Dietary isoflavones intake is inversely associated with non-alcoholic fatty liver disease, hyperlipidaemia and hypertension

Dietary isoflavone intake is inversely associated with remnant cholesterol in US adults: A cross-sectional study

BACKGROUND

Several studies have shown that dietary isoflavones are negatively correlated with total cholesterol and low-density lipoprotein cholesterol. However, few studies have investigated the link between dietary isoflavones and remnant cholesterol (RC).

OBJECTIVES

We used the National Health and Nutrition Examination Survey (NHANES) database to explore the association between dietary isoflavone intake and RC.

METHODS

A cross-sectional study was conducted with 4731 participants aged ≥ 20 years from the 2007-2008, 2009-2010, and 2017-2018 NHANES databases. We adopted univariate and multiple linear regression analysis and restricted cubic spline (RCS) to assess the relationship between dietary isoflavone intake and RC. Moreover, we conducted stratified and interaction analyses to ensure the stability of the results and identify specific populations.

RESULTS

The weighted multifactor linear regression model showed a negative correlation between dietary isoflavone intake and remnant cholesterol (Model 2, β = -0.049, 95% CI: (-0.096, -0.002), P = 0.040). The RCS analysis indicated that there was an L-shaped negative correlation between dietary isoflavone intake and RC (P-value for non-linearity was 0.0464). Stratified analyses showed the inverse relationship between dietary isoflavone intake and RC persisted in most subgroups and there was no interaction except for the recreational activity group.

CONCLUSIONS

Our study found a non-linear and negative association between dietary isoflavone intake and RC in US adults, so we hypothesized that consuming an isoflavone-rich diet may help reduce blood RC and further reduce the risk of cardiovascular disease.

The inverse associations of glycine and histidine in diet with hyperlipidemia and hypertension

BACKGROUND

Amino acids are crucial for nutrition and metabolism, regulating metabolic pathways and activities vital to organismal health and stability. Glycine and histidine act as potent antioxidants and anti-inflammatory agents; however, limited knowledge exists regarding the associations between these amino acids and hyperlipidemia and hypertension. The purpose of this study is to investigate the relationship between dietary glycine and histidine, and hyperlipidemia and hypertension.

METHODS

This population-based cross-sectional study evaluated the influence of dietary glycine and histidine, as well as their combined effect, on hyperlipidemia and hypertension in Chinese adults participating in the Nutrition Health Atlas Project (NHAP). General characteristics were acquired using a verified Internet-based Dietary Questionnaire for the Chinese. Binary logistic regression, along with gender, age groups, and median energy intake subgroup analyses, was employed to investigate the associations between dietary glycine and histidine and hyperlipidemia and hypertension. A sensitivity analysis was conducted to assess the impact of excluding individuals who smoke and consume alcohol on the results.

RESULTS

Based on the study's findings, 418 out of 1091 cases had hyperlipidemia, whereas 673 had hypertension. A significant inverse relationship was found between dietary glycine, histidine, and glycine + histidine and hyperlipidemia and hypertension. Compared with the 1st and 2nd tertiles, the multivariable-adjusted odd ratios (ORs) (95% confidence intervals) (CIs) of the 3rd tertile of dietary glycine for hyperlipidemia and hypertension were 0.64 (0.49-0.84) (p < 0.01) and 0.70 (0.56-0.88) (p < 0.001); histidine was 0.63 (0.49-0.82) (p < 0.01) and 0.80 (0.64-0.99) (p < 0.01); and glycine + histidine was 0.64 (0.49-0.83) (p < 0.01) and 0.74 (0.59-0.92) (p < 0.001), respectively. High glycine and high histidine (HGHH) intake were negatively associated with hyperlipidemia and hypertension OR (95% CIs) were: 0.71 (0.58-0.88) (p < 0.01) and 0.73 (0.61-0.87) (p < 0.01), respectively.

CONCLUSIONS

Dietary glycine and histidine, as well as their HGHH group, revealed an inverse relationship with hyperlipidemia and hypertension. Further investigations are needed to validate these findings.

