The effects of isoflavones combined with soy protein on lipid profiles, C-reactive protein and cardiovascular risk among postmenopausal Chinese women

Effect of Unfermented Soy Product Consumption on Blood Lipids in Postmenopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Clinical studies have reported the beneficial effects of unfermented soy product consumption on blood lipids in various populations. However, contradictory results have been reported regarding the influence of unfermented soy product consumption on blood lipids in postmenopausal women.

OBJECTIVE

The aim of this systematic review and meta-analysis was to evaluate the effects of diets with unfermented soy products compared with diets without unfermented soy products on blood lipids in postmenopausal women.

METHODS

The Cochrane Library, PubMed, Scopus, Web of Science, and Embase electronic databases were searched for eligible randomized controlled trials (RCTs) published up to February 21, 2023. RCTs were included if they were published in English and investigated the effect of unfermented soy product consumption on blood lipids in postmenopausal women who had discontinued hormone replacement therapy at least 3 months before randomization. A random-effects model was used to calculate the overall effect size of the mean difference (MD) and 95% CI. Risk of bias was assessed using the Cochrane Risk-of-Bias Tool for Randomized Trials, version 2.

RESULTS

Twenty-nine RCTs involving 2,457 participants were included. The results showed that, compared with the control group that did not consume unfermented soy products, consumption of unfermented soy products significantly reduced total cholesterol (TC) (MD, -9.46 mg/dL [to convert mg/dL cholesterol to mmol/L, multiply mg/dL by 0.0259; to convert mmol/L cholesterol to mg/dL, multiply by 38.7]; 95% CI -15.04 to -3.89 mg/dL; P = .001) and triglycerides (TGs) (MD, -10.86 mg/dL [to convert mg/dL TGs to mmol/L, multiply mg/dL by 0.0113; to convert mmol/L TGs to mg/dL, multiply mmol/L by 88.6]; 95% CI -19.70 to -2.02 mg/dL; P = .016), while significantly increasing high-density lipoprotein cholesterol (MD, 2.32 mg/dL; 95% CI 0.87 to 3.76 mg/dL; P = .002) in postmenopausal women, but had no significant effect on low-density lipoprotein cholesterol (MD, -4.55 mg/dL; 95% CI -10.90 to 1.80 mg/dL; P = .160). Results of soy preparation subgroup analysis showed that soy isolate protein significantly reduced TC and soy protein-containing isoflavones significantly reduced TC and low-density lipoprotein cholesterol and increased high-density lipoprotein cholesterol. Furthermore, unfermented soy product consumption significantly reduced TC, low-density lipoprotein cholesterol, and TG levels in postmenopausal women with lipid disorders and TGs in healthy postmenopausal women.

CONCLUSIONS

The results showed that unfermented soy product consumption reduced TC and TG levels significantly, and increased high-density lipoprotein cholesterol levels in postmenopausal women. The findings of this review contribute to the evidence-base for dietary management of blood lipids in postmenopausal women.

Effect of Isoflavones on Blood Lipid Alterations in Postmenopausal Females: A Systematic Review and Meta-Analysis of Randomized Trials

The effects of isoflavones on postmenopausal female's blood lipid profile have yielded conflicting results in previous studies. Further investigation is necessary to determine the potential benefits of isoflavone therapy in managing cardiovascular health in this population. This meta-analysis aimed to assess the effects of isoflavones on blood lipid concentrations in postmenopausal females. A comprehensive search was conducted in major databases for randomized controlled trials published between 2000 and 2023. Eighteen studies were included in the analysis, which examined the impact of isoflavone intake on blood lipids in postmenopausal females. Isoflavone consumption resulted in a significant reduction in triacylglycerol (TG) concentrations (-12.50 mg/dL; 95% CI: -23.09, -1.91) and a modest increase in high-density lipoprotein cholesterol (HDL cholesterol) concentrations (1.83 mg/dL; 95% CI: 0.03, 3.64). Subgroup analysis showed that isoflavones significantly decreased TG (-15.79 mg/dL; 95% CI: -28.36, -3.22) and increased HDL cholesterol (2.49 mg/dL; 95% CI: 1.80, 3.19) in postmenopausal females under 65 y old. No significant effects were observed in females over 65 y old. Both low (≤80 mg/d) and high (>80 mg/d) doses of isoflavones exhibited TG-lowering effects, whereas only the high dose increased HDL cholesterol. Longer treatment duration (≥24 wk) was associated with a significant reduction in TG, whereas HDL cholesterol improvement occurred during the early period (<24 wk) of supplementation. The consumption of isoflavones resulted in a significant reduction in TG concentrations and an increase in HDL cholesterol concentrations among postmenopausal females under 65 y of age.

Effect of soy isoflavones on C-reactive protein in chronic inflammatory disorders

New evidence suggests that soy products might reduce chronic systemic inflammation. Therefore, we aimed to summarize the effect of soy isoflavones on serum concentration of C-reactive protein (CRP) among participants with chronic inflammatory disorders by conducting this study. Cochrane Library, Scopus, ISI Web of Science, clinicaltrials.gov, and PubMed were searched to identify randomized clinical trials (RCTs) published up to December 2020. The effect size was calculated by the mean change from baseline in concentrations of CRP and its standard deviation for both intervention and comparison groups. DerSimonian and Laird random-effects model was used when the heterogeneity test was statistically significant. In total, thirteen RCTs involving 1213 participants and ten RCTs involving 1052 participants were eligible for our systematic review and meta-analysis respectively. Study duration ranged from 4 to 96 weeks and soy isoflavones dose varied from 33 to 132 mg/day. Overall effect size indicated a non-significant effect on serum concentration of CRP following soy isoflavones intake (weighted mean differences (WMD)=-0.15 mg/L, 95% confidence interval (CI): -0.54, 0.23; p=0.430). Subgroup analysis revealed that soy isoflavones significantly reduced serum concentration of CRP in studies among participants with age >57 years and baseline CRP levels >3.75 mg/L. The present study proposed that soy isoflavones could not significantly reduce serum CRP levels. It seems more RCTs on participants with age more than 57 years and higher levels of CRP is necessary.

Effects of whey and soy protein supplementation on inflammatory cytokines in older adults: a systematic review and meta-analysis

BACKGROUND AND AIMS

Low-grade inflammation is a mediator of muscle proteostasis. This study aimed to investigate the effects of isolated whey and soy proteins on inflammatory markers.

METHODS

We conducted a systematic literature search of randomised controlled trials (RCT) through MEDLINE, Web of Science, Scopus and Cochrane Library databases from inception until September 2021. To determine the effectiveness of isolated proteins on circulating levels of C-reactive protein (CRP), IL-6 and TNF-α, a meta-analysis using a random-effects model was used to calculate the pooled effects (CRD42021252603).

RESULTS

Thirty-one RCT met the inclusion criteria and were included in the systematic review and meta-analysis. A significant reduction of circulating IL-6 levels following whey protein [Mean Difference (MD): -0·79, 95 % CI: -1·15, -0·42, I² = 96 %] and TNF-α levels following soy protein supplementation (MD: -0·16, 95 % CI: -0·26, -0·05, I² = 68 %) was observed. The addition of soy isoflavones exerted a further decline in circulating TNF-α levels (MD: -0·20, 95 % CI: -0·31, -0·08, I² = 34 %). According to subgroup analysis, whey protein led to a statistically significant decrease in circulating IL-6 levels in individuals with sarcopenia and pre-frailty (MD: -0·98, 95 % CI: -1·56, -0·39, I² = 0 %). These findings may be dependent on participant characteristics and treatment duration.

CONCLUSIONS

These data support that whey and soy protein supplementation elicit anti-inflammatory effects by reducing circulating IL-6 and TNF-α levels, respectively. This effect may be enhanced by soy isoflavones and may be more prominent in individuals with sarcopenia.

