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Mycotoxin-Linked Mutations and Cancer Risk: A Global Health Issue.
Ekwomadu, T, Mwanza, M, Musekiwa, A
International journal of environmental research and public health. 2022;19(13)
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Mycotoxins are toxic substances produced by fungi, which can be found in common foods like maize, wheat, nuts, and foods containing them. Mycotoxins such as aflatoxins, ochratoxin, fumonisins, zearalenone, and some Penicillium toxins can alter genetic material. According to previous studies, they can damage genetic material and affect cell growth. Usage of chemicals such as fertilizers and fungicides is a common practice in the agricultural industry to protect plants from fungus and to feed them. However, fungicides can accelerate mycotoxin production. 16 studies were included in this Systematic Review and 11 in Meta-Analysis. This research looked at the harmful effects of mycotoxins such as aflatoxins, fumonisins, ochratoxin, T2, zearalenone, and some Penicillium toxins in causing cancers. The researchers evaluated the link between aflatoxin exposure and liver cancer, fumonisin B1 exposure and liver cancer, zearalenone exposure and breast cancer, zearalenone exposure and cervical cancer, citrinine and patulin exposure and colorectal cancer, and NEO, HT-2, and T-2 exposure and Oesophageal cancer. This research did not show significant associations between various mycotoxins and cancer risk. As currently, most studies are primarily focused on aflatoxin; more robust studies are needed to assess the cancer risk associated with different mycotoxin exposure. Using the results of this study, healthcare professionals can gain a better understanding of how mycotoxins affect our bodies.
Abstract
Humans continue to be constantly exposed to mycotoxins, mainly through oral exposure (dietary), inhalation, or dermal contact. Recently, it has been of increasing interest to investigate mycotoxin-linked carcinogenicity. This systematic review was conducted to synthesize evidence of the association between mycotoxin-linked mutations and the risk of cancer, to provide an overview of the data linking exposure to different mycotoxins with human cancer risk, and to provide an update on current research on the risk of cancer associated with human exposure to mycotoxins. PRISMA guidelines were used when conducting the systematic review. PubMed, MEDLINE, and CINAHL electronic databases were comprehensively searched to extract the relevant studies published from inception to May 2022. A total of sixteen relevant studies (4907 participants) were identified and included in this review. Of these, twelve studies were from Asia, while four of the studies were conducted in Africa. The overall meta-analysis result found no significant association, although some of the studies confirmed an association between mycotoxin-linked mutations and primary liver cancer risk. Mainly, the experimental studies have shown associations between mycotoxin-linked mutations and cancer risk, and there is a need for researchers to confirm these links in epidemiological studies in order to guide public health policies and interventions.
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The Effect of Resveratrol on Blood Lipid Profile: A Dose-Response Meta-Analysis of Randomized Controlled Trials.
Cao, X, Liao, W, Xia, H, Wang, S, Sun, G
Nutrients. 2022;14(18)
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It is well known that cardiovascular disease is a leading cause of death. Imbalances in the blood lipid levels, such as elevation of total cholesterol, Triglycerides and LDL cholesterol, may increase the risk of cardiovascular disease. It has been shown that resveratrol, a polyphenol found in grapes, blueberries, mulberries, raspberries, peanuts, and knotweeds, has protective effects against cardiovascular disease. In this meta-analysis, 17 randomised controlled trials were included, with varying durations of 4 to 48 weeks and intervention dosages ranging from 10 to 3000 mg/day. According to the results of this meta-analysis, Resveratrol supplementation significantly reduced total cholesterol, triglycerides, and LDL cholesterol, but not HDL cholesterol. In addition, the reduction in LDL cholesterol was more significant in type 2 diabetic patients when resveratrol was supplemented for 12 weeks or more. A crucial factor in determining the effectiveness of resveratrol supplementation is its dosage. High doses over 500 mg/day were found to have the opposite effect of increasing body mass index and body weight and suppressing the cardioprotective effect. The effects of different dosages and durations of resveratrol supplementation on cardiometabolic health require further robust research. Healthcare professionals may use the results of this study to understand the importance of careful consideration when supplementing resveratrol as a nutraceutical.
