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Soluble Fiber Supplementation and Serum Lipid Profile: A Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials.
Ghavami, A, Ziaei, R, Talebi, S, Barghchi, H, Nattagh-Eshtivani, E, Moradi, S, Rahbarinejad, P, Mohammadi, H, Ghasemi-Tehrani, H, Marx, W, et al
Advances in nutrition (Bethesda, Md.). 2023
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Dyslipidaemia is considered an important risk factor for cardiovascular disease incidence, characterised by elevated circulating concentrations of blood lipids such as cholesterol and triglycerides (TG). Dietary fibre, particularly water-soluble fibres, has demonstrated efficacy and tolerability in serum lipid management. The aim of this study was to synthesise data from individual investigations and to determine the overall treatment effect of soluble fibre on serum blood lipids. This study is a comprehensive systematic review and a dose-response meta-analysis of 181 studies with 220 treatment arms, including 14,505 participants (7348 cases and 7157 controls). Results show that soluble fibre supplementation improved serum TG, total cholesterol, low-density lipoprotein cholesterol, and apolipoprotein-B concentrations. However, it did not alter serum high-density lipoprotein cholesterol and apolipoprotein-A levels. Furthermore, the meta-analysis showed a significant effect of soluble fibre supplementation on serum TG, total cholesterol, and high-density lipoprotein cholesterol in 15 g/d and low-density lipoprotein cholesterol in 10 g/d. Authors conclude that increasing fibre intake using soluble fibre supplementation could be an effective intervention in the prevention and management of dyslipidaemia, and consequently may contribute to the risk reduction of cardiovascular diseases.
Abstract
To present a comprehensive synthesis of the effect of soluble fiber supplementation on blood lipid parameters in adults, a systematic search was undertaken in PubMed, Scopus, and ISI Web of Science of relevant articles published before November 2021. Randomized controlled trials (RCTs) evaluating the effects of soluble fibers on blood lipids in adults were included. We estimated the change in blood lipids for each 5 g/d increment in soluble fiber supplementation in each trial and then calculated the mean difference (MD) and 95% CI using a random-effects model. We estimated dose-dependent effects using a dose-response meta-analysis of differences in means. The risk of bias and certainty of the evidence was evaluated using the Cochrane risk of bias tool and the Grading Recommendations Assessment, Development, and Evaluation methodology, respectively. A total of 181 RCTs with 220 treatment arms (14,505 participants: 7348 cases and 7157 controls) were included. There was a significant reduction in LDL cholesterol (MD: -8.28 mg/dL, 95% CI: -11.38, -5.18), total cholesterol (TC) (MD: -10.82 mg/dL, 95% CI: -12.98, -8.67), TGs (MD: -5.55 mg/dL, 95% CI: -10.31, -0.79), and apolipoprotein B (Apo-B) (MD: -44.99 mg/L, 95% CI: -62.87, -27.12) after soluble fiber supplementation in the overall analysis. Each 5 g/d increase in soluble fiber supplementation had a significant reduction in TC (MD: -6.11 mg/dL, 95% CI: -7.61, -4.61) and LDL cholesterol (MD: -5.57 mg/dl, 95% CI: -7.44, -3.69). In a large meta-analysis of RCTs, results suggest that soluble fiber supplementation could contribute to the management of dyslipidemia and the reduction of cardiovascular disease risk.
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Plum supplementation and lipid profile: a systematic review and meta-analysis of randomised controlled trials.
Askarpour, M, Ghalandari, H, Setayesh, L, Ghaedi, E
Journal of nutritional science. 2023;12:e6
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The rate of nutrition-related non-communicable diseases is increasing worldwide. Lipid profile and its alterations have been used both as indicators of metabolic disorders and methods to evaluate patients’ response to dietary interventions. The aim of this study was to investigate the effectiveness of plums on improving parameters of lipid profile. This study is a systematic review and meta-analysis of nine randomised controlled trials with a total of eleven arms and 592 participants. Results show that plum can be beneficial in reducing triacylglycerols [triglycerides] in the unhealthy and low-density lipoprotein cholesterol in all individuals. However, no significant impact regarding blood triacylglycerols and high-density lipoprotein cholesterol levels, could be detected both in crude and subgroup analyses. Authors conclude that further clinical trials, taking advantage of a standard protocol of plum supplementation, should be conducted to elucidate the possible effect that plum supplementation might exert on lipid profile parameters.