Soy consumption and serum uric acid levels: A systematic review and meta-analysis

Background

Soy consumption has health benefits, but the relationship between soy and uric acid remains uncertain. This meta-analysis and systematic review evaluated the effects of soy intake on plasma uric acid.

Methods

PubMed, Embase, CNKI, and the Cochrane Library were searched for studies evaluating the effects of soy, soy products, soy protein, and soy isoflavones on uric acid levels. The primary outcome was serum or plasma uric acid concentration. Study quality was evaluated by the Cochrane Collaboration and SYRCLE risk-of-bias tools.

Results

A total of 17 studies were included. Qualitative analysis of three human clinical studies of acute effects revealed that soy consumption increased serum uric acid concentration; however, soy-derived products, including tofu, bean curd cake, and dried bean curd sticks, had no significant effect on serum uric acid. A meta-analysis of five long-term human studies (10 data sets) revealed that soy protein and soy isoflavones had no significant effects on uric acid levels [weighted mean difference (WMD) = -2.11; 95% confidence interval (CI): -8.78, 4.55; p = 0.53]. However, most epidemiological data revealed that soy intake is inversely associated with uric acid levels. Meta-analysis of nine animal trials (29 data sets) revealed that soy protein and soy isoflavones significantly reduced serum uric acid concentrations (vs. controls; MD = -38.02; 95% CI: -50.60, -25.44; p < 0.001).

Conclusion

Soy and its products have different effects on serum uric acid. Soy products like tofu, bean curd cake, and dried bean curd sticks could be high-quality protein sources for individuals with hyperuricemia or gout. It can be beneficial to nutritionists and healthcare decision-makers reconsider their conceptions about the relationship between soy and uric acid levels according to the latest and further scientific study results.

Systematic review registration

[www.crd.york.ac.uk/PROSPERO], identifier [CRD42022331855].

The health effects of soy: A reference guide for health professionals

Soy is a hotly debated and widely discussed topic in the field of nutrition. However, health practitioners may be ill-equipped to counsel clients and patients about the use of soyfoods because of the enormous, and often contradictory, amount of research that has been published over the past 30 years. As interest in plant-based diets increases, there will be increased pressure for practitioners to gain a working knowledge of this area. The purpose of this review is to provide concise literature summaries (400-500 words) along with a short perspective on the current state of knowledge of a wide range of topics related to soy, from the cholesterol-lowering effects of soy protein to the impact of isoflavones on breast cancer risk. In addition to the literature summaries, general background information on soyfoods, soy protein, and isoflavones is provided. This analysis can serve as a tool for health professionals to be used when discussing soyfoods with their clients and patients.

Role of Phytoestrogen-Rich Bioactive Substances (Linum usitatissimum L., Glycine max L., Trifolium pratense L.) in Cardiovascular Disease Prevention in Postmenopausal Women: A Systematic Review and Meta-Analysis

The aim of this report was to determine the impact of flaxseed, soy and red clover, and their bioactive substances on the lipid profile in postmenopausal women in cardiovascular diseases prevention. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Meta-analysis indicates that the intake of flaxseed by postmenopausal women is associated with a statistically significant reduction in total cholesterol (TC) levels (weighted-mean difference (WMD) = -0.26; 95% confidence interval (95% CI): -0.38 to -0.13; p = 0.0001), low-density lipoprotein cholesterol (LDL-C) levels (WMD = -0.19; 95% CI: -0.30 to -0.08; p = 0.0006), and high-density lipoprotein cholesterol (HDL-C) levels (WMD = -0.06; 95% CI: -0.11 to -0.01; p = 0.0150). The effect of soy protein on the lipid profile showed a significant decrease in TC levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0048, LDL-C levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0067, as well as a significant increase in HDL-C levels: WMD = 0.05; 95% CI: 0.02-0.08; p = 0.0034. Changes in the lipid profile showed a significant reduction in TC levels after the use of red clover (WMD = -0.11; 95% CI: -0.18--0.04; p = 0.0017) and a significant increase in HDL-C levels (WMD = 0.04; 95% CI: 0.01 to 0.07; p = 0.0165). This meta-analysis provides evidence that consuming flaxseed, soy and red clover can have a beneficial effect on lipids in postmenopausal women and suggest a favorable effect in preventing cardiovascular diseases.

A Meta-Analysis of Randomized Controlled Trials of the Effects of Soy Intake on Inflammatory Markers in Postmenopausal Women

BACKGROUND

Elevated concentrations of serum inflammatory cytokines, specifically TNF-α and IL-6, as well as C-reactive protein (CRP), are commonly observed after menopause.

OBJECTIVES

Because soy isoflavones may have some anti-inflammatory potential, the aim of the present systematic review and meta-analysis of randomized controlled trials (RCTs) was to explore whether soy intake affects serum markers of inflammation in postmenopausal women.

METHODS

PubMed, Web of Science, and the Cochrane Library were systematically searched up to August 2020. All RCTs that met the following criteria were included: 1) studies of the effects of soy intake on inflammatory markers; 2) any date of publication; 3) conducted on postmenopausal women; 4) with sufficient quantitative data for meta-analysis. Effect sizes were expressed as weighted mean differences (WMDs) and 95% CIs. A total of 24 RCTs assessing the effects of soy intake on serum concentrations of CRP, TNF-α, and IL-6 were included in the analysis. A random-effects model was used to determine the overall effect.

RESULTS

Soy supplementation significantly reduced CRP by 0.11 mg/L in postmenopausal women (95% CI: -0.22, -0.004 mg/L; P = 0.0414), but did not affect IL-6 or TNF-α. Significant reductions in CRP concentration occurred when natural soy products were given (WMD: -0.23 mg/L; 95% CI: -0.29, -0.17 mg/L; P < 0.001). This is equivalent to a ∼9% reduction in CRP concentration from baseline.

CONCLUSIONS

Although our meta-analysis found evidence that soy products significantly reduce CRP concentrations in postmenopausal women, the mechanisms by which soy foods and their constituents affect inflammatory biomarkers still need to be clarified.This systematic review was registered at www.crd.york.ac.uk/prospero/ as CRD42020179232.

The efficacy of soy isoflavones combined with soy protein on serum concentration of interleukin-6 and tumour necrosis factor-α among post-menopausal women? A systematic review and meta-analysis of randomized controlled trials

The post-menopausal stage in women's life is associated with the enhancement of inflammation that may be reduced using soy isoflavones or soy protein. The present study aimed to summarize the effect of soy isoflavones plus soy protein on circulating interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) in post-menopausal women. The English-language articles were identified from the databases such as Cochrane Library, clinicaltrials.gov, Web of Science, PubMed, and Scopus until December 2020. The mean change from baseline and its standard deviation (SD) for intervention and comparison groups were used to calculate the effect size. The statistical heterogeneity of the intervention effects was computing by Cochran's Q test and I² statistic. Nine and seven studies were selected for systematic review and meta-analysis, respectively. The results of our meta-analysis indicated a non-significant effect on the serum concentrations of IL-6 and TNF-α (weighted mean differences [WMD] = 0.07 pg/mL; 95% confidence interval [CI] = -0.03, 0.17 pg/mL; P = 0.190; WMD =0.05 pg/mL; 95% CI = -0.01, 0.12 pg/mL; P = 0.092; respectively). In subgroup analysis, soy isoflavones plus soy protein could increase the serum concentration of IL-6 in studies with soy isoflavones dose ≤87 mg/days, cross-over design, weak quality, and studies on participants who had health risk factors or diseases. The serum concentration of TNF-α increased in studies with cross-over design, intervention duration ≤56 days, and body mass index (BMI) >27, and in studies that were conducted on at-risk or sick participants. In conclusion, our meta-analysis did not confirm any significant effect on serum concentration of IL-6 and TNF-α among post-menopausal women.