Urinary Equol and Equol-Predicting Microbial Genera Are Favorably Associated with Body Fat Measures among Chinese Adults

BACKGROUND

Many studies have investigated the intake of dietary isoflavones in relation to obesity risk, whereas the association using objective biomarkers of isoflavones, particularly equol (a gut-derived metabolite of daidzein with greater bioavailability than other isoflavones) has been less studied. In addition, the associations between equol and gut microbiota profile at the population level remain to be fully characterized.

OBJECTIVES

We aimed to identify equol-predicting microbial species and to investigate the associations of equol-predicting microbial species and urinary excretion of isoflavones including glycitein, genistein, daidzein, and equol with diverse obesity markers in free living-individuals.

METHODS

In this 1-y longitudinal study of 754 community-dwelling adults, urinary isoflavones, fecal microbiota, height, weight, and circumferences of waist and hip were measured at baseline and again after 1 y. Liver fat [indicated by the controlled attenuation parameter (CAP)] and other body composition were also measured after 1 y. Linear models and linear mixed-effects models were used to analyze the associations for single measure and repeated measures, respectively.

RESULTS

Among 305 participants (median age: 50 y, IQR, 37-59 y) including 138 males and 167 females, higher urinary excretion of equol was associated with lower CAP (β = -0.013, P < 0.001) and body fat mass (β= -0.014, P = 0.046). No association was found between any other urinary isoflavones and obesity markers (all P > 0.05). We identified 21 bacterial genera whose relative abundance were positively associated with urinary equol concentrations (all Pfalsediscovery rate < 0.05), and constructed an equol-predicting microbial score to reflect the overall equol-producing potential of host gut microbiota. This score was inversely associated with CAP (β = -0.040, P = 0.011).

CONCLUSIONS

High urinary equol concentrations and equol-predicting microbial species could be favorably associated with liver fat and other obesity markers.

The effect of soy isoflavones supplementation on metabolic status in patients with non-alcoholic fatty liver disease: a randomized placebo controlled clinical trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) accounts as a crucial health concern with a huge burden on health and economic systems. The aim of this study is to evaluate the effect of soy isoflavones supplementation on metabolic status in patients with NAFLD.

METHODS

In this randomized clinical trial, 50 patients with NAFLD were randomly allocated to either soy isoflavone or placebo groups for 12 weeks. The soy isoflavone group took 100 mg/d soy isoflavone and the placebo group took the similar tablets containing starch. Anthropometric indices, blood lipids, glycemic parameters and blood pressure were measured at the beginning and at the end of the study.

RESULTS

At the end of week 12 the level of serum triglyceride (TG), low density lipoprotein (LDL) and total cholesterol (TC) was significantly decreased only in soy isoflavone group compared to baseline (P < 0.05). Although waist circumference (WC) decreased significantly in both groups after 12 weeks of intervention (P < 0.05), hip circumference (HC) decreased significantly only in soy isoflavone group (P = 0.001). No significant changes observed regarding high density lipoprotein (HDL) and blood pressure in both groups. At the end of the study, serum glucose level was significantly decreased in the placebo group compared to baseline (P = 0.047). No significant changes demonstrated in the soy isoflavone group in regard to glycemic parameters (P > 0.05).

CONCLUSIONS

This study revealed that soy isoflavones could significantly reduce TG, LDL TC, WC and HC in NAFLD patients.

TRIAL REGISTRATION

The Ethics committee of Ahvaz Jundishapur University of Medical Sciences approved the protocol of the present clinical research (IR.AJUMS.REC.1401.155). The study was in accordance with the Declaration of Helsinki. This study's registered number and date are IRCT20220801055597N1 and 20.09.2022, respectively at https://fa.irct.ir .

