Soy milk powder supplemented with phytosterol esters reduced serum cholesterol level in hypercholesterolemia independently of lipoprotein E genotype: a random clinical placebo-controlled trial

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.

Apolipoprotein E Genetic Variant and Blood Lipid Responses to Plant Sterols: A Systematic Review and Pooled Analysis of Clinical Trials

Plant sterols/stanols are effective cholesterol-lowering agents. However, it is unclear whether the apolipoprotein E (ApoE) genetic variants influence it. We investigated whether ApoE genetic variants modulate the responses of blood lipids to dietary intervention plant sterols/stanols in adults and if the intervention dose and duration, as well as the age and status of participants, influence this effect. Randomized clinical trials were identified by searching databases in the Cochrane Library. Random-effect models were used to estimate the pooled effect size of each outcome of interest total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein cholesterol, and triglycerides. Meta-regression and subgroup analysis were used to investigate the effects of potential modifiers on the outcomes of interest. Eleven articles were selected from 3,248 retrieved abstracts. Plant sterol/stanol intervention was associated with a more significant reduction in LDL levels in the E3 group [-0.251 mmol/L; 95% confidence interval (95% CI), -0.488 to -0.015] compared with both the E4 and E2 groups. In E4 carriers, the plant sterol/stanol intervention dose and duration resulted in a larger decrease in LDL levels (-0.088027 mmol/L; 95% CI, -0.154690 to -0.021364). In conclusion, ApoE genetic variants affected the response of blood LDL levels to supplementation with plant sterols/stanols, as individuals with E3 variant showed significantly decreased LDL levels compared with the other genotypes. However, future studies recruiting participants according to their ApoE genetic variants are needed to confirm our conclusion.

Fermented camel milk influenced by soy extract: Apparent viscosity, viscoelastic properties, thixotropic behavior, and biological activities

During fermentation, camel milk forms a fragile, acid-induced gel, which is less stable compared with the gel formed by bovine milk. In this study, camel milk was supplemented with different levels of soy extract, and the obtained blends were fermented with 2 different starter culture strains (a high acidic culture and a low acidic culture). The camel milk-soy extract yogurt treatments were evaluated for pH value, acidity, total phenolic compounds, antioxidant capacities, degree of hydrolysis, α-amylase and α-glucosidase inhibition, angiotensin-converting enzyme inhibition, antiproliferative activities, and rheological properties after 1 and 21 d of storage at 4°C. The results revealed that some of the investigated parameters were significantly affected by the starter culture strain and storage period. For instance, the effect of starter cultures was evident for the degree of hydrolysis, antioxidant capacities, proliferation inhibition, and rheological properties because these treatments led to different responses. Furthermore, the characteristics of camel milk-soy extract yogurt were also influenced by the supplementation level of soy extract, particularly after 21 d of storage. This study could provide valuable knowledge to the dairy industry because it highlighted the characteristics of camel milk-soy yogurt prepared with 2 different starter culture strains.

Use of phytosterol-fortified foods to improve LDL cholesterol levels: A systematic review and meta-analysis

AIMS

The main objective was to assess if foods fortified with phytosterols (PS), including plant sterols and plant stanols, reduce low-density lipoprotein cholesterol (LDL-C) concentrations. The secondary objective was to determine the impact of different factors related to PS administration.

DATA SYNTHESIS

The search was carried out in MEDLINE, EMBASE, Web of Science, Scopus and The Cochrane Central Register of Controlled Trials (CENTRAL) databases up to March 2023. The meta-analysis was registered in the PROSPERO database (CRD42021236952). From a total of 223 studies, 125 were included. On average, PS lowered LDL-C 0.55 mmol/L [95% confidence interval (CI) = 10.82-12.67], and this decrease was significantly maintained for all analysed subgroups. A greater reduction in LDL-C levels was detected in relation to a higher daily PS dosage. The food format "Bread, biscuits, cereals", conditioned a lower decrease of 0.14 mmol/L (95%CI -8.71 to -2.16) in LDL-C levels, compared to the predominant food format group of "butter, margarine, spreads". No significant differences were detected with the other subgroups (treatment duration, intake pattern, number of daily intakes and concomitant statin treatment).

CONCLUSION

The present meta-analysis supported that the use of PS-fortified foods had a beneficial effect on LDL-C lowering. In addition, it was observed that the factors that influence a decline LDL-C levels were PS dose as well as the food format in which they were consumed.