Abstract
(1) Background: The effects of resveratrol on blood lipids are controversial. Whether there is a dose-response of the lipid profile upon resveratrol supplementation is unknown. (2) Methods: This dose-response meta-analysis of randomized controlled trials (RCTs) was performed to explore the effects of resveratrol supplementation on lipid profile. A systematical and comprehensive search of several databases was conducted by 30 June 2022. (3) Results: The results indicated that the intake of resveratrol could significantly decrease the total cholesterol (TC) (mean difference = -10.28; 95%CI: -13.79, -6.76, p < 0.001), triglyceride (TG) (Mean difference = -856; 95%CI: -12.37, -4.75, p < 0.001) and low-density lipoprotein cholesterol (LDL-C) (mean difference = -5.69; 95%CI: -11.07, -0.31, p = 0.038) level, but did not alter the level of high-density lipoprotein cholesterol (HDL-C). In the non-linear dose-response analysis, we observed a significant effect of the supplementation dosage on the level of LDL-C (p-nonlinearity = 0.002). Results from the sub-group analysis showed that the reduction of LDL-C was more significant in the trials with a duration of ≥12 weeks and in subjects with type 2 diabetes mellitus. (4) Conclusion: Findings from this study suggest that resveratrol may be beneficial to reduce TC, TG, and LDL-C levels in the blood. The dosage of the resveratrol intervention is an essential factor that affects the level of LDL-C.
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3.
Effect of Intermittent Fasting Diet on Glucose and Lipid Metabolism and Insulin Resistance in Patients with Impaired Glucose and Lipid Metabolism: A Systematic Review and Meta-Analysis.
Yuan, X, Wang, J, Yang, S, Gao, M, Cao, L, Li, X, Hong, D, Tian, S, Sun, C
International journal of endocrinology. 2022;2022:6999907
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The prevalence of obesity and metabolic syndrome may increase the risk of cardiovascular disease (CVD), diabetes, and neurological conditions. The imbalance in glucose and lipid metabolism and hypertension characterises the development of these chronic diseases. Intermittent fasting (IF) has been considered an effective dietary strategy for reducing the risk of obesity, insulin resistance, dyslipidaemia, diabetes, and CVD. This systematic review and meta-analysis include ten randomised controlled trials to evaluate the effects of IF intervention on glucose and lipid metabolism in people with metabolic syndrome. IF intervention regulated glucose metabolism by improving fasting blood glucose, glycosylated haemoglobin, insulin, and insulin resistance. IF intervention also positively impacted the body mass index and waist circumference. The total cholesterol, low-density lipoprotein levels, and triglyceride levels also improved, followed by the IF, showing the impact on lipid metabolism. Further robust studies are required due to heterogeneity between the included studies in type of IF, duration, the health status of participants, ethnicity, and outcome measurements. However, healthcare professionals can use the results of this systematic review and meta-analysis to understand the therapeutic effect of IF intervention on glycolipid metabolism in people with metabolic syndrome.
Expert Review
Conflicts of interest:
None
Take Home Message:
- IF does not require calorie restriction which may result in greater compliance
- IF does not restrict macronutrients such as CHO and fats, so may avoid the exclusion of key nutrients e.g. healthy fats and wholegrains.
- IF may have fewer adverse effects on daily routines and quality of life, which may mean adherence is easier.
- Improved glucose and lipid metabolism may prevent the development of chronic health conditions such as T2D, CVD and cancer.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Management of glucose and lipid metabolism can be achieved through weight reduction using dietary interventions such as very low calorie or CHO diets, which may be effective but difficult to sustain long term. An alternative approach for weight management, improved insulin resistance and subsequent prevention of comorbitities e.g. Type 2 Diabetes (T2D), Cardiovascular Disease (CVD) and cancer, is Intermittent Fasting (IF). such as time restricted or periodic fasting.
This study summarises the effects of IF dietary interventions lasting less than three months in overweight and obese women with Metabolic Syndrome, defined as the presence of any metabolic dysfunction including obesity, hyperglycaemia, dyslipidaemia or hypertension.
The meta-anlaysis was carried out following PRISMA guidelines. A literature search in PubMed and Medline using the keywords obesity/overweight, IF diet, metabolic syndrome, RCT’s and humans resulted in 10 studies with 12 types of intervention for analysis. The following outcomes were evaluated: glucose and lipid metabolism, insulin resistance, weight loss and blood pressure.
Results were analysed in R software using mean differences and 95% confidence intervals, and either random or fixed effects depending on the Cochrane’s Q and I(2) statistics. Funnel plots were inspected for potential bias and Egger’s regression tests for publication bias.
There were significant differences before and after the interventions for all glucose and lipid metabolism markers as well as body weight and systolic blood pressure :
Glucose metabolism:
- Fasting glucose reduced by 0.15mmol/L
- Insulin plasma reduced by 13.25uUI
- HbA1c reduced by 0.08%
- HOMA-IR (insulin resistance index) reduced by 0.31 on average
Lipid metabolism:
- Total cholesterol reduced by 0.32mmol/L
- LDL reduced by 0.22mmol/L
- Triglyceride reduced by 0.04mmol/L
Weight loss:
- Body weight reduced by 1.87kg
- BMI reduced by 0.8kg/m2
- Waist circumference reduced by 2.08cm
Blood pressure:
- Systolic reduced by 2.58mmHg
- Diastolic reduced by 3.12mmHg
Despite limitations of the meta-analysis, this study demonstrates IF has therapeutic effects on those with disordered lipid and glucose metabolism, and may prove to be an effective and sustainable approach.