Abstract
Plums are abundant in bioactive compounds which have been associated with numerous health benefits. In the present study, we aimed at examining the impact of plum supplementation on lipid profile of individuals. Electronic bibliographical databases were searched for relevant randomised clinical trials. Articles meeting our eligibility criteria were included for data extraction and final analysis. Weighted mean difference (WMD) was estimated using a random-effect model. Of the total articles retrieved in the initial search, nine articles were found to be eligible to be included in the analysis. Our results show that plum supplementation significantly improves total cholesterols levels in the unhealthy individuals. Moreover, plum supplementation reduces the LDL-c levels in the pooled sample (WMD = -11⋅52 mg/dl; 95 % CI -21⋅93, -1⋅11, P = 0⋅03, I 2 = 98⋅7 %) and also in some of the subgroups of individuals (dried plum, unhealthy subjects, duration more than 8 weeks). Moreover, it had a significant reducing effect on TC levels just in unhealthy subjects. Although plum supplementation did not have any significant impact on serum levels of TG nor HDL-c. Our results show that supplementation with plums is potentially effective in reducing serum total cholesterol and LDL-c.
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Effect of supplementation with Chlorella vulgaris on lipid profile in adults: A systematic review and dose-response meta-analysis of randomized controlled trials.
Sherafati, N, Bideshki, MV, Behzadi, M, Mobarak, S, Asadi, M, Sadeghi, O
Complementary therapies in medicine. 2022;66:102822
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Dyslipidaemia is a chronic metabolic disorder that is characterized by increased levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and reduced levels of high-density lipoprotein cholesterol (HDL-C). Patients with dyslipidaemia have an increased risk of coronary heart disease, stroke, non-alcoholic fatty liver disease, diabetes and even mortality. The aim of this study was to investigate the effect of Chlorella vulgaris supplementation on lipid profile in adults. This study is a systematic review and meta-analysis of ten randomised controlled trial studies. The studies included a total of 539 individuals (n= 264 in the Chlorella vulgaris group and n= 275 in the control group). Results show that Chlorella vulgaris supplementation resulted in a significant reduction in TC and LDL-C levels, while it had no significant effect on TG and HDL-C levels either in the overall analysis or in the subgroup analysis. Furthermore, the reducing effect of Chlorella vulgaris supplementation on LDL-C levels was significant between zero and 1500 mg/d and it was not significant at higher dosages. Authors conclude that future studies should examine the effect of Chlorella vulgaris supplementation on other biochemical parameters such as glycaemic measures and inflammatory biomarkers.
Abstract
OBJECTIVE To summarize available findings on the effect of Chlorella vulgaris supplementation on lipid profile in adults. DESIGN Systematic review and meta-analysis of randomized controlled trials (RCTs). SETTING This study followed 2020 PRISMA guideline. We performed a systematic search in the online databases to identify relevant articles and then, extracted required data from each paper for the meta-analysis. Random-effects models were used to obtain overall mean difference (MD) comparing Chlorella vulgaris supplementation with a control group. MAIN OUTCOME MEASURES Blood lipids including triglyceride (TG), total cholesterol (TC), LDL-C, and HDL-C. RESULTS In total, 10 RCTs with a total sample size of 539 adults (264 in the Chlorella vulgaris group and 275 in the control group) were included. Of the 10 RCTs, four had a low risk of bias for all aspects of the Cochrane risk of bias tool. Also, only two studies determined the chlorella content, purity, potency, and contamination of the supplements used in the intervention. Combining results from these studies showed a summary MD of -2.11 mg/dL (95% CI: -7.28 to 3.06) for TG, -7.47 mg/dL (95% CI: -12.98 to -1.96) for TC, -7.71 mg/dL (95% CI: -14.05 to -1.37) for LDL-C, and -0.45 mg/dL (95% CI: -0.67 to 1.57) for HDL-C, indicating a beneficial effect of Chlorella vulgaris supplementation on TC and LDL-C levels. Based on the dose-response analysis, the reducing effect of Chlorella vulgaris supplementation on LDL-C levels was seen at the dosages between zero and 1500 mg/d (P for non-linearity= 0.01), whereas in higher amounts, this effect was not significant. CONCLUSION We found that Chlorella vulgaris supplementation had a beneficial effect on TC and LDL-C levels with no significant effect on TG and HDL-C levels.
