Dietary fibre for the primary prevention of cardiovascular disease

Relationships between sodium, fats and carbohydrates on blood pressure, cholesterol and HbA1c: an umbrella review of systematic reviews

Background

The relationship between nutrition and health is complex and the evidence to describe it broad and diffuse. This review brings together evidence for the effect of nutrients on cardiometabolic risk factors.

Methods

An umbrella review identified systematic reviews of randomised controlled trials and meta-analyses estimating the effects of fats, carbohydrates and sodium on blood pressure, cholesterol and haemoglobin A1c (HbA1c). Medline, Embase, Cochrane Library and Science Citation Index were search through 26 May 2020, with supplementary searches of grey literature and websites. English language systematic reviews and meta-analyses were included that assessed the effect of sodium, carbohydrates or fat on blood pressure, cholesterol and HbA1c. Reviews were purposively selected using a sampling framework matrix. The quality of evidence was assessed with A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR2) checklist, evidence synthesised in a narrative review and causal pathways diagram.

Results

Forty-three systematic reviews were included. Blood pressure was significantly associated with sodium, fibre and fat. Sodium, fats and carbohydrates were significantly associated with cholesterol. Monounsaturated fat, fibre and sugars were associated with HbA1c.

Conclusion

Multiple relationships between nutrients and cardiometabolic risk factors were identified and summarised in an accessible way for public health researchers. The review identifies associations, inconsistencies and gaps in evidence linking nutrition to cardiometabolic health.

Diet and Lipid-Lowering Nutraceuticals in Pediatric Patients with Familial Hypercholesterolemia

Familial hypercholesterolemia is a genetically determined disease characterized by elevated plasma total and LDL cholesterol levels from the very first years of life, leading to early atherosclerosis. Nutritional intervention is the first-line treatment, complemented with nutraceuticals and drug therapy when necessary. Nutraceuticals with a lipid-lowering effect have been extensively studied in the past few decades, and have been recently included in international guidelines as a complement to nutritional and pharmacological treatment in subjects with dyslipidemia. In this review, we explore current nutritional interventions for dyslipidemia in childhood, with a specific focus on the main nutraceuticals studied for treating severe dyslipidemia in pediatric patients. Additionally, we briefly describe their primary mechanisms of action and highlight the advantages and risks associated with the use of lipid-lowering nutraceuticals in childhood.

Association between dietary vitamin C and abdominal aortic calcification among the US adults

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of mortality, and vascular calcification has been highly correlated with CVD events. Abdominal aortic calcification (AAC) has been shown to predict subclinical CVD and incident CVD events. However, the relationship between vitamin C and abdominal aortic calcification remains unclear.

OBJECTIVE

To investigate the relationship of dietary vitamin C with AAC among the adult population in the US.

METHODS

The National Health and Nutrition Examination Survey (NHANES) 2013-2014 provided the data for the cross-sectional study. 2297 subjects (1089 males) were included in the study. Two scoring systems, AAC 24-point scale (Kauppila) and AAC 8-point scale (Schousboe), were used for the measurement of AAC score. Dietary vitamin C intake was calculated as the average of two rounds of 24-h interview recall data and classified in tertiles for analysis. We applied weighted multiple regression analyses to assess the relationship of dietary vitamin C with AAC score and the risk of having AAC. To ensure the robustness of the findings, subgroup and sensitivity analyses were performed. Additionally, smooth curve fittings, using generalized additive models (GAM) were employed to visualize potential nonlinear relationships. Furthermore, an exploratory analysis on the relationship of vitamin C supplements with AAC was also conducted.

RESULTS

The results showed that higher dietary vitamin C intake was related to a reduction in AAC score (AAC-24: β = -0.338, 95% confidence interval [CI] -0.565, -0.111, P = 0.004; AAC-8: β = -0.132, 95%CI -0.217, -0.047, P = 0.002), and lower risk of AAC (odds ratio [OR] = 0.807, 95%CI 0.659, 0.989, P = 0.038). However, the relationship of vitamin C supplements with AAC was not identified.

CONCLUSIONS

The study revealed that higher intake of dietary vitamin C rather than vitamin C supplements was related to reduced AAC score and lower risk of AAC, indicating that diets rich in vitamin C are recommended due to its potential benefits for protecting against vascular calcification and CVD among the adult population in the US.