Clinical practice applications:
- IF may be an effective alternative to restricted calorie or CHO diets for weight management with the associated benefits of glucose and lipid metabolism.
- IF has been shown to have therapeutic effects on individuals with impaired glucose and lipid metabolism.
- IF may be considered as a sustainable lifestyle choice rather than a ‘weight loss’ programme such as a very low calorie diet, which can result in poor quality of life and subsequent reduced adherence.
- Since it may take time for impaired glucose and lipid metabolism to progress to more serious disease states, establishing IF as an early intervention, may be considered as a prudent form of preventative medicine.
- IF has shown to have other health benefits such as reduced blood pressure and may be considered as adjuvant therapy.
Considerations for future research:
- Compares the effects of IF on different ethnicities, sex and age categories
- Evaluates the effect of IF on other disease states e.g. cancer, auto-immune conditions
- Assesses the response of other biomarkers e.g. inflammatory cytokines
- Compares different types and durations of IF on health biomarkers (eg periodic, time restricted)
Abstract
The question of whether or not intermittent fasting diets improve the clinical indicators of glycolipid metabolism remains unclear. This study systematically reviewed the relevant clinical trials to evaluate the effects of intermittent fasting diet on glucose and lipid metabolism and insulin sensitivity in patients with metabolic syndrome. To evaluate the effect of intermittent fasting diet intervention on patients with disorders of glucose and lipid metabolism, random-effect or fixed-effect meta-analysis models were used to calculate the average difference before and after intermittent fasting diet intervention and the corresponding 95% confidence intervals (CIs). After intermittent fasting diet intervention, in terms of glucose metabolism, fasting blood glucose reduced by 0.15 mmol/L (95% CI: -0.23; -0.06), glycosylated hemoglobin reduced by 0.08 (95% CIs: -0.25; -0.10), insulin plasma levels reduced by 13.25 uUI (95% CIs: -16.69; -9.82), and HOMA-IR decreased by 0.31 on an average (95% CIs: -0.44; -0.19). In addition, BMI decreased by 0.8 kg/m2 (95% CIs: -1.32; -0.28), body weight reduced by 1.87 kg (95% CIs: -2.67; -1.07), and the waist circumference decreased by 2.08 cm (95% CIs: -3.06; -1.10). Analysis of lipid metabolism showed that intermittent fasting diet intervention effectively reduced the total cholesterol level by 0.32 mmol/L (95% CIs: -0.60; -0.05), low-density lipoprotein level by 0.22 mmol/L (95% CIs: -0.37; -0.07), and triglyceride level by 0.04 mmol/L (95% CIs: -0.15; -0.07). Intermittent fasting diets have certain therapeutic effects on blood glucose and lipids in patients with metabolic syndrome and significantly improve insulin resistance. It may be considered as an auxiliary treatment to prevent the occurrence and development of chronic diseases.
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Effectiveness of wearable activity trackers to increase physical activity and improve health: a systematic review of systematic reviews and meta-analyses.
Ferguson, T, Olds, T, Curtis, R, Blake, H, Crozier, AJ, Dankiw, K, Dumuid, D, Kasai, D, O'Connor, E, Virgara, R, et al
The Lancet. Digital health. 2022;4(8):e615-e626
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A sedentary or physically inactive lifestyle significantly contributes to non-communicable diseases such as coronary heart disease, type 2 diabetes and stroke. Wearable activity trackers are low-cost solutions that encourage users to engage in physical activity. This umbrella review of systematic reviews and meta-analyses investigated the benefits of wearable activity trackers in improving physical activity levels and their beneficial effects on physiological and psychosocial outcomes. This umbrella review included thirty-nine systematic reviews, of which twenty-five systematic reviews included meta-analyses of the benefits of wearable trackers on physical activity levels. Results of this umbrella review suggest that wearable trackers increased physical activity levels, especially daily steps count and energy expenditure. The physiological outcomes included improvements in BMI, blood pressure, cholesterol, glycosylated haemoglobin, waist circumference, and body weight. There was also a slight improvement in the quality of life of the participants who used wearable activity trackers. Further robust studies are required to evaluate the effects of wearable trackers on the psychosocial outcomes in people with mental illness. However, healthcare professionals can use the results of this study to understand the impact of wearable trackers on physiological and psychosocial effects in a non-clinical population.