Soy Consumption and the Risk of Type 2 Diabetes and Cardiovascular Diseases: A Systematic Review and Meta-Analysis

Soy is rich in plant protein, isoflavones, and polyunsaturated fatty acids. To clarify the associations between soy intake and type 2 diabetes (T2D) and cardiovascular diseases (CVDs) events, we performed a meta-analysis and review. A total of 1963 studies met the inclusion criteria, and 29 articles with 16,521 T2D and 54,213 CVDs events were identified by the eligibility criteria. During a follow-up of 2.5–24 years, the risk of T2D, CVDs, coronary heart disease, and stroke in participants with the highest soy consumption decreased by 17% (total relative risk (TRR) = 0.83, 95% CI: 0.74–0.93), 13% (TRR = 0.87, 95% CI: 0.81–0.94), 21% (TRR = 0.79, 95% CI: 0.71–0.88), and 12% (TRR = 0.88, 95% CI: 0.79–0.99), respectively, compared to the lowest sot consumption. A daily intake of 26.7 g of tofu reduced CVDs risk by 18% (TRR = 0.82, 95% CI: 0.74–0.92) and 11.1 g of natto lowered the risk of CVDs by 17% (TRR = 0.83, 95% CI: 0.78–0.89), especially stroke. This meta-analysis demonstrated that soy consumption was negatively associated with the risks of T2D and CVDs and a specific quantity of soy products was the most beneficial for the prevention of T2D and CVDs. This study has been registered on PROSPERO (registration number: CRD42022360504).

Effects of phytosterol supplementation on lipid profiles in patients with hypercholesterolemia: a systematic review and meta-analysis of randomized controlled trials

Phytosterols (PSs) have been reported to improve blood lipids in patients with hypercholesterolemia for many years. However, meta-analyses of the effects of phytosterols on lipid profiles are limited and incomplete. A systematic search of randomized controlled trials (RCTs) published in PubMed, Embase, Cochrane Library, and Web of Science from inception to March 2022 was conducted according to the 2020 preferred reporting items of the guidelines for systematic reviews and meta-analysis (PRISMA) statement. These included studies of people with hypercholesterolemia, comparing foods or preparations containing PSs with controls. Mean differences with 95% confidence intervals were used to estimate continuous outcomes for individual studies. The results showed that in patients with hypercholesterolemia, taking a diet containing a certain dose of plant sterol significantly reduced total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) (TC: Weight Mean Difference (WMD) [95% CI] = -0.37 [-0.41, -0.34], p < 0.001; LDL-C: WMD [95% CI] = -0.34 [-0.37, -0.30], p < 0.001). In contrast, PSs had no effect on high density lipoprotein cholesterol (HDL-C) or triglycerides (TGs) (HDL-C: WMD [95% CI] = 0.00 [-0.01, 0.02], p = 0.742; TG: WMD [95% CI] = -0.01 [-0.04, 0.01], p = 0.233). Also, a significant effect of supplemental dose on LDL-C levels was observed in a nonlinear dose-response analysis (p-nonlinearity = 0.024). Our findings suggest that dietary phytosterols can help reduce TC and LDL-C concentrations in hypercholesterolemia patients without affecting HDL-C and TG concentrations. And the effect may be affected by the food substrate, dose, esterification, intervention cycle and region. The dose of phytosterol is an important factor affecting the level of LDL-C.

Efficacy of Plant Sterol-Enriched Food for Primary Prevention and Treatment of Hypercholesterolemia: A Systematic Literature Review

Plant sterols/phytosterols (PSs) are molecules with a similar structure to cholesterol that have a recognized effect on elevated LDL concentrations (LDL-c). PSs are used as a natural therapy against elevated LDL-c in combination with a healthy diet and exercise. A systematic review was performed to evaluate the efficacy of PS-enriched foods in the treatment of hypercholesterolemia. Randomized controlled clinical studies reporting the use of PS-enriched foods to reduce LDL-c among adult individuals were retrieved and assessed for risk of bias. Meta-analyses were performed to assess changes in LDL-c by treatment, food matrix, LDL-c range, sterols dosage and risk of bias (RoB). In the 13 studies analyzed, LDL-c in PS-treated participants decreased by an average of 12.14 (8.98; 15.29) mg/dL. PS administration was statistically more effective in patients with LDL-c ≥ 140 mg/dL and for PS dosages > 2 g/day. It can be concluded that PSs can be used as an important primary prevention measure for hypercholesterolemia and as tertiary prevention for cardiovascular events in patients who already have mild to moderate LDL-c. However, in severe hypercholesterolemia and in cases of familial hypercholesterolemia, it is necessary to combine dietary treatment with the use of statins.