Effect of soluble fiber on blood pressure in adults: a systematic review and dose-response meta-analysis of randomized controlled trials

OBJECTIVES

Pervious epidemiologic evidence indicates that soluble fiber is protective against hypertention: however, randomized controlled trials (RCTs) have presented varying results. In the present study, we aimed to conduct a systematic review and dose-response meta-analysis to summarize published RCTs which assess the effect of soluble fiber supplementation on systolic blood pressure (SBP) and diastolic blood pressure (DBP).

METHODS

Scopus, PubMed, and ISI Web of Sciences were searched to identify relevant studies up to Aug 2022. We estimated the change in blood pressure for each 5 g/d increment in soluble fiber supplementation in each trial and then calculated the weighted mean difference (WMD) 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 for study was assessed using the Cochrane tool. Publication bias was evaluated via funnel plot and Begg's test and Egger's test.

RESULTS

Eighty-three eligible studies with total sample size of 5,985 participants were included in the meta-analysis. Soluble fiber supplementation significantly decreased SBP (WMD: -1.36 mmHg, 95% CI: -2.13 to -0.60, P < 0.001; I2 = 47.1%, P < 0.001) and DBP (WMD: -0.72 mmHg, 95% CI: -1.26 to -0.18, P = 0.009; I2 = 45.4%, P < 0.001). Each 5 g/d increment in soluble fiber supplementation had a significant reduction in SBP (WMD: -0.54 mmHg; 95%CI: -0.86, -0.22, P = 0.001; I2 = 52.2, Phet < 0.001) and DBP (WMD: -0.28 mmHg; 95%CI: -0.49, -0.80, P = 0.007; I2 = 43.1%, Phet < 0.001). The levels of SBP decreased proportionally with the increase in soluble fiber supplementation up to 20 g/d (MD20g/d: -1.79 mmHg, 95%CI: -2.86, -0.71).

CONCLUSION

Current evidence indicated the beneficial effect of soluble fiber supplementation on blood pressure. Our findings suggest that soluble fiber supplementation could contribute to the management of hypertension and the reduction of cardiovascular disease risk.

The Relationship Between Dietary Fiber Intake and Blood Pressure Worldwide: A Systematic Review

Cardiovascular diseases (CVDs) are a significant global health concern, necessitating effective preventive measures. Dietary fiber has gained attention as a potential cardiovascular risk factor modifier. Although its effects on various CVD risk markers such as cholesterol levels and blood glucose levels have been explored, the relationship between dietary fiber and blood pressure remains somewhat elusive across the different studies conducted worldwide. In this systematic review, we conducted an extensive analysis of recent research from a global perspective, aiming to elucidate the relationship between dietary fiber intake and blood pressure. From an initial pool of more than 24,500 articles retrieved from PubMed and Google Scholar, we rigorously selected 11 studies published in the last decade (post-2013) to ensure up-to-date insights. These selected studies encompass diverse populations from different regions worldwide, allowing for a comprehensive global assessment. Our analysis revealed a positive overall impact of increased dietary fiber intake on blood pressure levels. Despite variations in study parameters, consistent trends were observed across multiple continents. This systematic review underscores the potential of dietary fiber intake to reduce blood pressure and improve cardiovascular health globally. This review serves as a global analysis and updates on the developments about the potential association between dietary fiber and blood pressure levels. While the findings are promising, further research is essential to elucidate underlying mechanisms and ensure global consistency. Collaborative efforts and ongoing investigation are crucial for harnessing the cardiovascular benefits of dietary fiber and addressing the worldwide burden of hypertension.

Do markers of adiposity and glycaemia mediate the association between low carbohydrate diet and cardiovascular risk factors: findings from the UK National Diet and Nutrition Survey (NDNS) 2008-2016

Objectives

To examine the associations between low carbohydrate diet (LCD) and conventional cardiovascular risk factors and investigate whether these associations are mediated by body mass index (BMI), waist circumference (WC) and haemoglobin A1c (HbA1c) applying causal mediation analyses.