Abstract
Wearable activity trackers offer an appealing, low-cost tool to address physical inactivity. This systematic review of systematic reviews and meta-analyses (umbrella review) aimed to examine the effectiveness of activity trackers for improving physical activity and related physiological and psychosocial outcomes in clinical and non-clinical populations. Seven databases (Embase, MEDLINE, Ovid Emcare, Scopus, SPORTDiscus, the Cochrane Library, and Web of Science) were searched from database inception to April 8, 2021. Systematic reviews of primary studies using activity trackers as interventions and reporting physical activity, physiological, or psychosocial outcomes were eligible for inclusion. In total, 39 systematic reviews and meta-analyses were identified, reporting results from 163 992 participants spanning all age groups, from both healthy and clinical populations. Taken together, the meta-analyses suggested activity trackers improved physical activity (standardised mean difference [SMD] 0·3-0·6), body composition (SMD 0·7-2·0), and fitness (SMD 0·3), equating to approximately 1800 extra steps per day, 40 min per day more walking, and reductions of approximately 1 kg in bodyweight. Effects for other physiological (blood pressure, cholesterol, and glycosylated haemoglobin) and psychosocial (quality of life and pain) outcomes were typically small and often non-significant. Activity trackers appear to be effective at increasing physical activity in a variety of age groups and clinical and non-clinical populations. The benefit is clinically important and is sustained over time. Based on the studies evaluated, there is sufficient evidence to recommend the use of activity trackers.
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5.
Buckwheat and Cardiometabolic Health: A Systematic Review and Meta-Analysis.
Llanaj, E, Ahanchi, NS, Dizdari, H, Taneri, PE, Niehot, CD, Wehrli, F, Khatami, F, Raeisi-Dehkordi, H, Kastrati, L, Bano, A, et al
Journal of personalized medicine. 2022;12(12)
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Buckwheat is a gluten-free, pseudo-grain rich in bioactive compounds that are cardiometabolic health protective. Bioactive cardioprotective compounds include proteins, fibre, and polyphenols such as rutin and quercetin-3-glucoside. This systematic review and meta-analysis investigated the supplementation and consumption of buckwheat and its effects on cardiovascular risk markers. Sixteen studies were included in the systematic review, and ten were included in the meta-analysis. This systematic review and meta-analysis showed a modest, non-significant improvement in total cholesterol and glucose levels. Further robust studies are required to investigate the beneficial effects of bioactive compounds found in buckwheat due to the high heterogeneity of the included studies and the poor quality of the included studies. However, healthcare professionals can use the results of this research to understand the potential of buckwheat in improving or maintaining cardiometabolic health.
Abstract
Buckwheat (BW) is suggested to have beneficial effects, but evidence on how it affects cardiometabolic health (CMH) is not yet established. We aimed to assess the effects of BW and/or its related bioactive compounds on cardiovascular disease (CVD) risk markers in adults. Five databases were searched for eligible studies. Observational prospective studies, nonrandomized or randomized trials were considered if they assessed BW, rutin or quercetin-3-glucoside intake and CVD risk markers. We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for reporting. We selected 16 human studies based on 831 subjects with mild metabolic disturbances, such as hypercholesterolemia, diabetes and/or overweight. Eight studies, investigating primarily grain components, were included in the meta-analyses (n = 464). High study heterogeneity was present across most of our analyses. Weighted mean difference (WMD) for subjects receiving BW supplementation, compared to controls, were - 0.14 mmol/L (95% CI: -0.30; 0.02) for total cholesterol (TC), -0.03 mmol/L (95% CI: -0.22; 0.16) for LDL cholesterol, -0.14 kg (95% CI: -1.50; 1.22) for body weight, -0.04 mmol/L (95% CI: - 0.09;0.02) for HDL cholesterol, -0.02 mmol/L (95% CI: -0.15; 0.11) for triglycerides and -0.18 mmol/L (95% CI: -0.36; 0.003) for glucose. Most of the studies (66.7%) had concerns of risk of bias. Studies investigating other CVD markers were scarce and with inconsistent findings, where available. Evidence on how BW affects CMH is limited. However, the available literature indicates that BW supplementation in mild dyslipidaemia and type 2 diabetes may provide some benefit in lowering TC and glucose, albeit non-significant. Our work highlights the need for more rigorous trials, with better methodological rigor to clarify remaining uncertainties on potential effects of BW on CMH and its utility in clinical nutrition practice.