The Effect of Dietary Interventions on Hypertriglyceridemia: From Public Health to Molecular Nutrition Evidence

Approximately 25–50% of the population worldwide exhibits serum triglycerides (TG) (≥150 mg/dL) which are associated with an increased level of highly atherogenic remnant-like particles, non-alcoholic fatty liver disease, and pancreatitis risk. High serum TG levels could be related to cardiovascular disease, which is the most prevalent cause of mortality in Western countries. The etiology of hypertriglyceridemia (HTG) is multifactorial and can be classified as primary and secondary causes. Among the primary causes are genetic disorders. On the other hand, secondary causes of HTG comprise lifestyle factors, medical conditions, and drugs. Among lifestyle changes, adequate diets and nutrition are the initial steps to treat and prevent serum lipid alterations. Dietary intervention for HTG is recommended in order to modify the amount of macronutrients. Macronutrient distribution changes such as fat or protein, low-carbohydrate diets, and caloric restriction seem to be effective strategies in reducing TG levels. Particularly, the Mediterranean diet is the dietary pattern with the most consistent evidence for efficacy in HTG while the use of omega-3 supplements consumption is the dietary component with the highest number of randomized clinical trials (RCT) carried out with effective results on reducing TG. The aim of this review was to provide a better comprehension between human nutrition and lipid metabolism.

Fermented Soy Beverage Q-CAN Plus Consumption Improves Serum Cholesterol and Cytokines

Soy-based beverages are well recognized for their rich nutritional contents and positive health benefits. However, there is little information regarding the composition of various commercially available soy-based beverages and uncertainty among patients regarding the utility of fermented soy products. Current study evaluates the health benefits of QCAN® Plus-an easily available fermented soy drink. This study was performed in lean (n = 10) and obese (n = 10) subjects. The subjects were observed during pre-soy (weeks -2, -1, and 0), on-soy (weeks 1, 2, 3, and 4), and post-soy (weeks 6, 8, 10, and 12) periods. The serum samples during these visits were subjected to lipid profile analysis and multiplex assay for cytokines. The results revealed that total cholesterol and low-density lipoprotein (LDL) cholesterol levels were significantly reduced in both lean and obese individuals during on-soy (P ≤ .05). Furthermore, cytokines such as platelet-derived growth factor (PDGF) AA and AB/BB were significantly lowered on-soy compared with pre-soy (P ≤ .05) in lean subjects and PDGF AA, IL-1RA, and GMCSF were significantly reduced on-soy (P ≤ .05) in obese subjects. In addition, a qualitative and quantitative analysis of the Q-CAN Plus by a third-party laboratory confirmed its chemical and microbial safety. Our preliminary study on Q-CAN Plus ensures its safety for consumption and highlights its hypolipidemic and suppressive effect on certain cytokines. These observations and relevant studies in future might guide clinicians in future to consider Q-CAN Plus as a therapeutic nutritional supplement.

Antioxidant activity of Pistacia atlantica var mutica kernel oil and it's unsaponifiable matters

In this research, antioxidant activity of Pistacia atlantica var mutica (a wild type of pistachio in Iran) kernel oil (PAKO) and unsaponifiable matters of kernel oil (UKO) were compared with those of sesame seed oil (SSO) and rice bran oil (RBO) as well as with their unsaponifiable matters (USO and UBO) and α-tocopherol (natural antioxidant) was selected as control. Also, some chemical properties such as (FRAP, DPPH radical-scavenging, rancimat and oven assays (peroxide value and carbonyl value) were assessed. The amount of unsaponifiable matters of studied oils was between 1.4 and 3.5%. The highest total phenolics was observed in SSO (1024 mg/kg), followed by RBO, and PAKO was 174, and 75 mg/kg, respectively. In DPPH radical-scavenging assay, the EC₅₀ values of PAKO, SSO, RBO, UKO, USO, UBO, and α-tocopherol were determined as 38.9, 50, 48.4, 14, 12.7, 15.9 and 61.4 mg/mL, respectively. In FRAP assay, the highest value was nominated for UKO (434 mmol/L); followed by USO, UBO, PAKO, SSO, RBO and α-tocopherol (404, 357, 364, 298, 210 and 58 mmol/L; respectively). Also, considering the results of oven test, the incorporation of UKO into pure sunflower oil resulted in the highest oxidative stability; followed by UBO, USO, PAKO, SSO, RBO and α-tocopherol. According to results of the rancimat test, the incorporation of unsaponifiable matters (UKO, USO, and UBO) resulted in the highest oil/oxidative stability index (OSI) in pure sunflower oil, followed by oils studied (PAKO, SSO, and RBO). According to results, UKO had the highest antioxidant activity, followed by USO, UBO, PAKO, SSO, RBO, and α-tocopherol.