Effects of Soy Protein Containing of Isoflavones and Isoflavones Extract on Plasma Lipid Profile in Postmenopausal Women as a Potential Prevention Factor in Cardiovascular Diseases: Systematic Review and Meta-Analysis of Randomized Controlled Trials

The aim of the report was to evaluate the impact of soy protein containing isoflavones and soy isoflavones extract on lipid profile in postmenopausal women, as compared with placebo or protein of milk, casein or isolated soy protein with or without trace isoflavone content. We used the following databases: MEDLINE (PubMed), EMBASE and the Cochrane Library. Quantitative data synthesis was performed by applying a random-effects model. Subgroup analysis and meta-regression were performed to assess the modifiers of treatment response. In total, in the analysis studies, 2305 postmenopausal women took part. Changes in the lipid profile showed statistically significant decreases of total cholesterol by −0.12 (95% CI: −0.21, −0.03) mmol/L, −4.64 (95% CI: −8.12, −1.16) mg/dL, p = 0.01 and increased HDL-cholesterol by 0.03 (95% CI: 0.00, 0.06) mmol/L, 1.15 (95% CI: 0.00, 1.93) mg/dL, p = 0.05, as well as in LDL-cholesterol −0.05 (95% CI: −0.11, 0.01) mmol/L, −1.93 (95% CI: −4.25, 0.39) mg/dL, p = 0.08 and triacylglycerols −0.07 (95% CI: −0.14, 0.00) mmol/L, −6.123 (95% CI: −12.25, 0.00) mg/dL, p = 0.06. Our results suggests that soy and its isoflavones can be effective in correction changes in lipid metabolism in postmenopausal women and may favorably influence in preventing cardiovascular events.

Effects of daidzein and genistein on markers of cardiovascular disease risk among women with impaired glucose regulation: a double-blind, randomized, placebo-controlled trial

BACKGROUND AND OBJECTIVE

soy protein and soy isoflavones have been suggested to be associated with improved cardiovascular risk factors (e.g., lipid profiles and uric acid (UA)), but few studies have been conducted among women with impaired glucose regulation (IGR). This study is aimed to evaluate the effect of isolated daidzein and genistein on lipid profiles, high sensitive C-reactive protein (hs-CRP), and uric acid (UA) among Chinese women with IGR.

METHODS AND RESULTS

this randomized, double-blind, and placebo-controlled trial was conducted in 165 Chinese women aged 30-70 years with IGR. Participants were randomly assigned to one of the three groups: 0 mg of daidzein and genistein with 10 g soy protein (placebo group), 50 mg of daidzein with 10 g soy protein (daidzein group), or 50 mg of genistein with 10 g soy protein (genistein group) supplementation for 24 weeks. Fasting serum total cholesterol (TC), triacylglycerol (TG), high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), lipoprotein a (LP (a)), hs-CRP, and UA were assessed at baseline, 12, and 24 weeks after intervention. The results showed no significant differences in the changes (%) of TC, TG, HDL-C, LDL-C, LP (a), hs-CRP, and UA between the three treatment groups at weeks 12 or 24 (all P > 0.05).

CONCLUSION

neither isolated daidzein nor genistein had a significant effect on cardiovascular health in Chinese women with IGR.

Beneficial effect of soy isoflavones and soy isoflavones plus soy protein on serum concentration of C-reactive protein among postmenopausal women: An updated systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Scientists suggest that soy isoflavones or the combination of soy isoflavones and soy protein may have beneficial effects on inflammation. Thus, the present study aims at conducting a systematic review and meta-analysis on randomized controlled trials (RCTs) in which the effect of soy isoflavones and the combination of soy isoflavones and soy protein on serum concentration of C-reactive protein (CRP) among postmenopausal women is assessed.

METHODS AND MATERIALS

A literature searching was done to identify a breadth of related references in PubMed, Scopus, ISI Web of Science, Cochrane Library, and Clinicaltrials.gov up to December 2020. The mean change from baseline in the CRP concentrations and its standard deviation (SD) for both intervention and comparison groups were used to calculate the effect size. The summary of the overall effects and heterogeneity was estimated by using the DerSimonian and Laird random effects model. The protocol was registered in PROSPERO (No. CRD42020166053).

RESULTS

This study considered 23 articles for systematic review and 19 articles for meta-analysis. The overall effect presented a non-significant effect of soy isoflavones on serum CRP concentrations (WMD = 0.08 mg/L, 95 % CI: -0.08, 0.24; p = 0.302) and the overall effect of the combination of soy isoflavones and soy protein indicated non-significant effect in serum levels of CRP (WMD= -0.02 mg/L 95 % CI: -0.12, 0.08; p = 0.715).

CONCLUSION

Published RCTs did not provide strong evidence regarding beneficial effect of soy isoflavones or the combination of soy isoflavones and soy protein on serum CRP concentration among postmenopausal women.

Genistein for glycolipid metabolism in postmenopausal women: a meta-analysis

OBJECTIVE

This study aimed to evaluate the effects of genistein on glycolipid metabolism in postmenopausal women.

METHODS

Electronic databases were searched and relevant reports were hand-screened. We included only randomized controlled trials of isolated genistein for glycolipid metabolism. The primary outcome for lipid metabolism included a changed value of low-density lipoprotein cholesterol (LDL-C), and for glucose metabolism was a changed value of homeostasis model assessment for insulin resistance (HOMA-IR). Secondary outcomes included a changed value of total cholesterol, triglyceride, high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), fasting blood insulin (INS), and body mass index (BMI).

RESULTS

Ten trials with 11 articles were included. The level of LDL-C was not decreased in the genistein group compared with the placebo group (standardized mean difference [SMD] = -0.58; 95% confidence interval [CI] - 1.19, 0.02; p = 0.06). No statistical significance was found in subgroup analyses. HOMA-IR was obviously improved in the genistein group with SMD of -0.51 (95% CI -0.88, -0.14; p = 0.006). In subgroup analyses, HOMA-IR was improved more in women with BMI <30 kg/m² and without metabolic disorders (p < 0.0001). For secondary outcomes, there were significant differences in total cholesterol, HDL-C, FBG, and INS, but not triglyceride or BMI.

CONCLUSIONS

Genistein was effective in ameliorating glycolipid metabolism by increasing HDL-C levels and decreasing total cholesterol levels and improving insulin sensitivity.

The effects of soy supplementation on inflammatory biomarkers: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Soy products contain several compounds with anti-inflammatory properties like genistein and daidzein which reported to act through different pathways. Present study conducted considering the inconsistent results and lack of any comprehensive review regarding randomized controlled trials which assess the effect of soy products on inflammatory markers.

METHODS

Following electronic databases were searched up to March 2020: PubMed, Scopus, ISI web of science, and Cochrane Library All randomized trials which assessed the effect of soy product supplementation on c-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were included for last analysis. Treatment effects were expressed as mean difference (MD) and the standard deviation (SD) of outcomes. To estimate the overall effect the random-effects model was employed.

RESULTS

Finally, 51 randomized trial were included for present study. Last analysis showed that soy product supplementation lead to significant reduction in CRP (MD -0.27 mg/L; 95% CI: -0.51, -0.02, p = 0.028) but it did not affect IL-6 (MD 0.0 pg/ml; 95% CI: -0.06, 0.06, p = 0.970) and TNF-α (MD = -0.04 pg/ml; 95% CI: -0.11, 0.03, p = 0.252). Subgroup analysis showed that soy supplementation had a significant impact on decreasing IL-6 and TNF-α levels when studies had a long-term intervention (≥12 weeks) and used low dose isoflavone (<100 mg/day).