Perspective: Observational Studies Involving Low-Soy Intake Populations Have Limited Ability for Providing Insight into the Health Effects of Soybean Isoflavones

Isoflavones are naturally occurring plant compounds found in uniquely high amounts in soybeans and foods made from this legume. These soybean constituents have been proposed to exert several health benefits and as such they have been the subject of an enormous amount of research. This research includes randomized controlled trials (RCTs) and epidemiologic investigations. Although statistically significant associations between isoflavone intake and a wide range of health outcomes have been identified in cohorts involving low-isoflavone intake populations, we suggest that these associations are unlikely to have a causal basis because exposure is too low for isoflavones to exert physiologic effects. In cohorts involving predominantly non-Asian, non-vegetarian populations, the highest isoflavone intake category is typically ≤3 mg/d, an amount of isoflavones provided by ∼30 mL (2 tablespoons) of soymilk made from whole soybeans. In comparison, mean isoflavone intake in the upper intake categories in observational studies involving high-isoflavone intake populations is typically ≥50 mg/d. In RCTs, intervention doses of isoflavones typically range between 40 and 100 mg/d. Health professionals advising patients and clients about soy food and isoflavone intake need to be aware of the limitations of epidemiologic research involving low-isoflavone intake populations. Intake recommendations are best based on the results of RCTs using clinically relevant doses of isoflavones and epidemiologic studies involving populations for whom soy foods are a habitual part of the diet.

The Inverse Association Between Isoflavone Intake and Prevalence of Metabolic Syndrome: A Cross-Sectional Study from National Health and Nutrition Examination Survey

Objective: Metabolic syndrome (MetS) is a global disease burden that has resulted in 10 million people being affected by it, yet no new drugs have been approved for clinical treatment. Isoflavone may be able to stop the development of MetS or enhance its treatment. Therefore, we investigated the relationship between dietary intake of isoflavone and prevalence of MetS to find potentially effective treatments. Methods: We conducted a cross-sectional study using data from 8512 National Health and Nutrition Examination Survey (NHANES) participants from 2007 to 2010 and 2017 to 2018 and their associated isoflavone intake from the flavonoid database in the USDA Food and Nutrient Database for Dietary Studies (FNDDS). We investigated the relationship between MetS status and isoflavone intake by adjusting for confounding variables using multivariable logistic regression models. Results: In a multivariable-adjusted model, there was a negative association between isoflavone intake and the incidence of MetS (odds ratio for Q4 vs. Q1 was 0.66, 95% confidence interval = 0.51-0.86, P = 0.003, p for trend was <0.001). This inverse association remained robust across most subgroups, while nonsignificant interactions were tested between isoflavone intake and age, sex, ethnicity, economic status, body mass index, smoking status, alcohol consumption, and physical activity level (P values for interaction >0.05). Conclusions: We found that MetS prevalence decreased with increased isoflavone intake, suggesting that dietary patterns of soy food or supplement consumption may be a valuable strategy to reduce the disease burden and the prevalence of MetS.

Protective effect of phytoestrogens on nonalcoholic fatty liver disease in postmenopausal women

Non-alcoholic fatty liver disease (NAFLD) is a progressive metabolic disease characterized by hepatic steatosis, inflammation, and fibrosis that seriously endangers global public health. Epidemiological studies have shown that the incidence of non-alcoholic fatty liver disease in postmenopausal women has significantly increased. Studies have shown that estrogen deficiency is the main reason for this situation, and supplementing estrogen has become a new direction for preventing the occurrence of postmenopausal fatty liver. However, although classical estrogen replacement therapy can reduce the incidence of postmenopausal NAFLD, it has the risk of increasing stroke and cardiovascular diseases, so it is not suitable for the treatment of postmenopausal NAFLD. More and more recent studies have provided evidence that phytoestrogens are a promising method for the treatment of postmenopausal NAFLD. However, the mechanism of phytoestrogens in preventing and treating postmenopausal NAFLD is still unclear. This paper summarizes the clinical and basic research evidence of phytoestrogens and reviews the potential therapeutic effects of phytoestrogens in postmenopausal NAFLD from six angles: enhancing lipid metabolism in liver and adipose tissue, enhancing glucose metabolism, reducing oxidative stress, reducing the inflammatory response, regulating intestinal flora, and blocking liver fibrosis (Graphical Abstract).