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The effects of olive leaf extract on cardiovascular risk factors in the general adult population: a systematic review and meta-analysis of randomized controlled trials.
Razmpoosh, E, Abdollahi, S, Mousavirad, M, Clark, CCT, Soltani, S
Diabetology & metabolic syndrome. 2022;14(1):151
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Modifiable unhealthy behaviours, such as sedentary lifestyle, smoking, and unhealthy food habits, are regarded as important contributors to the widespread prevalence of cardiovascular diseases (CVDs), which occur concurrently in overweight/obesity, hypertension, dyslipidaemia, hyperglycaemia, and inflammation. The aim of this study was to investigate whether olive leaf extract (OLE) could improve the major cardiovascular-related variables, including lipid profile, glucose haemostasis, blood pressure, as well as liver/kidney and inflammatory markers in the general adult population. This study is a systematic review and meta-analysis of twelve randomised controlled studies. Results show that OLE supplementation: - significantly decreased triglycerides and systolic blood pressure levels. - only had short-term positive effects on blood pressure and lipid profiles, which may be attributed to the active constituents in OLE. - had more profitable effects on the improvement of triglycerides, blood pressure, total cholesterol and low-density lipoprotein cholesterol measures among participants with hypertension and individuals with normal body weight. Authors conclude that stronger randomised controlled trial investigations, assessing different doses and durations of OLE, are required to better elucidate the effects of OLE supplementation.
Abstract
BACKGROUND The aim of this systematic review and meta-analysis was to determine the effect of olive leaf extract (OLE) supplementation on cardiovascular-related variables, including lipid, glycemic, inflammatory, liver and renal-related factors, as well as blood pressure. METHODS PubMed, ISI Web of Science, Scopus, and Cochrane library were searched, up to October 2021, for relevant controlled trials. Mean differences and standard deviations were pooled for all outcomes, using a random-effects model. The methodological quality, as well as quality of evidence were assessed using standard tools. RESULTS Twelve studies (n = 819 participants) were included in our analyses. Overall analyses showed that OLE supplementation significantly decreased triglyceride (TG) levels (WMD = - 9.51 mg/dl, 95% CI - 17.83, - 1.18; P = 0.025; I2 = 68.7%; P-heterogeneity = 0.004), and systolic blood pressure (SBP) (WMD = - 3.86 mmHg, 95% CI - 6.44, - 1.28 mmHg; P = 0.003; I2 = 19.9%; P-heterogeneity = 0.28). Subgroup analyses also revealed a significant improvement in SBP (- 4.81 mmHg) and diastolic blood pressure (- 2.45 mmHg), TG (- 14.42 mg/dl), total cholesterol (TC) (- 9.14 mg/dl), and low-density lipoprotein-C (LDL-C) (- 4.6 mg/dl) measurements, in patients with hypertension. Significant reductions were also observed in TC (- 6.69 mg/dl), TG (- 9.21 mg/dl), and SBP (- 7.05 mmHg) in normal-weight individuals. However, no meaningful changes were seen in glucose hemostasis, liver and kidney, or inflammatory markers. CONCLUSION The present study revealed that supplementation with OLE yielded beneficial effects for blood pressure and lipid profile in adults, especially in patients with hypertension. As the quality of evidence for glucose hemostasis variables, liver, kidney, and inflammatory markers, were low-to-very low, higher quality RCTs may impact the overarching results. This study was registered at PROSPERO with the code CRD42022302395.
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Do B Vitamins Enhance the Effect of Omega-3 Polyunsaturated Fatty Acids on Cardiovascular Diseases? A Systematic Review of Clinical Trials.