CONCLUSION

In conclusion, present systematic review and meta-analysis found a significant reduction in CRP levels after soy supplementation whiles IL-6 and TNF-α did not affect.

Pleotropic Effects of Polyphenols in Cardiovascular System

Numerous epidemiological and clinical studies demonstrate the beneficial effects of naturally occurring, polyphenol supplementations, on cardiovascular system. The present review emphasizes on the risk factors associated with cardiovascular disorders (involving heart and blood vessels), and overview of preclinical and clinical trials on polyphenols for the treatment of cardiovascular diseases. The review collaborates PUBMED, Google Scholar and Research gate databases, which were explored using keywords and their combinations such as polyphenols, cardiovascular disease, flavonoids, atherosclerosis, cardiovascular risk factors and several others, to create an eclectic manuscript. The potency and efficacy of these polyphenols are mainly depending upon the amount of consumption and bioavailability. Recent data showed that polyphenols also exert beneficial actions on vascular system by blocking platelet aggregation and oxidation of low-density lipoprotein (LDL), ameliorating endothelial dysfunction, reducing blood pressure, improving antioxidant defenses and alleviating inflammatory responses. Several studies evidently support the cardioprotective actions mediated by polyphenols, however, some studies or long-term follow-up of human studies, did not demonstrate decisive outcomes because of variations in dose regimen and lack of appropriate controls. Therefore, more data is required to explore the therapeutic benefits of bioactive compounds as a preventive therapy for CVDs.

Effect of Chinese herbal medicine on serum lipids in postmenopausal women with mild dyslipidemia: a randomized, placebo-controlled clinical trial

OBJECTIVE

Previous studies have shown the association between menopause and dyslipidemia. This study was aimed to evaluate the effect of Chinese herbal medicine, tonifying kidney and descending turbidity (TKDT) granule, on serum lipid profiles in postmenopausal women with dyslipidemia.

METHODS

A double-blind randomized, placebo-controlled trial was conducted among 104 postmenopausal Chinese women with mild dyslipidemia. Participants were randomized into treatment group (n = 53) and control group (n = 51). The participants in the treatment group received TKDT granule once per day for 24 weeks, whereas the control group received placebo in the same manner. All participants were subjected to healthy lifestyle during the study. Serum lipid profiles, body weight, waist circumference, and safety indicators were measured both at baseline and 24 weeks after admission.

RESULTS

Compared with placebo, significant improvements in total cholesterol, low-density lipoprotein cholesterol, apolipoprotein-B (Apo-B), weight, and waist circumference in the TKDT group (P < 0.05) were observed after 24 weeks of treatment. Total cholesterol, low-density lipoprotein cholesterol, and Apo-B were decreased by 0.84 (0.77) mmol/L, 0.72 (0.77) mmol/L, and 0.12 (0.27) mmol/L, mean ± SD respectively. The weight, waist circumference, and body mass index were decreased by 4.07 (3.01) kg, 3.10 (2.95) cm, 1.60 (1.13), respectively. There were no significant differences in triglycerides, high-density lipoprotein cholesterol, and Apo-A between the two groups. Seven participants in the treatment group and six participants in the placebo group had mild or moderate adverse reactions.

CONCLUSION

TKDT granule improved the lipid profile and reduced the related metabolic abnormalities in postmenopausal women with mild dyslipidemia based on lifestyle changes.

The effects of isolated soy protein, isolated soy isoflavones and soy protein containing isoflavones on serum lipids in postmenopausal women: A systematic review and meta-analysis

Background: Many randomized controlled trials (RCTs) have assessed the effects of soy products on serum lipids. However, the responsible soy components and the magnitude of effects in healthy or hypercholesterolemic postmenopausal women are unclear. This review assessed the quality of these RCTs and estimated the effects of isolated soy protein, isolated soy isoflavones and soy protein containing isoflavones on total cholesterol (TC), LDL-C, HDL-C, triglycerides (TG), Apolipoprotein (Apo) A-1 and Apo B among postmenopausal women.Design: Forty-six eligible randomized controlled trials published up to 20 May 2019 were identified from the PubMed, Web of Science and Scopus databases. Weighted mean effect sizes were calculated for net changes in serum lipid concentrations by using random-effect models. Specific subgroup analyses were performed to identify the effect of covariates on serum lipid changes.Results: Soy consumption was associated with significant decrease in TG (mean differences (MD): -5.04 mg/dl; 95% CI: -9.95, -0.13; P = 0.044), TC (MD: -3.02 mg/dl; 95% CI: -5.56, -0.47; P = 0.02), LDL-C (MD: -3.27 mg/dl; 95% CI: -6.01, -0.53; P = 0.019) and HDL-C (MD: -2.28 mg/dl; 95% CI: -4.27, -0.29; P = 0.025). The reduction in LDL-C, TG and HDL were larger in subjects consuming isolated soy protein than isolated soy isoflavones. There was a significant decrease in serum TG and HDL levels with dosages of >25 grams per day soy protein rather than lower dosages of soy protein. The reductions in Apo A-1 were significantly larger in hypercholesterolemic subjects than in healthy subjects.Conclusions: Isolated soy protein significantly reduced serum TG, TC, LDL-C, HDL-C and Apo-B levels in postmenopausal women. Isolated soy isoflavones had a significant lowering effect on serum TC and Apo B levels. Soy protein containing isoflavones significantly reduced TG, TC, LDL-C and Apo B levels. Therefore, hyperlipidemia risk reduction with soy products is not uniform and strongly depends on the protein and isoflavone content of soy products, duration and dosage of consumption.

Cumulative Meta-Analysis of the Soy Effect Over Time

Background

Soy protein foods have attracted attention as useful plant protein foods with mild cholesterol‐lowering effects that are suitable for inclusion in therapeutic diets. But on the basis of the lack of consistency in significant cholesterol reduction by soy in 46 randomized controlled trials, the US Food and Drug Administration (FDA) is reassessing whether the 1999 heart health claim for soy protein should be revoked.

Methods and Results

We have, therefore, performed a cumulative meta‐analysis on the 46 soy trials identified by the FDA to determine if at any time, since the 1999 FDA final rule that established the soy heart health claim, the soy effect on serum cholesterol lost significance. The cumulative meta‐analysis for both total cholesterol and low‐density lipoprotein cholesterol demonstrated preservation of the small, but significant, reductions seen both before and during the subsequent 14 years since the health claim was originally approved. For low‐density lipoprotein cholesterol, the mean reduction in 1999 was −6.3 mg/dL (95% CI, −8.7 to −3.9 mg/dL; P=0.00001) and remained in the range of −4.2 to −6.7 mg/dL (P=0.0006 to P=0.0002, respectively) in the years after 1999. At no time point did the total cholesterol or low‐density lipoprotein cholesterol reductions lose significance or were the differences at individual time points in the cumulative meta‐analysis significantly different from those seen in 1999 when the health claim was approved.

Conclusions

A cumulative meta‐analysis of the data selected by the FDA indicates continued significance of total cholesterol and low‐density lipoprotein cholesterol reduction after soy consumption and supports the rationale behind the original soy FDA heart health claim.

See Editorial Petersen and Kris‐Etherton

A Meta-Analysis of 46 Studies Identified by the FDA Demonstrates that Soy Protein Decreases Circulating LDL and Total Cholesterol Concentrations in Adults

BACKGROUND

Certain plant foods (nuts and soy protein) and food components (viscous fibers and plant sterols) have been permitted by the FDA to carry a heart health claim based on their cholesterol-lowering ability. The FDA is currently considering revoking the heart health claim for soy protein due to a perceived lack of consistent LDL cholesterol reduction in randomized controlled trials.