Methods

We included 3640 adults aged 45-80 years from the UK National Diet and Nutrition Survey programme (2008-2016) with data on dietary intake, anthropometric and biochemical parameters. Four hypothetical interventions were examined: (1) LCD, (2) Low carbohydrate (LC) and high fibre diet (LCHF), (3) LC and high saturated fat diet (LCHS) and (4) LC and high unsaturated fat diet (LCHU). BMI and WC were used as markers of obesity. Biochemical markers included HbA1c, total cholesterol, high-density lipoprotein and low-density lipoprotein (LDL) cholesterol, triglycerides, systolic and diastolic blood pressure and C reactive protein (CRP). BMI, WC and HbA1c were used as a mediator of the effects. The analysis was adjusted for sociodemographic characteristic, smoking, estimated total energy intake, alcohol consumption and antihypertensive medication. To identify a potential causal effect of LCD on cardiovascular disease (CVD) risk, we estimated the average treatment effect, and corresponding p values and CI for the total, indirect and direct effect of the treatment on the outcome.

Results

BMI, WC and HbA1c fully mediated the association between LCD and triglycerides and fully mediated the effects of LCHF on LDL, although BMI and WC were not sufficient to fully mediate the effects of LCHF on triglycerides and CRP. BMI alone fully mediated the effects of LCHS on HbA1c, triglycerides, LDL and CRP. None of these mediators explained the effect of LCHU on CVD risk markers.

Conclusion

The causal hypotheses tested in this study demonstrate that individuals on LCD with high fibre intakes improved their CVD markers as expected, but those on LCD who increase fat intake had no effects on CVD markers mediated by obesity and diabetes.

Low glycaemic index or low glycaemic load diets for people with overweight or obesity

BACKGROUND

The prevalence of obesity is increasing worldwide, yet nutritional management remains contentious. It has been suggested that low glycaemic index (GI) or low glycaemic load (GL) diets may stimulate greater weight loss than higher GI/GL diets or other weight reduction diets. The previous version of this review, published in 2007, found mainly short-term intervention studies. Since then, randomised controlled trials (RCTs) with longer-term follow-up have become available, warranting an update of this review.

OBJECTIVES

To assess the effects of low glycaemic index or low glycaemic load diets on weight loss in people with overweight or obesity.

SEARCH METHODS

We searched CENTRAL, MEDLINE, one other database, and two clinical trials registers from their inception to 25 May 2022. We did not apply any language restrictions.

SELECTION CRITERIA

We included RCTs with a minimum duration of eight weeks comparing low GI/GL diets to higher GI/GL diets or any other diets in people with overweight or obesity.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We conducted two main comparisons: low GI/GL diets versus higher GI/GL diets and low GI/GL diets versus any other diet. Our main outcomes included change in body weight and body mass index, adverse events, health-related quality of life, and mortality. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