Zhu, J, Xun, PC, Kolencik, M, Yang, KF, Fly, AD, Kahe, K
Nutrients. 2022;14(8)
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Dietary intake of B-vitamins or omega-3 polyunsaturated fatty acids (PUFAs) has been found to be inversely related to cardiovascular disease (CVD). The aim of this study was to examine whether the combined supplementation of B-vitamins and omega-3 PUFAs could provide additional beneficial effects on improving risk factors to prevent CVD beyond the effects of either of them alone. This study is a systematic review of fifteen studies. The sample sizes ranged from 12 to 2501 participants with study duration ranging from 4 weeks to 4.7 years. Results show that the combined supplementation with B-vitamins and omega-3 PUFAs may be promising and more effective at reducing plasma homocysteine, triglycerides and low-density lipoprotein cholesterol than each supplementation alone. Authors conclude that: - there is no solid evidence that the joint supplementation of B-vitamins and omega-3 PUFAs can offer a synergistic effect on preventing CVD and decreasing the relevant morbidity and/or mortality in susceptible populations. - dietetic strategies for preventing CVD need to focus more on the importance of considering effects at the whole food and dietary patterns level. - further well-designed high-quality trials that will use the combined supplementation of B vitamins and omega-3 PUFAs or dietary patterns rich in these two types of nutrients are required.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Combined vitamin B and n3 PUFA supplementation might have favourable health effects
- Combined vitamin B and n3 PUFA supplementation could help in the primary and secondary prevention of cardiovascular disease
- The suggested favourable dose ranges are vitamin B6: 2.5–80 mg/day, vitamin B12: 20–1000 μg/day, folic acid: 150–10000 μg/day, and n3 PUFA 0.2–2) g/day.
Evidence Category:
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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:
- The paper reviews whether combined supplementation of vitamin B (B2, B6, B9, and B12) and omega-3 polyunsaturated fatty acids (n3 PUFA) outweighs the individual cardiovascular benefits of each supplement. Registered in PROSPERO under CRD42018085993
- A total of 15 clinical studies including 8,263 individuals published from December 2021, that investigated the combined effects of the supplements met inclusion criteria and were included in the review
- Although the results indicate the beneficial effects of combined supplementation in primary and secondary cardiovascular prevention, firm conclusions cannot be drawn from the existing data, and more studies are needed in this area.
Clinical practice applications:
In comparison with a single supplement alone, the combined administration of vitamin B and n3 PUFA might have:
- Hypolipidemic effects, by reducing triglycerides and LDL-cholesterol. Some of the studies indicate a lowering of LDL-c up to 13% and triglycerides up to 24%
- Anti-inflammatory effects, by reducing homocysteine. Based on some of the studies, the lowering effects might go up to 39%.
Dietary practice might benefit from the following:
- The authors highlighted food-based and healthy dietary pattern-based strategies should include food sources rich in these nutrients such as fish, vegetables, fruit, legumes, nuts, and eggs
- The authors conclude that intake of whole foods and whole diets rich in desirable foods (such as MedDiet) should be encouraged
- The supplementation dose ranges in the studies covered by the review were the following: vitamin B6: 2.5–80 mg/day, vitamin B12: 20–1000 μg/day, folic acid: 150–10000 μg/day and n3 PUFA 0.2–2) g/day
- Limitations of the systematic review include different supplementation regimens, variability of study designs in terms of duration of the intervention, existence of placebo group, dosages and the inability to monitor study subjects’ habitual diet.
Considerations for future research:
- Future studies should be designed regarding the need for a uniform methodological approach in testing the combined effects of vitamin B complex and n3 PUFA supplements
- The studies should investigate supplementation strategies and dietary patterns rich in both nutrients.
Abstract
Studies have suggested that B vitamins or omega-3 polyunsaturated fatty acids (PUFAs) may deter the development of cardiovascular disease (CVD). This systematic review aims to examine whether the combined supplementation of both B vitamins and omega-3 PUFAs could provide additional beneficial effects to prevent CVD beyond the effect of each supplement based on clinical trials published up to December 2021. The overall findings are inconsistent and inconclusive, yet the combined supplementation of these two nutrients may be more effective at reducing plasma homocysteine, triglyceride, and low-density lipoprotein-cholesterol than the individual components. The underlying mechanisms mainly include alleviating endothelial dysfunction, inhibiting atherosclerosis and lesion initiation, reducing oxidative stress, suppressing activation of pro-inflammatory cytokines, regulating endothelial nitric oxide synthase, and interfering with methylation of genes that promote atherogenesis. Although biologically plausible, the existing literature is insufficient to draw any firm conclusion regarding whether B vitamins can further enhance the potential beneficial effects of omega-3 PUFA intake on either primary or secondary prevention of CVD. The inconsistent findings may be largely explained by the methodological challenges. Therefore, well-designed high-quality trials that will use the combined supplementation of B vitamins and omega-3 PUFAs or dietary patterns rich in these two types of nutrients are warranted.