OBJECTIVE

We performed a meta-analysis of the 46 controlled trials on which the FDA will base its decision to revoke the heart health claim for soy protein.

METHODS

We included the 46 trials on adult men and women, with baseline circulating LDL cholesterol concentrations ranging from 110 to 201 mg/dL, as identified by the FDA, that studied the effects of soy protein on LDL cholesterol and total cholesterol (TC) compared with non-soy protein. Two independent reviewers extracted relevant data. Data were pooled by the generic inverse variance method with a random effects model and expressed as mean differences with 95% CI. Heterogeneity was assessed and quantified.

RESULTS

Of the 46 trials identified by the FDA, 43 provided data for meta-analyses. Of these, 41 provided data for LDL cholesterol, and all 43 provided data for TC. Soy protein at a median dose of 25 g/d during a median follow-up of 6 wk decreased LDL cholesterol by 4.76 mg/dL (95% CI: -6.71, -2.80 mg/dL, P < 0.0001; I2 = 55%, P < 0.0001) and decreased TC by 6.41 mg/dL (95% CI: -9.30, -3.52 mg/dL, P < 0.0001; I2 = 74%, P < 0.0001) compared with non-soy protein controls. There was no dose-response effect or evidence of publication bias for either outcome. Inspection of the individual trial estimates indicated most trials (∼75%) showed a reduction in LDL cholesterol (range: -0.77 to -58.60 mg/dL), although only a minority of these were individually statistically significant.

CONCLUSIONS

Soy protein significantly reduced LDL cholesterol by approximately 3-4% in adults. Our data support the advice given to the general public internationally to increase plant protein intake. This trial was registered at clinicaltrials.gov as NCT03468127.

A systematic review and meta-analysis of the effects of soy on serum hs-CRP

BACKGROUND & AIM

The results of studies about the effect of soy products on serum highly sensitive C-reactive protein (hs-CRP) are inconsistent. The aim of this systematic review and meta-analysis of randomized clinical trials (RCTs) was to investigate the effect of soy products intake on serum hs-CRP concentration.

METHODS

We searched PubMed, EMBASE, Science Direct, ISI Web of Science, Google Scholar and Cochrane Central Register of Controlled Trials up to December 2016 without language restrictions. Random-effect model was used for quantitative data synthesis.

RESULTS

Thirty-six studies were included in our analyses. A meta-analysis revealed a non-significant reduction in serum hs-CRP concentrations following soy products consumption, -0.19 (mg/L) (95% CI: -0.49 to 0.09; I2 = 95.6%). Subgroup analyses suggested that natural soya products may reduce plasma levels of CRP by -0.18 mg/L (95% CI: -0.28 to -0.08; I2: 11.6) in comparison to other source of isoflavones (soya extracts, supplements). Moreover, the effect was stronger among subjects with baseline hs-CRP concentrations of less than 2.52 mg/L, -0.15 (95% CI: -0.27 to -0.02; I2: 34.6). A meta-regression analysis revealed that dosage of isoflavones seems to be a strong predictor of the effect of soya on serum hs-CRP levels.

CONCLUSION

Present review of RCTs published up to December 2016 did not provide strong evidence regarding the beneficial effect of soya products consumption on blood hs-CRP concentrations. However, it appears that natural soya products may reduce plasma levels of hs-CRP in comparison to other source of isoflavones. Large and well-designed studies are recommended to confirm this conclusion.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018069371.

Clinical and metabolic response to soy administration in older women with metabolic syndrome: a randomized controlled trial

BACKGROUND

There are many studies on the health effects of soy, only a few describe the effects of the simultaneous use of two types of soy on multiple components of metabolic syndrome (MetS). The present study was designed to determine the effects of roasted soy-nut and textured soy protein (TSP) intake on clinical and metabolic status of older women with MetS borderline parameters.

METHOD

This randomized, single-blind, controlled clinical trial included 75 women ≥ 60 years old with a diagnosis of MetS based on ATP III criteria. The participants were randomly allocated into three groups of 25 people; soy-nut, TSP and control groups for 12 week. Fasting blood samples were taken at the beginning and end of the trial to compare the metabolic responses. All participants provided three dietary records and physical activity records during the intervention. We used the Kolmogorov-Smirnov, ANOVA, ANCOVA, paired-t test, and the Generalized Linear Model (GLM) repeated measures analysis.

RESULTS

Dietary intake and physical activity of the participants in two groups were not significantly different. After 12 weeks of intervention the participants who received soy-nut had a significant decrease in total cholesterol (TC) (p < 0.001), low density lipoprotein, very low density lipoprotein, apolipoprotein B100, fasting blood glucose, insulin (p < 0.05), HOMA-IR, malondialdehyde (MDA) (p < 0.01) level. Morever, a significant increase in total antioxidant capacity (TAC) (p < 0.01) level compared with the control group. At the same time, the TSP brought significant decrease only in TC, insulin, MDA (p < 0.05) level and a significant increase in total TAC (p < 0.05) level. We did not find any significant effect in intervention groups, on apolipoprotein AI, triglyceride (TG), high density lipoprotein (HDL-C), TG/HDL, C-reactive protein and fibrinogen levels after intervention.

CONCLUSION

Short-term intakes of roasted soy-nut and TSP have shown to improve the lipid profiles, markers of glucose intolerance and oxidative stress; although the roasted soy-nut was more effective than TSP. Therefore, a moderate daily intake of roasted soy-nut as snacks or TSP as a meal complement by individuals with borderline parameters of MetS can be a safe and a practical modality to avoid the progression of the disease as well as to limit the side effects of drug intake.Trial registration MUBABOL.REC.1388.1.

Non-Hormonal Replacement Therapy Regimens: Do they have an Effect on Cardiovascular Risk?

INTRODUCTION

Menopause is associated with adverse effects on quality of life of perimenopausal and post-menopausal women. It also has an impact on the development of cardiovascular disease (CVD). Hormonal treatments are the most effective medications for menopausal symptoms relief. Given the fact that hormonal treatments are contraindicated for many women, non-hormonal treatment, such as Selective Serotonin Reuptake Inhibitors (SSRIs), Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs), gabapentin, pregabalin, clonidine and phytoestrogens, constitute alternative treatments. Nevertheless, little is known about their effects on CVD risk.

METHODS

PubMed, EMBASE and Cochrane Library were searched for the effects of non-hormonal treatment on CVD risk, blood pressure, heart rate, lipids and glucose concentrations, weight gain, cardiovascular events, stroke, mortality and morbidity.

RESULTS

Phytoestrogens, pregabalin and gabapentin seem to have no adverse effects on the cardiovascular system. Phytoestrogens, in particular, seem to reduce CVD risk through many pathways. On the other hand, SSRIs and SNRIs, although effective in reducing menopausal vasomotor symptoms, should be cautiously administered to women with known CVD (e.g. with cardiac arrhythmias, atherosclerotic disease or stroke). As clonidine has been associated with cardiovascular adverse effects, it should be administered only in cases where blood pressure regulation is mandatory.

CONCLUSION

Further research is needed to produce definite conclusions regarding the cardiovascular safety of non-hormonal medications for menopausal symptoms relief.

Effect of Plant Protein on Blood Lipids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

There is a heightened interest in plant-based diets for cardiovascular disease prevention. Although plant protein is thought to mediate such prevention through modifying blood lipids, the effect of plant protein in specific substitution for animal protein on blood lipids remains unclear. To assess the effect of this substitution on established lipid targets for cardiovascular risk reduction, we conducted a systematic review and meta-analysis of randomized controlled trials using the Grading of Recommendations Assessment, Development, and Evaluation system.