Inverse association of daily fermented soybean paste (“Jang”) intake with metabolic syndrome risk, especially body fat and hypertension, in men of a large hospital-based cohort

Introduction

Jang is a fermented soybean paste containing salt and is traditionally used as a substitute for salt to enhance the flavor of foods in Korea. It has been speculated that regular consumption of Jang may lower the risk of metabolic syndrome (MetS). We hypothesized that Jang intake was associated with the risk of MetS and its components after adjusting for potential confounders, including sodium intake. The hypothesis was investigated according to gender in a large city hospital-based cohort (n = 58,701) in Korea.

Methods

Jang intake, calculated as the sum of the intakes of Chungkookjang, Doenjang, Doenjang soup, and Ssamjang (a mixture of Doenjang and Kochujang), was included in the semi-quantitative food frequency questionnaire (SQFFQ) administered to the cohort, and the daily Jang intake was estimated. The participants were categorized into low-Jang and high-Jang groups by 1.9 g daily Jang intake. MetS was defined according to 2005 revised United States National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) criteria modified for Asians.

Results

The participants in the low-Jang and high-Jang groups consumed an average of 0.63 g and 4.63 g Jang daily; their total sodium intake was about 1.91 and 2.58 g/day, respectively. The participants in the high-Jang group had higher energy, fiber, calcium, vitamin C, vitamin D, and potassium intake than those in the low-Jang group. After adjusting for covariates, the participants with the highest sodium intake (≥3.31 g/day) were positively associated with MetS risk in the quintiles of men and women. Among the MetS components, waist circumference, fat mass, and hypo-high-density lipoprotein (HDL)-cholesterolemia were positively associated with sodium intake in all participants and women. Unlike the association seen with sodium intake, Jang intake (≥1.9 g/day) was inversely associated with MetS components, including waist circumference, fat mass, serum glucose concentrations, and hypo-HDL-cholesterolemia in all participants and men, after adjusting for covariates including sodium intake.

Discussion

Substituting salt for Jang in cooking may be recommended to prevent and alleviate MetS incidence, and its efficacy for MetS risk was better in men than women. The results can be applied to sodium intake in Asian countries where salt is used to promote flavor.

Antioxidant and anti-inflammatory agents in chronic liver diseases: Molecular mechanisms and therapy

Chronic liver disease (CLD) is a continuous process that causes a reduction of liver function lasting more than six months. CLD includes alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), chronic viral infection, and autoimmune hepatitis, which can lead to liver fibrosis, cirrhosis, and cancer. Liver inflammation and oxidative stress are commonly associated with the development and progression of CLD. Molecular signaling pathways such as AMP-activated protein kinase (AMPK), C-Jun N-terminal kinase, and peroxisome proliferator-activated receptors (PPARs) are implicated in the pathogenesis of CLD. Therefore, antioxidant and anti-inflammatory agents from natural products are new potent therapies for ALD, NAFLD, and hepatocellular carcinoma (HCC). In this review, we summarize some powerful products that can be potential applied in all the stages of CLD, from ALD/NAFLD to HCC. The selected agents such as β-sitosterol, curcumin, genistein, and silymarin can regulate the activation of several important molecules, including AMPK, Farnesoid X receptor, nuclear factor erythroid 2-related factor-2, PPARs, phosphatidylinositol-3-kinase, and lysyl oxidase-like proteins. In addition, clinical trials are undergoing to evaluate their efficacy and safety.

Association between daidzein intake and metabolic associated fatty liver disease: A cross-sectional study from NHANES 2017-2018

Background

Metabolic associated fatty liver disease (MAFLD) has become the most common liver disease globally, yet no new drugs have been approved for clinical treatment. Therefore, we investigated the relationship between dietary intake of soy-derived daidzein and MAFLD, to find potentially effective treatments.