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Low-carbohydrate diets and men's cortisol and testosterone: Systematic review and meta-analysis.
Whittaker, J, Harris, M
Nutrition and health. 2022;28(4):543-554
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Testosterone is the primary male sex hormone, and vital for reproductive development and function. Moreover, low endogenous testosterone is associated with an increased risk of chronic disease, including type 2 diabetes and cardiovascular disease. The aim of this study was to investigate the effects of low- versus high-carbohydrate diets on mens' testosterone and cortisol. This study is a systematic review and meta-analysis of twenty-seven studies with a total of 309 participants. Twelve of these studies were randomised trials whilst the rest were non-randomised. Results show an increase in resting and post-exercise cortisol on short-term low-carbohydrate diets (<3 weeks). In fact, resting cortisol levels return to baseline after <3 weeks on a LC diet, whilst post-exercise cortisol remains elevated. Furthermore, high-protein diets cause a large decrease in resting total testosterone. Authors conclude that further research is required in order to warrant their findings.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Short-term LC-diets diets cause a moderate increase in resting and post-exercise cortisol however this effect is not seen in LC-diets followed for great than 3 weeks
- HP-LC diets caused a statistically significant decrease in resting TT, suggesting caution in relation to endocrine effects of LC diets
Evidence Category:
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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:
Introduction:
A systematic review and network meta-analysis was conducted on the effects of low-carbohydrate (LC) versus high-carbohydrate (HC) diets on men’s testosterone and cortisol.
The review was registered with PROSPERO and reported using PRISMA 2020 checklists.
Methods:
A comprehensive search strategy was used to find intervention studies looking at healthy adult males and LC diets of <35% carbohydrate. Studies were assessed for quality using the Cochrane Risk of Bias tool. Sub-group analyses was conducted for diet duration, protein intake and exercise duration.
Results:
The literature search resulted in 27 studies with a total of 309 healthy adult male participants, age: 27.3 ± 4.7 (to minimise variation in steroid hormone metabolism), body mass: 78.6± 7.1kg and BMI: 24.8 ±1.6. 12 randomised and 15 non-randomised controlled trials were analysed. 21 studies were considered low risk bias, 5 medium and 1 high risk.
- Short-term (<3 weeks) LC diets moderately increased resting cortisol (0.41 [0.16, 0.66], p < 0.01) when compared to HC diets.
- Long-term (≥3 weeks) LC diets had no consistent effect on resting cortisol
- LC diets resulted in higher post-exercise cortisol, after long-duration exercise (≥20 min): 0 h (0.78 [0.47, 1.1], p < 0.01), 1 h (0.81 [0.31, 1.31], p < 0.01), and 2 h (0.82 [0.33, 1.3], p < 0.01).
- The overall results for resting total testosterone (TT) showed a significant decrease on LC versus HC diets (SMD = −0.48, p = 0.01. However, subgroup analyses revealed this effect to be limited to high-protein (HP) LC diets, which yielded a very large decrease in TT (SMD = −1.08, p < 0.01; ∼5.23 nmol/L), albeit in a small sample (n = 26).
- Moderate protein (MP) (<35%), low-carbohydrate diets had no consistent effect on resting total testosterone, however high-protein (≥35%), low-carbohydrate diets greatly decreased resting (−1.08 [−1.67, −0.48], p < 0.01) and post-exercise total testosterone (−1.01 [−2, −0.01] p = 0.05).
- There was no overall effect of LC versus HC diets on 0 h post-exercise TT (SMD = −0.03, p = 0.95). However, subgroup analysis showed 0 h post-exercise was non-significantly higher on long-term LC versus HC diets (SMD = 0.44, p = 0.18), and much lower on short-term LC versus HC diets (SMD = −1.01, p = 0.05)
Conclusion:
This systematic review and metanalysis found an increase in resting and post-exercise cortisol on short-term LC diets. Cortisol does return to baseline in the first 3 weeks of a low-carbohydrate (LC) diet. The same response is, however, not seen in post-exercise cortisol, which remains elevated. In addition, the review showed that compared to moderate-protein diets, HP diets were found to cause a large decrease in resting and post-exercise TT (∼5.23 nmol/L).