METHODS AND RESULTS

MEDLINE, EMBASE, and the Cochrane Registry were searched through September 9, 2017. We included randomized controlled trials of ≥3 weeks comparing the effect of plant protein in substitution for animal protein on low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and apolipoprotein B. Two independent reviewers extracted relevant data and assessed risk of bias. Data were pooled by the generic inverse variance method and expressed as mean differences with 95% confidence intervals. Heterogeneity was assessed (Cochran Q statistic) and quantified (I2 statistic). The overall quality (certainty) of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation system. One-hundred twelve randomized controlled trials met the eligibility criteria. Plant protein in substitution for animal protein decreased low-density lipoprotein cholesterol by 0.16 mmol/L (95% confidence interval, -0.20 to -0.12 mmol/L; P<0.00001; I2=55%; moderate-quality evidence), non-high-density lipoprotein cholesterol by 0.18 mmol/L (95% confidence interval, -0.22 to -0.14 mmol/L; P<0.00001; I2=52%; moderate-quality evidence), and apolipoprotein B by 0.05 g/L (95% confidence interval, -0.06 to -0.03 g/L; P<0.00001; I2=30%; moderate-quality evidence).

CONCLUSIONS

Substitution of plant protein for animal protein decreases the established lipid targets low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and apolipoprotein B. More high-quality randomized trials are needed to improve our estimates.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02037321.

Effects of Vegetables on Cardiovascular Diseases and Related Mechanisms

Epidemiological studies have shown that vegetable consumption is inversely related to the risk of cardiovascular diseases. Moreover, research has indicated that many vegetables like potatoes, soybeans, sesame, tomatoes, dioscorea, onions, celery, broccoli, lettuce and asparagus showed great potential in preventing and treating cardiovascular diseases, and vitamins, essential elements, dietary fibers, botanic proteins and phytochemicals were bioactive components. The cardioprotective effects of vegetables might involve antioxidation; anti-inflammation; anti-platelet; regulating blood pressure, blood glucose, and lipid profile; attenuating myocardial damage; and modulating relevant enzyme activities, gene expression, and signaling pathways as well as some other biomarkers associated to cardiovascular diseases. In addition, several vegetables and their bioactive components have been proven to protect against cardiovascular diseases in clinical trials. In this review, we analyze and summarize the effects of vegetables on cardiovascular diseases based on epidemiological studies, experimental research, and clinical trials, which are significant to the application of vegetables in prevention and treatment of cardiovascular diseases.

Multidimensional Effects of Soy Isoflavone by Food or Supplements in Menopause Women: A Systematic Review and Bibliometric Analysis

Isoflavones can exert their action on various levels: on cardiovascular system, bone and muscle health, on cancer, on menopausal symptoms, on obesity, on thyroid and on cognitive function. The aim of this systematic review is to evaluate the multidimensional effects of phytoestrogens in postmenopausal woman, and specifically to explore the impact on scientific literature. A research strategy was planned on PubMed and Scopus by defining the following key words:: menopause, climacteric, soy, isoflavone, phytoestrogens, cardiovascular system, bone mineral density, muscle mass, cancer, thyroid, obesity, cognitive. A total of 43 studies (in humans) were retrieved. The majority (12) describe the applications of soy isoflavones on cardiovascular disease, followed by effects on bone and muscle health (9), and studies concerning their action on menopausal symptoms (7), on cancer (6), on obesity (4), on cognitive function (3) and on thyroid function (2). The citation analysis revealed a growing interest for this topic and the papers on thyroid function are the most cited. Citation trends of the articles regarding the action on cardiovascular disease and on obesity are growing in the last years. Concerning the research areas, this review has assessed the effectiveness of various activities of isoflavones on welfare of menopausal women. In particular, literature show that a specific dosage of isoflavones reduces cardiovascular disease (from 20 to 100 mg/die), may be protective in osteoporosis and muscular fatigue (from 20 to 80 mg/die), may be useful for cancer prevention on endometrium, mammary glands and liver (from 50 to 100 mg/die), might improve menopausal symptoms, particularly in reducing the frequency of hot flashes (from 50 to 120 mg/die), can reduce abdominal fat and circulating inflammatory markers (from 80 to 160 mg/die), may ameliorate the possible interaction between endogenous estrogen and thyroid function (75 mg/die) and improve visual memory (from 50 to 100 mg/die).

Daidzein impairs Leydig cell testosterone production and Sertoli cell function in neonatal mouse testes: An in vitro study

Isoflavone is a type of phytoestrogen that exists in soy‑based products. Previous studies have reported that certain foods containing isoflavones, particularly infant formula, may have potential adverse effects on male reproductive function. However, few studies have focused on the effects of isoflavones on testosterone biosynthesis and Sertoli cell function during the neonatal period. The aim of the present study was to investigate the influence of daidzein, a common isoflavone, on testosterone secretion and Sertoli cell function during the neonatal period. The organ culture method was used to assess the effects of daidzein on neonatal mouse testes. Cultured testes were treated with daidzein (0, 0.03, 0.3, 3 or 30 µmol/l) for 72 h. To verify the mechanism of action of daidzein on androgen production, Leydig cells were also treated with daidzein for 24 h. As anticipated, testosterone secretions were suppressed by daidzein (30 µmol/l) in cultured testes and Leydig cells. Further analysis demonstrated that the expression levels of steroidogenic acute regulatory protein (StAR), cholesterol side‑chain cleavage enzyme (P450scc) and 3β‑hydroxysteroid dehydrogenase (3β‑HSD), which are transport proteins and key enzymes in androgen biosynthesis, were suppressed in cultured neonatal mouse testes. In addition, the expression levels of StAR, P450scc, 3β‑HSD and 17α‑hydroxylase/20‑lyase were decreased in Leydig cells. Notably, proliferation of Sertoli cells was also inhibited by daidzein (30 µmol/l). Furthermore, the expression levels of vimentin were significantly suppressed in the testes following treatment with daidzein, whereas inhibin B expression exhibited no change. In conclusion, daidzein may suppress steroidogenic capability and impair Sertoli cell function in the neonatal period in vitro.

Polyphenol-based nutraceuticals for the prevention and treatment of cardiovascular disease: Review of human evidence

BACKGROUND

In addition to prescription drugs, nutraceuticals/functional foods/medical foods are being increasingly added as adjunct treatment of cardiovascular disease (CVD), even though most of them have been exclusively studied in vitro.

HYPOTHESIS/PURPOSE

We review the available evidence (focusing on when the amount of polyphenols' intake was measured) coming from randomized controlled trials (RCTs) of (poly)phenol-based supplements.

CONCLUSION

We conclude that (poly)phenol-based nutraceuticals and functional foods might be indeed used as adjunct therapy of CVD, but additional long-term RCTs with adequate numerosity and with clinically relevant end points are needed to provide unequivocal evidence of their clinical usefulness.

Randomised controlled trial of effect of whole soy replacement diet on features of metabolic syndrome in postmenopausal women: study protocol

INTRODUCTION

Metabolic syndrome (MetS) is a public health problem in postmenopausal women. Whole soy foods are rich in unsaturated fats, high quality plant protein and various bioactive phytochemicals that may have a beneficial role in the management of MetS. The aim of the study is to examine the effect of whole soy replacement diet on the features of MetS among postmenopausal women.

METHODS AND ANALYSIS

This will be a 12-month, randomised, single-blind, parallel controlled trial among 208 postmenopausal women at risk of MetS or with early MetS. After 4 weeks' run-in, subjects will be randomly allocated to one of two intervention groups, whole soy replacement group or control group, each for 12 months. Subjects in the whole soy group will be required to include four servings of whole soy foods (containing 25 g soy protein) into their daily diet iso-calorically, replacing red or processed meat and high fat dairy products. Subjects in the control group will remain on a usual diet. The outcome measures will include metabolic parameters as well as a 10-year risk for ischaemic cardiovascular disease. We hypothesise that the whole soy substitution diet will notably improve features of MetS in postmenopausal women at risk of MetS or with early MetS. The study will have both theoretical and practical significance. If proven effective, the application of the whole soy replacement diet model will be a safe, practical and economical strategy for MetS prevention and treatment.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the Ethics Committee of the Chinese University of Hong Kong. The results will be disseminated via conference presentations and papers in academic peer reviewed journals. Data files will be deposited in an accessible repository.