In this updated review, we included 10 studies (1210 participants); nine were newly-identified studies. We included only one study from the previous version of this review, following a revision of inclusion criteria. We listed five studies as 'awaiting classification' and one study as 'ongoing'. Of the 10 included studies, seven compared low GI/GL diets (233 participants) with higher GI/GL diets (222 participants) and three studies compared low GI/GL diets (379 participants) with any other diet (376 participants). One study included children (50 participants); one study included adults aged over 65 years (24 participants); the remaining studies included adults (1136 participants). The duration of the interventions varied from eight weeks to 18 months. All trials had an unclear or high risk of bias across several domains.  Low GI/GL diets versus higher GI/GL diets Low GI/GL diets probably result in little to no difference in change in body weight compared to higher GI/GL diets (mean difference (MD) -0.82 kg, 95% confidence interval (CI) -1.92 to 0.28; I2 = 52%; 7 studies, 403 participants; moderate-certainty evidence). Evidence from four studies reporting change in body mass index (BMI) indicated low GI/GL diets may result in little to no difference in change in BMI compared to higher GI/GL diets (MD -0.45 kg/m2, 95% CI -1.02 to 0.12; I2 = 22%; 186 participants; low-certainty evidence)at the end of the study periods. One study assessing participants' mood indicated that low GI/GL diets may improve mood compared to higher GI/GL diets, but the evidence is very uncertain (MD -3.5, 95% CI -9.33 to 2.33; 42 participants; very low-certainty evidence). Two studies assessing adverse events did not report any adverse events; we judged this outcome to have very low-certainty evidence. No studies reported on all-cause mortality.    For the secondary outcomes, low GI/GL diets may result in little to no difference in fat mass compared to higher GI/GL diets (MD -0.86 kg, 95% CI -1.52 to -0.20; I2 = 6%; 6 studies, 295 participants; low certainty-evidence). Similarly, low GI/GL diets may result in little to no difference in fasting blood glucose level compared to higher GI/GL diets (MD 0.12 mmol/L, 95% CI 0.03 to 0.21; I2 = 0%; 6 studies, 344 participants; low-certainty evidence).  Low GI/GL diets versus any other diet Low GI/GL diets probably result in little to no difference in change in body weight compared to other diets (MD -1.24 kg, 95% CI -2.82 to 0.34; I2 = 70%; 3 studies, 723 participants; moderate-certainty evidence). The evidence suggests that low GI/GL diets probably result in little to no difference in change in BMI compared to other diets (MD -0.30 kg in favour of low GI/GL diets, 95% CI -0.59 to -0.01; I2 = 0%; 2 studies, 650 participants; moderate-certainty evidence). Two adverse events were reported in one study: one was not related to the intervention, and the other, an eating disorder, may have been related to the intervention. Another study reported 11 adverse events, including hypoglycaemia following an oral glucose tolerance test. The same study reported seven serious adverse events, including kidney stones and diverticulitis. We judged this outcome to have low-certainty evidence. No studies reported on health-related quality of life or all-cause mortality. For the secondary outcomes, none of the studies reported on fat mass. Low GI/GL diets probably do not reduce fasting blood glucose level compared to other diets (MD 0.03 mmol/L, 95% CI -0.05 to 0.12; I2 = 0%; 3 studies, 732 participants; moderate-certainty evidence).  AUTHORS' CONCLUSIONS: The current evidence indicates there may be little to no difference for all main outcomes between low GI/GL diets versus higher GI/GL diets or any other diet. There is insufficient information to draw firm conclusions about the effect of low GI/GL diets on people with overweight or obesity. Most studies had a small sample size, with only a few participants in each comparison group. We rated the certainty of the evidence as moderate to very low. More well-designed and adequately-powered studies are needed. They should follow a standardised intervention protocol, adopt objective outcome measurement since blinding may be difficult to achieve, and make efforts to minimise loss to follow-up. Furthermore, studies in people from a wide range of ethnicities and with a wide range of dietary habits, as well as studies in low- and middle-income countries, are needed.

Targeting intestinal microecology: potential intervention strategies of traditional Chinese medicine for managing hypertension

Hypertension has become one of the major public health problems in the world. At present, the pathogenesis of hypertension has still not been completely elucidated. In recent years, an increasing evidence shows that intestinal microecology is closely related to hypertension, which provides a new thinking for the prevention and treatment of hypertension. Traditional Chinese medicine (TCM) has unique advantages in the treatment of hypertension. Taking intestinal microecology as the target, it is possible to interpreting the scientific connotation of TCM prevention and treatment of hypertension by updating the treatment concept of hypertension, so as to improve the therapeutic effect. In our study, the clinical evidence for TCM treatment of hypertension was systematicly summarized. And the relationship among TCM, intestinal microecology and hypertension was analyzed. In addition, the methods by which TCM regulates intestinal microecology to prevent and treat hypertension were presented, to provide new research ideas for prevention and treatment of hypertension.

The effects of vegetarian diets on glycemia and lipid parameters in adult patients with overweight and obesity: a systematic review and meta-analysis

Several randomized controlled trials have reported the effects of vegetarian diets on blood lipids and glucose homeostasis in adults, but not in overweight or obese individuals. Thus, the purpose of this study was to evaluate the effects of vegetarian diets on blood lipids and glucose homeostasis in overweight or obese adults by systematic review and meta-analysis. We searched Medline, Embase, and the Cochrane Library through October 2021. We chose to include overweight or obese patients in the studies of the vegetarian diet for metabolic control. Seven trials with a total of 783 overweight or obese adult were included in the meta-analysis. The analysis of the data revealed that the vegetarian diets significantly reduced low-density lipoprotein cholesterol (LDL-C) (WMD, -0.31; 95% CI, -0.46 to -0.16), total cholesterol (TC) (WMD, -0.37; 95% CI, -0.52 to -0.22), and HbA1c (WMD (%), -0.33; 95% CI, -0.55 to -0.11). The vegetarian diets had an elevated effect on blood triglycerides (WMD, 0.29; 95% CI, 0.11-0.47). However, there were no significant effects of vegetarian diets on high-density lipoprotein cholesterol (HDLC), Fasting plasma glucose(FPG), and HOMA-IR in these individuals. The results of this study suggest that vegetarian diets effectively reduce LDL-C, TC, and HbA1c levels, thus functioning as a promising therapeutic strategy for improving the metabolic dysfunction in overweight or obese individuals. However, further large-scale clinical trials are required to confirm the validity of these findings.