Clinical practice applications:
The results of this review suggest that exercising whilst following a LC diet can increase cortisol in the short term, but not long-term. This suggests a period of diet adaptation. The effects of long-term LC diets on cardiovascular disease risk is uncertain and healthcare practitioners should monitor client responses and keep up-to-date with new research in this area
Since HP-LC diets were found to significantly decrease resting testosterone it highlights the need to ensure that protein intake does not exceed the urea cycle’s capacity due to potential adverse endocrine effects.
For clients where there is a desire to increase strength, power and hypertrophy, a MP-LC diet could be of benefit, as it showed potential to signal an increased anabolic state post exercise..
NB: Since the review only included a low number of studies and saw within these some heterogeneity that could not be explained, more research is needed before the paper’s findings can be conclusive. The above potential practice applications should therefore be seen as something to be mindful of when working with clients where cortisol and testosterone levels are relevant to their protocol.
Considerations for future research:
Future research should consider:
- Since LC diets have been shown to have a positive effect on health – decreased triglycerides, increased high density lipoprotein cholesterol and weight loss - future studies would benefit from including these markers so any positive and negative impacts can be monitored directly.
- Despite extensive analysis including sensitivity analysis to reduce bias and heterogeneity of the results, the paper highlights a need for further research to ensure consistency in key parameters e.g., exercise duration and intensity, carbohydrate supplements inclusion and period of dietary intervention. Since it was identified that HP-LP diets impact post exercise and resting TT, follow up studies would benefit from consistency in participants diets. This would help to reduce any potential confounding results.
Abstract
Background: Low-carbohydrate diets may have endocrine effects, although individual studies are conflicting. Therefore, a review was conducted on the effects of low- versus high-carbohydrate diets on men's testosterone and cortisol. Methods: The review was registered on PROSPERO (CRD42021255957). The inclusion criteria were: intervention study, healthy adult males, and low-carbohydrate diet: ≤35% carbohydrate. Eight databases were searched from conception to May 2021. Cochrane's risk of bias tool was used for quality assessment. Random-effects, meta-analyses using standardized mean differences and 95% confidence intervals, were performed with Review Manager. Subgroup analyses were conducted for diet duration, protein intake, and exercise duration. Results: Twenty-seven studies were included, with a total of 309 participants. Short-term (<3 weeks), low- versus high-carbohydrate diets moderately increased resting cortisol (0.41 [0.16, 0.66], p < 0.01). Whereas, long-term (≥3 weeks), low-carbohydrate diets had no consistent effect on resting cortisol. Low- versus high-carbohydrate diets resulted in much higher post-exercise cortisol, after long-duration exercise (≥20 min): 0 h (0.78 [0.47, 1.1], p < 0.01), 1 h (0.81 [0.31, 1.31], p < 0.01), and 2 h (0.82 [0.33, 1.3], p < 0.01). Moderate-protein (<35%), low-carbohydrate diets had no consistent effect on resting total testosterone, however high-protein (≥35%), low-carbohydrate diets greatly decreased resting (-1.08 [-1.67, -0.48], p < 0.01) and post-exercise total testosterone (-1.01 [-2, -0.01] p = 0.05). Conclusions: Resting and post-exercise cortisol increase during the first 3 weeks of a low-carbohydrate diet. Afterwards, resting cortisol appears to return to baseline, whilst post-exercise cortisol remains elevated. High-protein diets cause a large decrease in resting total testosterone (∼5.23 nmol/L).
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The effect of probiotics on gestational diabetes and its complications in pregnant mother and newborn: A systematic review and meta-analysis during 2010-2020.
Mahdizade Ari, M, Teymouri, S, Fazlalian, T, Asadollahi, P, Afifirad, R, Sabaghan, M, Valizadeh, F, Ghanavati, R, Darbandi, A
Journal of clinical laboratory analysis. 2022;36(4):e24326
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Gestational diabetes (GD) refers to glucose intolerance in pregnant women at 24–28 weeks without a history of diabetes that results in hyperglycaemia. Some studies suggest that probiotics are able to overcome insulin resistance in pregnant women with GD. The aim of this study was to investigate the inhibitory effects of probiotics supplementation on GD among pregnant women based on Randomized Controlled Trial studies during in the last 10 years (2010–2020). This study is a systematic review and meta-analysis of 28 studies. The age range of the pregnant women following the probiotics treatment was 18–40 years. Results show that taking probiotic supplements during pregnancy by women with GD has beneficial effects on the metabolic status, colostrum adiponectin levels, microbiome composition, and the maternal and infant health. However, 4 of the analysed studies did not find any significant effect for the probiotic intervention on the incidence of GD. Authors conclude that more homogeneous studies are needed to generalize the findings of this study. Thus, specific probiotic supplementation may be introduced as one of the adjuvant therapies for GD patients.