TRIAL REGISTRATION NUMBER

NCT02610322.

Soy Protein Supplementation Reduces Clinical Indices in Type 2 Diabetes and Metabolic Syndrome

PURPOSE

Clinical trials have studied the use of soy protein for treating type 2 diabetes (T2D) and metabolic syndrome (MS). The purpose of this study was to outline evidence on the effects of soy protein supplementation on clinical indices in T2D and MS subjects by performing a meta-analysis of randomized controlled trials (RCTs).

MATERIALS AND METHODS

We searched PubMed, EMBASE, and Cochrane databases up to March 2015 for RCTs. Pooled estimates and 95% confidence intervals (CIs) were calculated by the fixed-and-random-effects model. A total of eleven studies with eleven clinical variables met the inclusion criteria.

RESULTS

The meta-analysis showed that fasting plasma glucose (FPG) [weighted mean difference (WMD), -0.207; 95% CI, -0.374 to -0.040; p=0.015], fasting serum insulin (FSI) (WMD, -0.292; 95% CI, -0.496 to -0.088; p=0.005), homeostasis model of assessment for insulin resistance index (HOMA-IR) (WMD, -0.346; 95% CI, -0.570 to -0.123; p=0.002), diastolic blood pressure (DBP) (WMD, -0.230; 95% CI, -0.441 to -0.019; p=0.033), low-density lipoprotein cholesterol (LDL-C) (WMD, -0.304; 95% CI, -0.461 to -0.148; p=0.000), total cholesterol (TC) (WMD, -0.386; 95% CI, -0.548 to -0.225; p=0.000), and C-reactive protein (CRP) (WMD, -0.510; 95% CI, -0.722 to -0.299; p=0.000) are significant reduced with soy protein supplementation, compared with a placebo control group, in T2D and MS patients. Furthermore, soy protein supplementation for longer duration (≥6 mo) significantly reduced FPG, LDL-C, and CRP, while that for a shorter duration (<6 mo) significantly reduced FSI and HOMA-IR.

CONCLUSION

Soy protein supplementation could be beneficial for FPG, FSI, HOMA-IR, DBP, LDL-C, TC, and CRP control in plasma.

Greater flavonoid intake is associated with improved CVD risk factors in US adults

Epidemiological studies have reported that diets high in flavonoids are associated with a reduced risk of CVD. However, evidence on the association of dietary flavonoid intake with CVD risk factors is still scarce. The present study aimed to investigate the association of dietary flavonoid intake with CVD risk factors among US adults in the National Health and Nutrition Examination Survey (NHANES) 2007-2012. A total of 4042 US adults aged 19 years and older from the NHANES 2007-2012 participated in this cross-sectional, population-based study. Intakes of total and individual flavonoids were estimated from 2-d 24-h diet recall data by matching with the expanded US Department of Agriculture flavonoid, isoflavone and proanthocyanidin databases. After adjusting for covariates, increased HDL-cholesterol was associated with higher total flavonoid intake (0·54 % change). TAG and TAG:HDL-cholesterol ratio were inversely associated with anthocyanidin (-1·25 % change for TAG; -1·60 % change for TAG:HDL-cholesterol ratio) and total flavonoid intakes (-1·31 % change for TAG; -1·83 % change for TAG:HDL-cholesterol ratio), respectively. Insulin and homoeostasis model assessment for insulin resistance (HOMA-IR) were inversely associated with flavone (for insulin, -3·18 % change; 95 % CI -5·85, -0·44; for HOMA-IR, -3·10 % change; 95 % CI -5·93, -0·19) and isoflavone intakes (for insulin, -3·11 % change; 95 % CI -5·46, -0·70; for HOMA-IR, -4·01 % change; 95 % CI -6·67, -1·27). BMI was negatively associated with anthocyanidin intake (-0·60 % change). This study showed that higher flavonoid intake was associated with improved CVD risk factors. Further research is warranted to confirm the findings from this study as these associations were moderate in strength.

Effects of Soy Flour Fortified Bread Consumption on Cardiovascular Risk Factors According to APOE Genotypes in Overweight and Obese Adult Women: A Cross-over Randomized Controlled Clinical Trial

Recent studies suggest that inclusion of soy product in the diet may have favorable effects on relief of cardiovascular diseases (CVDs) and risk factors. These effects might be associated with the presence of specific polymorphism in gene. The aim of this study was to examine the effects of consumption of soy flour fortified bread on cardiovascular risk factors in overweight and obese women according to APOE genotype. In a randomized cross-over clinical trial 30 overweight and obese women received a mild weight loss diet and assigned to a regular diet and a soy bread diet, each for 6 weeks and a washout period for 20 days. Subjects in the soy bread diet were asked to replace 120 grams of their daily usual bread intake with equal amount of soy bread. No significant effects of soy bread on serum lipid, systolic blood pressure and anthropometric indices were observed compared to the regular diet (p > 0.05). For diastolic blood pressure (DBP), comparison of mean differences between two groups showed a marginally significant effect of soy bread (p = 0.06). Compared to regular diet, soy bread had a significant effect on DBP in E2 genotype group (ε2/ε2) (p = 0.03). Having ε2 allele may influences responses of CVD risk factor to soy bread consumption. However more nutrigenetic studies are required.

A Systematic Review of the Efficacy of Bioactive Compounds in Cardiovascular Disease: Phenolic Compounds

The prevalence of cardiovascular diseases (CVD) is rising and is the prime cause of death in all developed countries. Bioactive compounds (BAC) can have a role in CVD prevention and treatment. The aim of this work was to examine the scientific evidence supporting phenolic BAC efficacy in CVD prevention and treatment by a systematic review. Databases utilized were Medline, LILACS and EMBASE, and all randomized controlled trials (RCTs) with prospective, parallel or crossover designs in humans in which the effects of BAC were compared with that of placebo/control were included. Vascular homeostasis, blood pressure, endothelial function, oxidative stress and inflammatory biomarkers were considered as primary outcomes. Cohort, ecological or case-control studies were not included. We selected 72 articles and verified their quality based on the Scottish Intercollegiate Guidelines Network, establishing diverse quality levels of scientific evidence according to two features: the design and bias risk of a study. Moreover, a grade of recommendation was included, depending on evidence strength of antecedents. Evidence shows that certain polyphenols, such as flavonols can be helpful in decreasing CVD risk factors. However, further rigorous evidence is necessary to support the BAC effect on CVD prevention and treatment.

Antioxidants: Characterization, natural sources, extraction and analysis

Recently many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However none of them has all the information regarding antioxidants (chemistry, sources, extraction and quantification). This article tries to take a different perspective on antioxidants for the new researcher involved in this field. Antioxidants from fruit, vegetables and beverages play an important role in human health, for example preventing cancer and cardiovascular diseases, and lowering the incidence of different diseases. In this paper the main classes of antioxidants are presented: vitamins, carotenoids and polyphenols. Recently, many analytical methodologies involving diverse instrumental techniques have been developed for the extraction, separation, identification and quantification of these compounds. Antioxidants have been quantified by different researchers using one or more of these methods: in vivo, in vitro, electrochemical, chemiluminescent, electron spin resonance, chromatography, capillary electrophoresis, nuclear magnetic resonance, near infrared spectroscopy and mass spectrometry methods.