Dietary non-nutrients in the prevention of non-communicable diseases: Potentially related mechanisms

Among the 10 leading causes of death in developed countries are chronic non-communicable diseases (NCDs). The effect of these multifactorial diseases on public health has stimulated considerable research aimed at investigating their primary risk factors (genetic factors, stress, food intake, and amount of physical exercise). Thus, healthful foods (e.g., fruits, vegetables, oils, grains, and seeds) are sources of bioactive compounds that promote good health and disease prevention. Among their components are non-caloric substances identified as non-nutrients (polyphenols, phytosterols, saponins, and phytates), which have been found to have a role in modulating metabolic pathways, maintaining health, and preventing NCDs. The aim of this study is to demonstrate and review the performance of some non-nutrients, such as their antioxidant and anti-inflammatory action, modulation of the antiatherogenic lipid profile (higher high-density lipoprotein cholesterol, lower oxidized low-density lipoprotein, and triacylglycerols), reduction of glucose and fat intestinal absorption, increase in insulin sensitivity, and stimulation of nitic oxide synthesis.

Beyond the Cholesterol-Lowering Effect of Soy Protein: A Review of the Effects of Dietary Soy and Its Constituents on Risk Factors for Cardiovascular Disease

The hypocholesterolemic effect of soy is well-documented and this has led to the regulatory approval of a health claim relating soy protein to a reduced risk of cardiovascular disease (CVD). However, soybeans contain additional components, such as isoflavones, lecithins, saponins and fiber that may improve cardiovascular health through independent mechanisms. This review summarizes the evidence on the cardiovascular benefits of non-protein soy components in relation to known CVD risk factors such as hypertension, hyperglycemia, inflammation, and obesity beyond cholesterol lowering. Overall, the available evidence suggests non-protein soy constituents improve markers of cardiovascular health; however, additional carefully designed studies are required to independently elucidate these effects. Further, work is also needed to clarify the role of isoflavone-metabolizing phenotype and gut microbiota composition on biological effect.

Soy milk versus simvastatin for preventing atherosclerosis and left ventricle remodeling in LDL receptor knockout mice

Functional food intake has been highlighted as a strategy for the prevention of cardiovascular diseases by reducing risk factors. In this study, we compared the effects of oral treatment with soy milk and simvastatin on dyslipidemia, left ventricle remodeling and atherosclerotic lesion of LDL receptor knockout mice (LDLr-/-) fed a hyperlipidic diet. Forty 3-month old male LDLr-/- mice were distributed into four groups: control group (C), in which animals received standard diet; HL group, in which animals were fed a hyperlipidic diet; HL+SM or HL+S groups, in which animals were submitted to a hyperlipidic diet plus soy milk or simvastatin, respectively. After 60 days, both soy milk and simvastatin treatment prevented dyslipidemia, atherosclerotic lesion progression and left ventricle hypertrophy in LDLr-/- mice. These beneficial effects of soy milk and simvastatin were associated with reduced oxidative stress and inflammatory state in the heart and aorta caused by the hyperlipidic diet. Treatment with soy milk was more effective in preventing HDLc reduction and triacylglycerol and VLDLc increase. On the other hand, simvastatin was more effective in preventing an increase in total cholesterol, LDLc and superoxide production in aorta, as well as CD40L both in aorta and left ventricle of LDLr-/-. In conclusion, our results suggest a cardioprotective effect of soy milk in LDLr-/- mice comparable to the well-known effects of simvastatin.