI: 1.14, 2.79). Associations between absolute macronutrient intake and liver outcomes were inconsistent and attenuated to the null after adjustment for total energy intake. The majority of associations attenuated to the null after adjustment for fat mass at the time liver outcomes were assessed.

CONCLUSION

Higher childhood and early adolescent energy intake is associated with greater NAFLD risk, and the macronutrients from which energy intake is derived are less important. These associations appear to be mediated, at least in part, by fat mass at the time of outcome assessment.

Changing beverage consumption patterns have resulted in fewer liquid calories in the diets of US children: National Health and Nutrition Examination Survey 2001-2010

BACKGROUND

Beverage consumption patterns have been linked to obesity and chronic disease risk. Although the consumption of sugar-sweetened beverages (SSBs) has decreased recently, little is known about the parallel trends in intake of other beverages.

OBJECTIVE

To describe recent trends in consumption of all commonly consumed beverages among US children aged 2 to 19 years.

DESIGN

Twenty-four-hour dietary recalls from 18,541 participants in the National Health and Nutrition Examination Survey from 2001-2010 were used to assess beverage intake, including SSBs (ie, sodas, fruit-flavored drinks, sport and energy drinks, fruit juices, coffees/teas, and other [nondairy] sugar-sweetened drinks); milks (ie, plain whole, reduced fat, and low-/nonfat, sweetened, other milks/milk-based drinks, and milk alternatives); 100% juices (ie, fruit, and vegetable/mixed without added sugar); low-/no-calorie beverages (ie, unsweetened or artificially sweetened: sodas, coffees/teas, flavored waters, diet sport/energy drinks, and other low/no-calorie drinks); alcohol-containing; and plain water (during 2005-2010 only). Weighted mean intakes (percent total energy and total ounces) and consumption prevalence were estimated. Regression models and analytical procedures that account for the complex sampling methods were used to test trends.

RESULTS

Between 2001-2002 and 2009-2010, total daily beverage consumption (excluding water) decreased from 24.4% to 21.1% energy (32.0 to 27.9 oz). Significant decreases (P<0.05) occurred in sugar-sweetened sodas (13.5% to 10.2% energy), whole milk (2.7% to 1.6% energy), fruit juices with sugar added (2.3% to 2.1% energy), and fruit-flavored drinks (1.6% to 0.8% energy). Significant increases occurred for sweetened coffees/teas, energy drinks, sport drinks, and unsweetened juices though the contribution of each to total energy intake remained <1%. Low-/no-calorie drink consumption also increased, rising from 0.2 to 1.3 oz/day.

CONCLUSIONS

Changing beverage consumption patterns reflect positive trends in the form of reduced intake of SSBs, whole milk, and total calories from beverages. Although the consumption of sport drinks, energy drinks, and low-calorie beverages have increased, their contribution to total beverage intake remains small.

PNPLA3 gene polymorphism accounts for fatty liver in community subjects without metabolic syndrome

BACKGROUND

The rs738409 GG variant in patatin-like phospholipase 3 (PNPLA3) is associated with non-alcoholic fatty liver disease (NAFLD) and disease severity. However, it remains unclear if it contributes to the development of NAFLD through affecting dietary pattern.

AIM

To examine the association among PNPLA3 gene polymorphism, dietary pattern, metabolic factors and NAFLD.

METHODS

Liver fat and fibrosis were assessed by proton-magnetic resonance spectroscopy and transient elastography in 920 subjects from a population screening project (251 had NAFLD). Dietary nutrient intake was recorded using a locally validated food-frequency questionnaire.

RESULTS

The prevalence of GG genotype in NAFLD subjects was 20.7%, compared to 10.6% in controls (P < 0.001). Macronutrient intake was similar among subjects with different PNPLA3 genotypes. The presence of G allele was a predictor of NAFLD independent of nutrient intake and other metabolic factors (adjusted odds ratio to CC: CG, 2.00; GG, 2.68). In subjects without metabolic syndrome, G allele was even more closely correlated with NAFLD diagnosis (adjusted odds ratio to CC: CG, 2.22; GG, 3.39). The prevalence of NAFLD was only 12% in subjects with CC genotype and no metabolic syndrome, and increased to 34% in those with GG genotype and no metabolic syndrome. While NAFLD subjects had significantly lower fibre intake, there was no significant interaction between PNPLA3 and dietary pattern.