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The Effect of Walnut Intake on Lipids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Alshahrani, SM, Mashat, RM, Almutairi, D, Mathkour, A, Alqahtani, SS, Alasmari, A, Alzahrani, AH, Ayed, R, Asiri, MY, Elsherif, A, et al
Nutrients. 2022;14(21)
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The prevalence of cardiovascular disease increases as the modifiable risk factors increase, such as metabolic syndrome, obesity, type 2 diabetes, dyslipidaemia, and high blood pressure. Walnuts are a rich source of anti-inflammatory polyunsaturated fatty acids and omega-3 fatty acids. Walnuts are also known for their antioxidant properties and have been found to improve dyslipidaemia by reducing total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-c). This systematic review and meta-analysis of thirteen randomised controlled trials evaluated the effects of walnut intake on lipid profile. Most of the included studies used walnut dosage ranging from 15 g to 99 g/day for six to sixteen weeks of intervention. The results of this systematic review and meta-analysis showed significant improvements in TC, LDL-c, and triglyceride (TG) levels. Subgroup analysis revealed greater improvement in TC, LDL-c, and TG in overweight and other comorbidities but had normal levels of TC and LDL-C. Additionally, female participants showed greater improvements in TG levels, followed by the walnut intervention. Intervention duration also affected the beneficial effect of the walnut intervention. Further robust studies are required to determine the effects of walnut intake on cardiovascular disease risk reduction due to the high heterogeneity between the included studies. However, healthcare professionals can use the results of this research to understand the benefits of including walnuts as part of a healthy diet and their impact on reducing dyslipidaemia.
Abstract
Cardiovascular diseases (CVD) are the leading causes of death worldwide. Dyslipidemia is a cardiometabolic risk factor of CVD, yet it can be modifiable. Walnuts have been suggested as a dietary intervention to improve the lipid profile. Therefore, we reviewed the literature to assess the evidence linking walnut intake to the improvement of blood lipids, including total cholesterol (TC), low-density lipoprotein (LDL-C) cholesterol, high-density lipoprotein (HDL-C) cholesterol, and triglycerides (TG). PubMed and Embase databases were searched from 2010 up to March 2022. We limited our search to randomized controlled trials conducted on humans and published in English during the specified period. Cochrane's risk of bias tool for interventional studies was used. A random-effects model was used for the meta-analysis, and weighted mean differences were obtained (WMD) Thirteen trials from the U.S., Europe, and Asia were included. Walnut intake was associated with significant reductions in TC (WMD: -8.58 mg/dL), LDL-C (WMD: -5.68 mg/dL), and TG (WMD: -10.94 mg/dL). Walnut consumption was not associated with HDL-C. Subgroup analysis showed that overweight/obese and those with comorbidities had more lipid improvement. A longer trial duration did result in further improvements. However, our results may be prone to bias due to extraneous confounding factors. Additionally, levels of heterogeneity were considerable for some outcomes of interest. Results from this meta-analysis provide evidence for the health benefits of walnuts on blood lipids. Walnuts possibly reduce the risk of CVD; thus, they can be successfully added to a dietary pattern to enhance health benefits.
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7.
Effects of Oat Beta-Glucan Intake on Lipid Profiles in Hypercholesterolemic Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Yu, J, Xia, J, Yang, C, Pan, D, Xu, D, Sun, G, Xia, H
Nutrients. 2022;14(10)
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Dyslipidaemia is one of the risk factors associated with cardiovascular disease. Beta-glucan is a viscous soluble fibre found in microalgae, fungi and grains like oats, barley, sorghum etc. This systematic review and meta-analysis included thirteen randomised controlled trials to evaluate the effectiveness of oat beta-glucans on the lipid profiles of patients with hypercholesterolemia. This research showed a significant reduction in total cholesterol and low-density lipoprotein levels in hypercholesterolemic adults after beta-glucan intake. However, beta-glucans did not impact triglyceride and high-density lipoprotein cholesterol. Beta-glucan's effect on lipid profiles depended on the severity of hypercholesterolemia, the duration of the intervention, the source of beta-glucan, and the dosage of beta-glucan. Healthcare professionals can use the results of this study to understand the lipid profile-improving effects of beta-glucans in adults with moderate hypercholesterolemia. However, further robust studies are required to evaluate the effects of beta-glucan on lipid profiles and how the effect is affected by gender differences.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Consumption of oat beta glucans may be beneficial for improving total cholesterol and LDL-c in people with mild and moderate hypercholesterolemia
- The U.S Food and Drug Administration (FDA) recommends 3g or more of oat beta glucans per day to reap the benefits. This could be from 90g of oats (3 x 30g portions) or 1 30g portion of oats, 3 oatcakes and 1-2 tbsp of oat bran.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Authors highlight that Hypercholesterolemia is a risk factor for cardiovascular disease and a symptom of Metabolic Syndrome. Hypercholesterolemia commonly includes; elevated levels of total cholesterol and low-density lipoprotein cholesterol (LDL-c) and lower levels of high-density lipoprotein cholesterol (HDL-c).