Abstract
This study was aimed to evaluate the effect of probiotics consumption on gestational diabetes (GD) and its complications in pregnant mother and newborn. The study was registered on PROSPERO (CRD42021243409) and all the enrolled articles were collected from four databases (Medline, Scopus, Embase, and Google Scholar) as randomized controlled trials (RCTs) from 2010 to 2020. A total of 4865 study participants from 28 selected studies were included in this review. The present meta-analysis showed that the consumption of probiotics supplementation has the potential to decrease GD-predisposing metabolic parameters such as blood glucose level, lipid profile, inflammation, and oxidative markers which may reduce GD occurrence among pregnant women.
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Non-Systematic Review of Diet and Nutritional Risk Factors of Cardiovascular Disease in Obesity.
Rychter, AM, Ratajczak, AE, Zawada, A, Dobrowolska, A, Krela-Kaźmierczak, I
Nutrients. 2020;12(3)
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Nutrition is a major factor influencing obesity associated heart disease risk, however many people with this disease do not follow nutritional recommendations. This review of 155 studies aimed to summarise dietary aspects of heart disease prevention. The paper began by outlining the role of obesity through the development of other disorders that contribute to heart disease, such as type 2 diabetes, high blood pressure and blood sugar imbalance. The quantity and distribution of fat tissue also can contribute to heart disease risk, especially if it is located within the heart or around the major organs of the body. Dietary factors which can increase heart disease risk were described as an increased intake of processed foods, sugar, salt and certain fats and low intakes of fruit, vegetables, fibre, whole grains, beans and nuts. The Mediterranean diet, the dietary approaches to stop hypertension (DASH) diet, plant-based diets, the portfolio dietary pattern and low carbohydrate diets were all reviewed and although mixed results were stated for low carbohydrate diets, most of the diets reviewed reported improved heart disease outcomes. The role of intestinal microbiota in heart disease were also reviewed and the influence of a poor diet was implicated in imbalanced gut microbiota and the development of heart disease. It was concluded that an unhealthy diet can contribute to heart disease and that dietary patterns such as the Mediterranean diet and plant-based diets may be favourable for its management. This study could be used by healthcare professionals to individualise dietary recommendations for patients with heart disease or who are at risk of it.
Abstract
Although cardiovascular disease and its risk factors have been widely studied and new methods of diagnosis and treatment have been developed and implemented, the morbidity and mortality levels are still rising-cardiovascular disease is responsible for more than four million deaths each year in Europe alone. Even though nutrition is classified as one of the main and changeable risk factors, the quality of the diet in the majority of people does not follow the recommendations essential for prevention of obesity and cardiovascular disease. It demonstrates the need for better nutritional education in cardiovascular disease prevention and treatment, and the need to emphasize dietary components most relevant in cardiovascular disease. In our non-systematic review, we summarize the most recent knowledge about nutritional risk and prevention in cardiovascular disease and obesity.
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Menopause-Associated Lipid Metabolic Disorders and Foods Beneficial for Postmenopausal Women.
Ko, SH, Kim, HS
Nutrients. 2020;12(1)
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Menopause is the absence of menstruation due to the loss of ovarian activity with ageing. During this transition period, changes in hormones, primarily the decline in the oestrogen estradiol, give rise to altered lipid metabolism. An unfavourable lipid profile presents a risk for metabolic disorders, such as cardiovascular diseases and type 2 diabetes. Post-menopausal changes also lead to shifts in body fat and fat distribution, resulting in an increased tendency for central fat accumulation and obesity. Obesity is associated with insulin resistance. This susceptibility for weight accumulation is possibly also driven by the age-associated decline in skeletal muscle, which reduces metabolic energy expenditure. This review summarizes the physiology of menopause and postmenopause and the consequential impact on lipid metabolism. In addition, there is a discussion of dietary recommendations, nutritional and plant-derived compounds that could support the management of menopause associated changes in lipid levels, metabolic risk factors and obesity. The recommendations discussed include traditional healthy diets and low-calorie diets, with attention drawn to adequate protein intake. Furthermore, the role of probiotics, nutritional and plant-sourced constituents are considered, including Vitamin D, Omega-3 fatty acids, antioxidants like Vitamin A, β-carotene, Vitamin C and E, genistein, resveratrol, flavonoids, indoles and capsaicin. The authors advocate sourcing these compounds from a varied whole-foods diet, which would minimize nutrient interactions and absorption issues that can occur with supplementation. This review may be of interest to those supporting the nutritional needs of menopausal and post-menopausal women, that are experiencing or are at risk of experiencing metabolic disorders.