CONCLUSIONS

The G allele in PNPLA3 rs738409 increases the risk of NAFLD in the general population, especially in subjects without metabolic syndrome, independent of dietary pattern and metabolic factors.

Nutrition, nonalcoholic fatty liver disease and the microbiome: recent progress in the field

PURPOSE OF REVIEW

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and it has overlapping pathogenesis with diabetes and cardiovascular disease. Reviewed here are recent advances in understanding the contribution of diet and selected nutrients to NAFLD.

RECENT FINDINGS

To understand the effect of diet, the microbiome must be considered because it is the interface of diet and the liver. Early studies suggest that the characteristic of the microbiota is altered in NAFLD. Fructose is a lipogenic carbohydrate that contributes to insulin resistance, hypertriglyceridemia and appears to be associated with the severity of NAFLD. Fructose absorption and malabsorption may alter the microbiota and could be mediating effects on the liver. Lipids also have potent microbiome interactions and could contribute to the benefit of diets emphasizing lipid changes. Several new studies demonstrate that the Mediterranean diet and 'lifestyle change' are effective in modestly improving NAFLD. A new study of 'lifestyle' in children showed simultaneous improvement in cardiovascular disease risk measurements and hepatic steatosis.

SUMMARY

Current data supports limiting sugar in the diet and 'lifestyle change' as a first-line treatment for NAFLD; however, the benefits from these appear to be modest. The effects of diet on the liver are mediated through the microbiome and expansion of research in this area is needed.

Dietary Quality Indices and Biochemical Parameters Among Patients With Non Alcoholic Fatty Liver Disease (NAFLD)

BACKGROUND

Dietary intake might have important role in non-alcoholic fatty liver diseases (NAFLD). Although, there are some reports on dietary intake and anthropometrics measurements, few studies have focused on the markers of assessing whole diet like dietary quality indices.

OBJECTIVES

Therefore, our aim was to determine the diet quality indices and biochemical parameters among patients with NAFLD and healthy individuals.

PATIENTS AND METHODS

This case-control study was performed on 100 patients with NAFLD and 100 healthy subjects who were attending to Gastrointestinal Research Center, Baqiyatallah University, Tehran, Iran during the recent years. Usual dietary intake was assessed by three dietary records (one weekend and two week days). Healthy eating index (HEI), dietary diversity score (DDS), dietary energy density (DED), mean adequacy ratio of nutrients (MAR) were assessed according to the standard methods.

RESULTS

Patients with NAFLD had higher body mass index, weight and waist circumference compared to the healthy group (P < 0.05). Serum levels of liver enzymes, triglyceride, LDL, BUN, and uric acid were higher in patients with NAFLD (P < 0.05). Although patients with NAFLD had higher energy, carbohydrate and fat intake, their values for antioxidant vitamins, calcium and vitamin D were lower than healthy subjects (P < 0.05). HEI and MAR were higher among healthy group, and DED was lower among them. Nutrient adequacy ratio for calcium, vitamin D, and antioxidant micronutrients were lower in patients with NAFLD (P < 0.05).

CONCLUSIONS

It seems that dietary quality indices may be associated with NAFLD. Calcium, vitamin D, and antioxidant micronutrients intake might be lower among patients with NAFLD based on this case-control study. Further prospective studies should be conducted in this regard.

Dietary fructose in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in adults and children. A number of genetic and environmental factors are known to predispose individuals to NAFLD. Certain dietary sugars, particularly fructose, are suspected to contribute to the development of NAFLD and its progression. The increasing quantity of fructose in the diet comes from sugar additives (most commonly sucrose and high fructose corn syrup) in beverages and processed foods. Substantial links have been demonstrated between increased fructose consumption and obesity, dyslipidemia, and insulin resistance. Growing evidence suggests that fructose contributes to the development and severity of NAFLD. In human studies, fructose is associated with increasing hepatic fat, inflammation, and possibly fibrosis. Whether fructose alone can cause NAFLD or if it serves only as a contributor when consumed excessively in the setting of insulin resistance, positive energy balance, and sedentary lifestyle is unknown. Sufficient evidence exists to support clinical recommendations that fructose intake be limited through decreasing foods and drinks high in added (fructose-containing) sugars.