Association between healthy eating index-2015 and abdominal aortic calcification among US Adults

Aims

To evaluate the relationship of the healthy eating index-2015 (HEI-2015) with abdominal aortic calcification (AAC) in US adults.

Methods

We conducted a cross-sectional study with data extracted from the National Health and Nutrition Examination Survey (NHANES). AAC score was measured using the scoring system of Kauppila (AAC-24) and Schousboe (AAC-8). HEI-2015, which was used for evaluating compliance with Dietary Guidelines for Americans (DGA), was calculated through two rounds of 24-h recall interviews. HEI-2015 was categorized as inadequate (<50), average (50~70), and optimal (≥70) groups for analysis, while the AAC-24 score was grouped by whether the score was >0. Weighted multiple regression analyses were conducted to estimate the association of HEI-2015 with AAC score and the presence of AAC. Moreover, smooth curve fittings, based on a generalized additive model (GAM), were applied to evaluate a possible non-linear relationship. Sensitivity analysis and subgroup analysis were performed to provide more supporting information.

Results

A total of 2,704 participants were included in the study (mean age, 57.61 ± 11.40 years; 51.78% were women). The mean score of HEI-2015 was 56.09 ± 13.40 (41.33 ± 6.28, 59.44 ± 5.54, and 76.90 ± 5.37 for inadequate, average, and optimal groups, respectively). After adjusting for covariates, higher HEI-2015 was associated with decreased AAC score (AAC-24: β = -0.121, 95% CI: -0.214, -0.028, P = 0.010; AAC-8: β= -0.054, 95% CI: -0.088, -0.019, P = 0.003) and lower risk of AAC (OR = 0.921, 95% CI: 0.855, 0.993, P = 0.031). Among the components of HEI-2015, a higher intake of fruits, greens, and beans was associated with a lower AAC score. Subgroup analysis showed that an inverse association of HEI-2015 with AAC score existed among different groups.

Conclusion

The study presented that higher HEI-2015 was related to a lower AAC score and decreased risk of having AAC, indicating that greater compliance with 2015-2020 DGA, assessed by HEI-2015, might be beneficial for preventing vascular calcification and CVD among US adults.

Investigating the Regulatory Process, Safety, Efficacy and Product Transparency for Nutraceuticals in the USA, Europe and Australia

Increased numbers of patients with chronic conditions use nutraceuticals or food-based therapeutics. However, to date, there is no global consensus on the regulatory processes for nutraceuticals. With the increased use, issues of quality and safety have also arisen. This review summarises the current regulations held for nutraceuticals in the USA, European and Australian jurisdictions using regulatory authority sites and databases. The efficacy and safety concerns, product development, gaps in regulation and challenges in ensuring product authenticity are also summarised. The data highlight the complexity that the globalisation of nutraceuticals brings with respect to challenges in regulation and associated claims regarding efficacy and safety. The development of an effective system with integrity is needed to increase vertical collaboration between consumers, healthcare practitioners, and government agencies and the development of international risk assessment criteria and botanical compendia. This will help in greater transparency and improved trust in the process and products. Emerging technologies could play a role in improving systems engineering by information sharing and leveraging the strengths of different countries. In conclusion, nutraceuticals have been poorly regulated leading to spurious claims based on little or no real evidence. This makes it difficult to separate meaningful results from poor data. More stringent regulation and an effective system of integrity are required to ensure efficacy and safety and enable the adequate monitoring and increase consumer and healthcare professionals' confidence.

Determining optimal strategies for primary prevention of cardiovascular disease: systematic review of cost-effectiveness analyses in the United Kingdom

BACKGROUND

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide. The aim of the study was to guide researchers and commissioners of cardiovascular disease preventative services towards possible cost-effective interventions by reviewing published economic analyses of interventions for the primary prevention of cardiovascular disease, conducted for or within the UK NHS.