Abstract
Menopause is clinically diagnosed as a condition when a woman has not menstruated for one year. During the menopausal transition period, there is an emergence of various lipid metabolic disorders due to hormonal changes, such as decreased levels of estrogens and increased levels of circulating androgens; these may lead to the development of metabolic syndromes including cardiovascular diseases and type 2 diabetes. Dysregulation of lipid metabolism affects the body fat mass, fat-free mass, fatty acid metabolism, and various aspects of energy metabolism, such as basal metabolic ratio, adiposity, and obesity. Moreover, menopause is also associated with alterations in the levels of various lipids circulating in the blood, such as lipoproteins, apolipoproteins, low-density lipoproteins (LDLs), high-density lipoproteins (HDL) and triacylglycerol (TG). Alterations in lipid metabolism and excessive adipose tissue play a key role in the synthesis of excess fatty acids, adipocytokines, proinflammatory cytokines, and reactive oxygen species, which cause lipid peroxidation and result in the development of insulin resistance, abdominal adiposity, and dyslipidemia. This review discusses dietary recommendations and beneficial compounds, such as vitamin D, omega-3 fatty acids, antioxidants, phytochemicals-and their food sources-to aid the management of abnormal lipid metabolism in postmenopausal women.
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Effect of probiotics on lipid profiles and blood pressure in patients with type 2 diabetes: A meta-analysis of RCTs.
He, J, Zhang, F, Han, Y
Medicine. 2017;96(51):e9166
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Plain language summary
Type 2 diabetes mellitus (T2DM) is the most common metabolic disorder worldwide. Though many clinical studies have explored the effects of probiotics on T2DM they have concluded mixed results. The purpose of this meta-analysis was to evaluate all current randomised controlled trials and determine the effect of probiotics on lipid profiles and blood pressure in patients with T2DM. According to the existing literature, probiotic supplementation for patients with T2DM has a positive effect by lowering total cholesterol and increasing high-density lipoproteins (HDLs). While these beneficial effects on lipid profiles and blood pressure have been found, the authors conclude there is still a need for a multi-centre, longitudinal study to better understand the effects of probiotics on patients with T2DM.
Abstract
BACKGROUND This meta-analysis aimed to systematically evaluate the effects of probiotics on blood lipid and blood pressure among patients with type 2 diabetes mellitus (T2DM) based on the randomized controlled studies. METHODS PubMed, Cochrane, Embase, Wanfang, China National Knowledge Infrastructure, and VIP database were searched by the index words to identify the qualified randomized control trial. The latest research was done in the January 2017. Mean difference (MD) along with 95% confidence interval (CI) was used to analyze the included outcomes. RESULTS Ten trials were included at last with 297 patients in the treatment group and 294 patients in the control group. Probiotics significantly decreased the value of total cholesterol (SMD -0.57, 95% CI -0.92 to 0.21), triglyceride (SMD -0.66, 95% CI -0.93 to 0.39), low-density lipoprotein (SMD -0.40, 95% CI -0.79 to 0.01), systolic blood pressure (WMD -5.04, 95% CI -8.8 to 1.20), diastolic blood pressure (SMD -0.39, 95% CI -0.62 to 0.17), fasting blood glucose (FBG) (SMD 3.54, 95% CI 1.94-5.15) compared with the placebo treatment. Apart from this, probiotics could significantly improve the value of high-density lipoprotein (SMD 0.38, 95% CI 0.03-0.73). CONCLUSION Probiotics may decrease the indexes of lipid profile, blood pressure, and FBG in patients with T2DM; application of probiotics might be a new method for lipid profiles and blood pressure management in T2DM.