Conventional medical treatment for hypercholesterolemia is statins, however, statins can have a number of adverse side effects. For this reason, dietary interventions have been investigated including the use of oat beta-glucans for their potential lipid lowering effects.
The aim of this systematic review and meta-analysis was to synthesise and evaluate the evidence for the effects of oat beta-glucans on serum cholesterol and triglyceride (TG) levels in adults with hypercholesterolemia.
Thirteen randomised controlled trials (RCTs) published between 1999 – 2021 met the study inclusion criteria. These studies included a total population of 927 people aged between 38-76 years and from 7 different countries worldwide. The majority of participants were diagnosed with mild hypercholesterolemia.
Participants were randomised into an intervention group receiving dietary sources of oat beta-glucans or food with added oat beta-glucans or a placebo control group consisting of diets without beta-glucans.
Study lengths ranged from 3 to 8 weeks with doses of oat beta-glucans between 1.5g to 6g. The studies were also broken down into sub-groups for high and low doses of oat beta-glucan and mild and moderate hypercholesterolemia.
Baseline and endpoint cholesterol (total cholesterol C, HD-c & LDL-c) and triglycerides were used to assess the effectiveness of the interventions and a weighted mean difference (WMD) calculated with a 95% confidence interval (CI).
Key Findings:
- a reduction in total cholesterol (WMD = -0.24mmol/L; 95% CI)
- a reduction in LDL-c (WMD = -0.27mmol/L; 95% CI )
- Sub-groups found that oat beta-glucans reduced serum TG levels in patients with moderate hypercholesterolemia (WMD = -0.11 mmol/L; 95% CI) but not in cases of mild hypercholesterolemia. (WMD = -0.01 mmol/L; 95% CI)
- Higher daily doses of oat beta glucans had more positive effects on TG levels, however the results were not statistically significant in this meta-analysis
- <3g WMD -0.11 mmol/L; 95% CI: -0.13 to -0.08 mmol/L
- >3g WMD -0.00 mmol/L; 95% CI: -0.16 to -0.16 mmol/L
- Greater reductions in HDL -c were found in patients with moderate hypercholesterolemia (WMD-0.06 mmol/L; 95% CI; -0.07 to -0.05 mmol/L) compared to mild cases (WMD-0.01 mmol/L; 95% CI; -0.08 to -0.10 mmol/L).
Conclusion
Dietary intake of oat beta-glucans may support the reduction of total cholesterol and low density lipoprotein cholesterol, however, no significant changes were found for high density lipoprotein cholesterol or serum triglycerides. Due to the heterogeneity between studies and inconsistencies in results, more trials are needed with larger sample sizes and longer durations.
Notes: The authors reported no conflicts of interest.
Clinical practice applications:
Based on the pooled results of this meta-analysis:
- 1.5g -6g of dietary intake of oat beta-glucans could support a reduction of TC and LDL-c in cases of mild and moderate hypercholesterolemia
- Intake of oat beta glucans >3g may reduce TG levels
- HDl -c may be improved with oat beta glucan intake of between 1.5g to 6g for clients with moderate hypercholesterolemia.
Considerations for future research:
The findings of 8 of the 13 RCTs indicated that when compared to the control group, LDL-c could be lowered by oat beta-glucans whilst the other 5 trials did not. However, the cumulative results of this meta analysis found a reduction in LDL-c.
There were also several limitations to this study:
- Heterogeneity between studies and inconsistent results
- Short study duration
- Small populations and limited sample size
- The results varied for different levels of hypercholesterolemia
- Results may also differ by sex and source of oat beta glucans
Larger and longer trials are therefore needed to confirm the results.
Abstract
(1) Background: hyperlipidemia is one of the cardiovascular diseases which becomes a great threat to the health of people worldwide. Oat beta-glucan is reported to have a beneficial effect on lowering blood lipids. To probe the effect of oat beta-glucan consumption on serum lipid profiles (total cholesterol, total triglyceride, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol), we carried out a systematic search on randomized controlled trials of oat beta-glucan intervention on hypercholesterolemic individuals. (2) Methods: the pieces of literature were obtained from PubMed, Scopus, Cochrane Library, Web of Science, and the Embase from inception to 28 February 2022. The results were presented with the weighted mean difference (WMD) with a 95% CI. The random-effects or fixed-effects model was applied according to the heterogeneity. The subgroup analysis and meta-regression were used to identify the source of heterogeneity. (3) Results: thirteen trials with 927 participants were included in our meta-analysis. Overall, oat beta-glucan supplementation significantly reduced levels of TC (pooled WMD = -0.24 mmol/L; 95%CI: -0.28 to -0.20 mmol/L), LDL-c (pooled WMD = -0.27 mmol/L; 95%CI: -0.35 to -0.20 mmol/L). Furthermore, beta-glucan consumption did not show significant effects on TG (pooled WMD = -0.04 mmol/L; 95%CI: -0.13 to 0.05 mmol/L), HDL-c (pooled WMD = 0.00 mmol/L; 95%CI: -0.05 to 0.05 mmol/L). Subgroup analysis indicated that critical factors, such as disease severity of participants, the daily intervention of oat beta-glucan, source of oat beta-glucan, and duration of intervention had impacts on outcomes. (4) Conclusions: oat beta-glucan intake may significantly decrease the level of TC and LDL-c while no significant changes in TG and HDL-c were observed. This meta-analysis supports the health benefits of oat beta-glucan, especially for its cholesterol-lowering features, although it has some inevitable limitations.