Bioavailability, bioactivity and impact on health of dietary flavonoids and related compounds: an update

There is substantial interest in the role of plant secondary metabolites as protective dietary agents. In particular, the involvement of flavonoids and related compounds has become a major topic in human nutrition research. Evidence from epidemiological and human intervention studies is emerging regarding the protective effects of various (poly)phenol-rich foods against several chronic diseases, including neurodegeneration, cancer and cardiovascular diseases. In recent years, the use of HPLC-MS for the analysis of flavonoids and related compounds in foods and biological samples has significantly enhanced our understanding of (poly)phenol bioavailability. These advancements have also led to improvements in the available food composition and metabolomic databases, and consequently in the development of biomarkers of (poly)phenol intake to use in epidemiological studies. Efforts to create adequate standardised materials and well-matched controls to use in randomised controlled trials have also improved the quality of the available data. In vitro investigations using physiologically achievable concentrations of (poly)phenol metabolites and catabolites with appropriate model test systems have provided new and interesting insights on potential mechanisms of actions. This article will summarise recent findings on the bioavailability and biological activity of (poly)phenols, focusing on the epidemiological and clinical evidence of beneficial effects of flavonoids and related compounds on urinary tract infections, cognitive function and age-related cognitive decline, cancer and cardiovascular disease.

Daidzein supplementation decreases serum triglyceride and uric acid concentrations in hypercholesterolemic adults with the effect on triglycerides being greater in those with the GA compared with the GG genotype of ESR-β RsaI

Daidzein (one of the major isoflavones) can be metabolized to equol in certain individuals. The effects of isoflavones alone and equol status on lipid profiles are still controversial. To evaluate the 6-mo effects of daidzein on cardiovascular risk factors in hypercholesterolemic individuals and the interactions of these effects with equol status and estrogen receptor (ESR) genotypes, we conducted a randomized, double-blind, placebo-controlled trial consisting of 210 hypercholesterolemic adults (40-65 y old). The participants were randomly assigned (177 completed) to consume placebo, 40 mg daidzein (DAI40), or 80 mg daidzein (DAI80) daily for 6 mo. Daidzein decreased serum triglycerides (TGs) by 0.15 ± 0.62 mmol/L (mean ± SD) and 0.24 ± 0.61 mmol/L and decreased serum uric acid by 23 ± 47 μmol/L and 29 ± 44 μmol/L in the DAI40 and DAI80 groups, respectively. These reductions in the DAI40 and DAI80 groups were greater than those in the placebo group (P < 0.05). Other blood lipids, glucose, insulin, or glycated hemoglobin did not significantly change after daidzein treatment. No dose-dependent effects of daidzein were found. The reduction of TGs was influenced by the ESR genotype, with a greater effect observed in participants with the GA genotype compared with those with the GG genotype of ESR-β RsaI. These effects were not influenced by equol status. Six-month supplementation of daidzein significantly decreased TGs and uric acid. ESR-β RsaI genotype, not equol status, influenced daidzein's effects on TGs. Daidzein consumption may be effective to improve cardiovascular risk factors, especially in adults with the GA genotype of ESR-β RsaI. This trial was registered at the Chinese clinical trial registry as ChiCTR-TRC-10001048.

The inhibitory effect of black soybean on hepatic cholesterol accumulation in high cholesterol and high fat diet-induced non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is defined as excess of fat in the liver. We investigated the effects of black soybean on the cholesterol metabolism and insulin resistance of mice fed high cholesterol/fat diets. Mice were randomly allocated into four groups that were fed different diets: the normal cholesterol/fat diet; high cholesterol/fat diets (HCD); and HCD with 1%, and 4% black soybean powder (1B-HCD, and 4B-HCD). Liver total cholesterol and triglyceride concentrations were significantly lower in the black soybean-supplemented groups than that in the HCD group. PCR revealed significantly lower hepatic SREBP2 and HMG-CoA reductase mRNA levels of black soybean-supplemented mice. Real-time PCR revealed significantly higher hepatic ABCA1 mRNA level of black soybean-supplemented mice, which may increase cholesterol efflux. Liver bile acids concentration was significantly high in the 4B-HCD group. Black soybean stimulated secretion of adiponectin, activation of pAMPK, and eliminated free fatty acids in the liver. Black soybean supplementation decreased MDA and nitrate level. The activities of SOD, catalase, and GPx were restored by black soybean supplementation. Our data strongly indicate that black soybean influences the balance between oxidative and antioxidative stress. We suggest that black soybean improves cholesterol metabolism, insulin resistance, and alleviates oxidative damage in NAFLD.

Independent beneficial effects of aged garlic extract intake with regular exercise on cardiovascular risk in postmenopausal women

The purpose of the study was to assess the effects of a 12 weeks aged garlic extract (AGE) regimen with regular exercise on cardiovascular disease (CVD) risk in postmenopausal women. A total of 30 postmenopausal women (54.4 ± 5.4 years) were randomly divided into the following four groups: Placebo (Placebo; n = 6), AGE intake (AGEI; n = 8), exercise and placebo (Ex + Placebo; n = 8), exercise and AGE (Ex + AGE; n = 8) groups. The AGE group consume 80 mg per day, and exercise groups performed moderate exercise (aerobic and resistance) three times per week. After 12 weeks of treatment, body composition, lipid profile, and CVD risk factors were analyzed. Body weight was significantly decreased in AGEI, Ex + Placebo, and Ex + AGE groups compared to baseline. Body fat % was significantly decreased in the AGEI and Ex + Placebo groups. Body mass index (BMI) was significantly decreased in the AGEI, Ex + Placebo, and Ex + AGE groups. Fat-free mass was significantly decreased in the AGEI group. Total cholesterol (TC) was significantly lower in the Ex + Placebo compared to the Placebo group. AGE supplementation or exercise effectively reduced low-density lipoprotein (LDL-C). Triglyceride (TG) was significantly increased in the AGEI group. Malondialdehyde (MDA) levels were significantly decreased in the AGEI, Ex + Placebo, and Ex + AGE compared to the placebo group. AGE supplementation reduced homocysteine levels regardless of whether the women also exercised. The present results suggest that AGE supplementation reduces cardiovascular risk factors independently of exercise in postmenopausal women.

Combined effects of exercise and soy isoflavone diet on paraoxonase, nitric oxide and aortic apoptosis in ovariectomized rats

Menopause is associated with an increased risk of cardiovascular disease (CVD). Exercise and soy isoflavone diets have been suggested to reduce the risk of CVD in postmenopausal women. We investigated the effects of exercise, or combined exercise and soy isoflavone diet, on plasma lipid profiles, paraoxonase (PON), nitric oxide (NO) and apoptosis in the aorta of ovariectomized (OVX) rats. Thirty-two female Sprague-Dawley rats were divided into four groups: OVX with general diet (OVX-GD), OVX with isoflavone diet (OVX-ISO), OVX-GD with exercise training (OVX-ET) and OVX-ISO with exercise training (OVX-ISO+ET). The experimental rats undertook treadmill training (30 min/day, 4 days/week) and/or were supplied a soy isoflavone diet (added to the experimental diet at 2.39 mg/g protein) for 12 weeks. Body weight and levels of total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C) increased in the OVX rats and HDL-C decreased. These effects were reduced by exercise and/or soy isoflavone supplementation. PON and NO activities were higher in the OVX-ISO+ET group than in the OVX-GD group. In addition, this group had lower caspase-9 and -3 and higher Bcl-2 expression, and there was less aortic apoptotic cell death. These results suggest that a combination of exercise and a soy isoflavone diet has beneficial effects in terms of protecting against cardiovascular risk factors by controlling lipid profiles and the related enzyme, PON, as well as NO activity and apoptosis of the aorta in OVX rats.