Methods

We conducted a cross-sectional study using data from 1,476 participants in National Health and Nutrition Examination Survey (NHANES) from 2017 to 2018 and their associated daidzein intake from the flavonoid database in the USDA Food and Nutrient Database for Dietary Studies (FNDDS). We investigated the relationship between MAFLD status, controlled attenuation parameter (CAP), AST/Platelet Ratio Index (APRI), Fibrosis-4 Index (FIB-4), liver stiffness measurement (LSM), nonalcoholic fatty liver disease (NAFLD) fibrosis score (NFS), hepatic steatosis index (HSI), fatty liver index (FLI), and daidzein intake by adjusting for confounding variables using binary logistic regression models and linear regression models.

Results

In the multivariable-adjusted model II, there was a negative association between daidzein intake and the incidence of MAFLD (OR for Q4 versus Q1 was 0.65, 95% confidence interval [CI] = 0.46-0.91, p = 0.0114, p for trend was 0.0190). CAP was also negatively associated with daidzein intake, β = -0.37, 95% CI: -0.63 to -0.12, p = 0.0046 in model II after adjusting for age, sex, race, marital status, education level, family income-to-poverty ratio (PIR), smoking, and alcohol consumption. Stratified by quartiles of daidzein intake, trend analysis of the relationship between daidzein intake and CAP remained significant (p for trend = 0.0054). In addition, we also found that HSI, FLI, and NFS were negatively correlated with daidzein intake. LSM was negatively related to daidzein intake but had no statistical significance. The correlation between APRI, FIB-4, and daidzein intake was not strong (although p < 0.05, β values were all 0).

Conclusion

We found that MAFLD prevalence, CAP, HSI, and FLI, all decreased with increased daidzein intake, suggesting that daidzein intake may improve hepatic steatosis. Therefore, dietary patterns of soy food or supplement consumption may be a valuable strategy to reduce the disease burden and the prevalence of MAFLD.

Association between flavonoid and subclasses intake and metabolic associated fatty liver disease in U.S. adults: Results from National Health and Nutrition Examination Survey 2017-2018

BACKGROUND

Metabolic associated fatty liver disease (MAFLD) formerly known as non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Flavonoid is considered a promising candidate for metabolic disease prevention although few studies have explored the relationship between flavonoid intake and MAFLD.

PURPOSE

To assess the relationship between flavonoid intake and MAFLD prevalence in the U.S. adult population.

MATERIALS AND METHODS

The data of this cross-sectional study was obtained from National Health and Nutrition Examination Survey (NHANES) and Food and Nutrient Database for Dietary Studies (FNDDS) 2017-2018. Flavonoid and subclasses intake was assessed by two 24h recalls. MAFLD was diagnosed according to the consensus definitions. Multivariate logistic regression model was performed to examine the association between flavonoid intake and MAFLD with adjustments for confounders.

RESULTS

A total of 4,431 participants were included in this cross-sectional analysis. MAFLD had a weighted prevalence of 41.93% and was not associated with total flavonoid intake. A higher anthocyanin and isoflavone intake, on the other hand, was associated with a lower prevalence of MAFLD. The protective effect of higher anthocyanin intake was significant among male, Non-Hispanic White, and Non-Hispanic Asia participants. Higher isoflavone intake was associated with a lower risk of MAFLD in participants of younger (age < 50), Non-Hispanic Black, Non-Hispanic Asia, and higher HEI-2015 scores compared with the lowest quartile of isoflavone intake. Stratified analysis showed that compared with the lowest quartile of anthocyanin intake, the effect of anthocyanin intake on MAFLD varied by racial groups (P _interaction = 0.02). A positive correlation existed between HDL and anthocyanidin intake (P = 0.03), whereas a negative correlation existed between FPG and isoflavone intake (P = 0.02).

CONCLUSION

MAFLD was adversely linked with flavonoid subclasses, anthocyanin and isoflavone. This modifiable lifestyle provides a potential opportunity to prevent MAFLD. These findings promote future research into the links and mechanisms between anthocyanin and isoflavone intake and MAFLD.