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Effect of vitamin D supplementation on cardiac-metabolic risk factors in elderly: a systematic review and meta-analysis of clinical trials.
Qorbani, M, Zarei, M, Moradi, Y, Appannah, G, Djalainia, S, Pourrostami, K, Ejtahed, HS, Mahdavi-Gorabi, A, Naderali, EK, Khazdouz, M
Diabetology & metabolic syndrome. 2022;14(1):88
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Modifiable risk factors such as dyslipidemia, hyperglycemia, obesity, and hypertension are characteristics of cardio-metabolic disorder which may lead to diabetes or cardiovascular disease. Previous research has shown an association between vitamin D deficiency and cardio-metabolic disorders. Studies have also shown that vitamin D deficiency is prevalent in older people. Therefore, this systematic review and meta-analysis evaluated the beneficial effects of Vitamin D supplementation (VDS) on the cardio-metabolic profile in elderly people. Twelve studies are included in this systematic review and meta-analysis. VDS dosage ranged from 400 IU/day to 4000 IU/day generally in most of the included studies, and the duration of intervention ranged from two months to one year. This systematic review and meta-analysis showed an improvement in total cholesterol and triglycerides followed by VDS in elderly participants. The subgroup analysis revealed improved glycaemic indices in elderly people with glycaemic irregularities. Longer-term VDS intervention improved glycaemic control. Further robust studies are required as there is high heterogeneity in the form of the vitamin D, dosage, duration, route of administration and study design of the included studies in this research. However, healthcare professionals can use the results of this study to understand the therapeutic value of VDS in improving the cardio-metabolic health of elderly people.
Abstract
BACKGROUND There has been a longstanding interest in the potential effect of vitamin D in preventing cardiac-metabolic diseases. However, there are divergent results regarding the impact of vitamin D supplementation (VDS) on managing cardiac-metabolic outcomes in the elderly population. MATERIAL AND METHOD We systematically searched electronic databases; Web of Science, PubMed, Scopus, EMBASE, Cochrane, and ProQuest. We included all trials that evaluated the effect of VDS on cardiac-metabolic risk factors in the elderly population, which were published until 30 September 2021. The effects of VDS on cardiac-metabolic outcomes were assessed using standardized mean difference (SMD). A random-effect model was used to pool the SMD and 95% confidence interval (CI). RESULT The literature search identified 4409 studies, of which 12 trials met inclusion criteria. Results of random effect meta-analysis indicated a significant reduction in total cholesterol (TC) (SMD: - 0.14 mg/dl; 95% CI: - 0.25, - 0.02) and triglyceride (TG) (SMD: - 0.45 mg/dl; 95% CI: - 0.86, - 0.04) with VDS compared to the placebo. The subgroup analyses revealed that the reduction of TG in patients with diabetes and vitamin D deficiency was significant. Furthermore, short-term intervention (≤ 6 months) induced a significantly lower level of TG and insulin in comparison to longer duration (> 6 months). CONCLUSION The study suggests that VDS could improve insulin concentration and dyslipidemia in the elderly population. The systematic review was registered in Alborz university of medical sciences with 2060-01-03-1397 number and the Ethics council IR.ABZUMS.REC.1397.207 number.
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Effects of the Treatment with Flavonoids on Metabolic Syndrome Components in Humans: A Systematic Review Focusing on Mechanisms of Action.
Gouveia, HJCB, Urquiza-Martínez, MV, Manhães-de-Castro, R, Costa-de-Santana, BJR, Villarreal, JP, Mercado-Camargo, R, Torner, L, de Souza Aquino, J, Toscano, AE, Guzmán-Quevedo, O
International journal of molecular sciences. 2022;23(15)
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Metabolic syndrome is a condition characterised by at least three of the five risk factors, such as abdominal obesity, elevated fasting glucose, blood pressure and triglycerides and reduced high-density lipoprotein cholesterol (HDL-c). There is a strong link between metabolic syndrome and the development of cardiovascular disease and Type 2 diabetes. Research suggests that increasing consumption of flavonoid-rich foods can be beneficial in reducing cardiovascular morbidity and mortality. Flavonoids are bioactive compounds that possess antioxidative, anti-inflammatory, anti-cancerous, anti-mutagenic, and enzymatic properties. This systematic review of 29 randomised controlled trials evaluated the beneficial effects of long-term flavonoid supplementation in reducing the risk factors of metabolic syndrome. This review included a variety of flavonoid supplements, such as anthocyanin, hesperidin, quercetin, epigallocatechin gallate (egcg), genistein, theaflavin, catechin, and eriocitrin. Additionally, this research investigated the mechanisms behind the beneficial effects of flavonoid supplementation. Results showed that flavonoid supplementation for at least three weeks improved metabolic parameters and inflammatory markers, with hesperidin showing the greatest improvements in metabolic parameters. Healthcare professionals can use these findings to understand the potential benefits of long-term flavonoid supplementation in improving metabolic parameters. However, more robust studies are needed to determine the therapeutic dosages of different flavonoids.
Abstract
Diets high in bioactive compounds, such as polyphenols, have been used to mitigate metabolic syndrome (MetS). Polyphenols are a large group of naturally occurring bioactive compounds, classified into two main classes: non-flavonoids and flavonoids. Flavonoids are distributed in foods, such as fruits, vegetables, tea, red wine, and cocoa. Studies have already demonstrated the benefits of flavonoids on the cardiovascular and nervous systems, as well as cancer cells. The present review summarizes the results of clinical studies that evaluated the effects of flavonoids on the components of the MetS and associated complications when offered as supplements over the long term. The results show that flavonoids can significantly modulate several metabolic parameters, such as lipid profile, blood pressure, and blood glucose. Only theaflavin and catechin were unable to affect metabolic parameters. Moreover, only body weight and body mass index were unaltered. Thus, the evidence presented in this systematic review offers bases in support of a flavonoid supplementation, held for at least 3 weeks, as a strategy to improve several metabolic parameters and, consequently, reduce the risk of diseases associated with MetS. This fact becomes stronger due to the rare side effects reported with flavonoids.
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The Gut Microbiota (Microbiome) in Cardiovascular Disease and Its Therapeutic Regulation.
Rahman, MM, Islam, F, -Or-Rashid, MH, Mamun, AA, Rahaman, MS, Islam, MM, Meem, AFK, Sutradhar, PR, Mitra, S, Mimi, AA, et al
Frontiers in cellular and infection microbiology. 2022;12:903570
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Cardiovascular disease (CVD) accounts for 31% of all-cause mortality worldwide. Irregularities in the composition of intestinal microbial composition, genetic factors, nutrition, metabolic irregularities, and smoking are among the potential causes of CVD. Intestinal permeability and translocation of endotoxins and bacterial metabolites to systemic circulation may trigger an immune response and inflammation, which may increase the risk of CVD. Synthesis of bacterial metabolites such as trimethylamine N-oxide (TMAO) by choline-inducing gut bacteria and reduced consumption of dietary TMAO precursors may elevate the CVD risk. This review explores the latest research on the role of gut microbiota in the development of atherosclerosis and CVD, as well as potential strategies to prevent CVD by targeting TMAO-producing gut bacteria. Elevated levels of TMAO in the bloodstream can lead to the buildup of cholesterol and ultimately result in atherosclerosis. However, consuming probiotics and fibre-rich foods can help regulate gut bacteria, reduce inflammation, and improve lipid profiles, all of which contribute to better cardiovascular health. More future robust studies are required to examine the mechanistic insights and confirm whether TMAO can serve as a biomarker for preventing CVD through the therapeutic modulation of intestinal bacteria.
Abstract
In the last two decades, considerable interest has been shown in understanding the development of the gut microbiota and its internal and external effects on the intestine, as well as the risk factors for cardiovascular diseases (CVDs) such as metabolic syndrome. The intestinal microbiota plays a pivotal role in human health and disease. Recent studies revealed that the gut microbiota can affect the host body. CVDs are a leading cause of morbidity and mortality, and patients favor death over chronic kidney disease. For the function of gut microbiota in the host, molecules have to penetrate the intestinal epithelium or the surface cells of the host. Gut microbiota can utilize trimethylamine, N-oxide, short-chain fatty acids, and primary and secondary bile acid pathways. By affecting these living cells, the gut microbiota can cause heart failure, atherosclerosis, hypertension, myocardial fibrosis, myocardial infarction, and coronary artery disease. Previous studies of the gut microbiota and its relation to stroke pathogenesis and its consequences can provide new therapeutic prospects. This review highlights the interplay between the microbiota and its metabolites and addresses related interventions for the treatment of CVDs.