Associations of Urinary Phytoestrogen Concentrations with Nonalcoholic Fatty Liver Disease among Adults

Phytoestrogens can alleviate some pathological processes related to nonalcoholic fatty liver disease (NAFLD). However, there are limited and contradictory studies on the relationships between phytoestrogens (especially single phytoestrogen) and NAFLD. The purpose of this study was to explore the relationships between urinary phytoestrogen concentrations and NAFLD in American adults. This cross-sectional study used the data of the National Health and Nutrition Examination Survey from 1999 to 2010, and 2294 adults were finally enrolled in this study. The concentrations of phytoestrogens were measured in urine samples, and urinary phytoestrogens were divided into tertiles according to the concentration distributions. The diagnosis of NAFLD was determined by the United States fatty liver index. The main analysis used a multivariate logistic regression model. The fully adjusted models included gender, age, race, education, marriage, poverty, body mass index, waist circumference, smoking, diabetes, hypertension, total cholesterol, high-density lipoprotein cholesterol, triglycerides, and other five phytoestrogens. In the fully adjusted model, the urinary enterolactone (ENL) concentration was negatively correlated with NAFLD (OR of Tertile 3 : 0.48, 95% CI 0.25–0.94). When stratified by age and gender, the urinary ENL concentration was negatively correlated with NAFLD in males aged 40–59 years (OR of Tertile 3 : 0.08, 95% CI 0.01–0.82), while the urinary equol concentration was positively correlated with NAFLD in such population (OR of Tertile 3 : 4.27, 95% CI 1.02–17.85). In addition, a negative correlation between enterodiol (END) concentration and NAFLD was observed in males aged 60 years or over (OR of Tertile 2 : 0.18, 95% CI 0.05–0.69). Collectively, in middle-aged males, urinary ENL may be associated with a lower risk of NAFLD, while urinary equol may be related to a higher risk. In addition, urinary END has a possible relationship with a reduced risk of NAFLD in elder males. Definitely, clinical randomized controlled trials are needed to further verify the conclusions.

The Effect of Dietary Polyphenols on Vascular Health and Hypertension: Current Evidence and Mechanisms of Action

The aim of this review was to explore existing evidence from studies conducted on humans and summarize the mechanisms of action of dietary polyphenols on vascular health, blood pressure and hypertension. There is evidence that some polyphenol-rich foods, including berry fruits rich in anthocyanins, cocoa and green tea rich in flavan-3-ols, almonds and pistachios rich in hydroxycinnamic acids, and soy products rich in isoflavones, are able to improve blood pressure levels. A variety of mechanisms can elucidate the observed effects. Some limitations of the evidence, including variability of polyphenol content in plant-derived foods and human absorption, difficulty disentangling the effects of polyphenols from other dietary compounds, and discrepancy of doses between animal and human studies should be taken into account. While no single food counteracts hypertension, adopting a plant-based dietary pattern including a variety of polyphenol-rich foods is an advisable practice to improve blood pressure.

Potential Effects of Soy Isoflavones on the Prevention of Metabolic Syndrome

Isoflavones are polyphenols primarily contained in soybean. As phytoestrogens, isoflavones exert beneficial effects on various chronic diseases. Metabolic syndrome increases the risk of death due to arteriosclerosis in individuals with various pathological conditions, including obesity, hypertension, hyperglycemia, and dyslipidemia. Although the health benefits of soybean-derived isoflavones are widely known, their beneficial effects on the pathogenesis of metabolic syndrome are incompletely understood. This review aims to describe the association between soybean-derived isoflavone intake and the risk of metabolic syndrome development. We reviewed studies on soy isoflavones, particularly daidzein and genistein, and metabolic syndrome, using PubMed, ScienceDirect, and Web of Science. We describe the pathological characteristics of metabolic syndrome, including those contributing to multiple pathological conditions. Furthermore, we summarize the effects of soybean-derived daidzein and genistein on metabolic syndrome reported in human epidemiological studies and experiments using in vitro and in vivo models. In particular, we emphasize the role of soy isoflavones in metabolic syndrome-induced cardiovascular diseases. In conclusion, this review focuses on the potential of soy isoflavones to prevent metabolic syndrome by influencing the onset of hypertension, hyperglycemia, dyslipidemia, and arteriosclerosis and discusses the anti-inflammatory effects of isoflavones.