METHODS

In January 2021, electronic searches of MEDLINE and Embase were carried out to find economic evaluations of cardiovascular disease preventative services. We included fully published economic evaluations (including economic models) conducted alongside randomised controlled trials of any form of intervention that was aimed at the primary prevention of cardiovascular disease, including, but not limited to, drugs, diet, physical activity and public health. Full systematic review methods were used with predetermined inclusion/exclusion criteria, data extraction and formal quality appraisal [using the Consolidated Health Economic Evaluation Reporting Standards checklist and the framework for the quality assessment of decision analytic modelling by Philips et al. (Philips Z, Ginnelly L, Sculpher M, Claxton K, Golder S, Riemsma R, et al. Review of guidelines for good practice in decision-analytic modelling in health technology assessment. Health Technol Assess 2004;8(36)].

RESULTS

Of 4351 non-duplicate citations, eight articles met the review's inclusion criteria. The eight articles focused on health promotion (n = 3), lipid-lowering medicine (n = 4) and blood pressure-lowering medication (n = 1). The majority of the populations in each study had at least one risk factor for cardiovascular disease or were at high risk of cardiovascular disease. For the primary prevention of cardiovascular disease, all strategies were cost-effective at a threshold of £25,000 per quality-adjusted life-year, except increasing motivational interviewing in addition to other behaviour change strategies. Where the cost per quality-adjusted life-year gained was reported, interventions varied from dominant (i.e. less expensive and more effective than the comparator intervention) to £55,000 per quality-adjusted life-year gained.

FUTURE WORK AND LIMITATIONS

We found few health economic analyses of interventions for primary cardiovascular disease prevention conducted within the last decade. Future economic assessments should be undertaken and presented in accordance with best practices so that future reviews may make clear recommendations to improve health policy.

CONCLUSIONS

It is difficult to establish direct comparisons or draw firm conclusions because of the uncertainty and heterogeneity among studies. However, interventions conducted for or within the UK NHS were likely to be cost-effective in people at increased risk of cardiovascular disease when compared with usual care or no intervention.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in Health Technology Assessment. See the NIHR Journals Library website for further project information.

Narrative Review on the Effects of Oat and Sprouted Oat Components on Blood Pressure

Hypertension (HTN) is a major risk factor for cardiovascular disease (CVD) and cognitive decline. Elevations in blood pressure (BP) leading to HTN can be found in young adults with increased prevalence as people age. Oats are known to decrease CVD risk via an established effect of β-glucan on the attenuation of blood cholesterol. Many past studies on CVD and oats have also reported a decrease in BP; however, a thorough assessment of oats and BP has not been conducted. Moreover, oats deliver several beneficial dietary components with putative beneficial effects on BP or endothelial function, such as β-glucan, γ-amino butyric acid (GABA), and phytochemicals such as avenanthramides. We conducted a comprehensive search for systematic reviews, meta-analyses, and clinical intervention studies on oats and BP and identified 18 randomized controlled trials (RCTs) and three meta-analyses that supported the role of oats in decreasing BP. Emerging data also suggest oat consumption may reduce the use of anti-hypertensive medications. The majority of these studies utilized whole oats or oat bran, which include a vast array of oat bioactives. Therefore, we also extensively reviewed the literature on these bioactives and their putative effect on BP-relevant mechanisms. The data suggest several oat components, such as GABA, as well as the delivery of high-quality plant protein and fermentable prebiotic fiber, may contribute to the anti-HTN effect of oats. In particular, GABA is enhanced in oat sprouts, which suggests this food may be particularly beneficial for healthy BP management.

Empirical evidence of study design biases in nutrition randomised controlled trials: a meta-epidemiological study

BACKGROUND

Instruments to critically appraise randomised controlled trials (RCTs) are based on evidence from meta-epidemiological studies. We aim to conduct a meta-epidemiological study on the average bias associated with reported methodological trial characteristics such as random sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and compliance of RCTs in nutrition research.

METHODS

We searched the Cochrane Database of Systematic Reviews, for systematic reviews of RCTs, published between 01 January 2010 and 31 December 2019. We combined the estimates of the average bias (e.g. ratio of risk ratios [RRR] or differences in standardised mean differences) in meta-analyses using the random-effects model. Subgroup analyses were conducted to investigate the potential differences among the RCTs with low versus high/unclear risk of bias with respect to the different types of interventions (e.g. micronutrients, fatty acids, dietary approach), outcomes (e.g. mortality, pregnancy outcomes), and type of outcome (objective, subjective). Heterogeneity was assessed through I² and τ², and prediction intervals were calculated.

RESULTS

We included 27 Cochrane nutrition reviews with 77 meta-analyses (n = 927 RCTs). The available evidence suggests that intervention effect estimates may not be exaggerated in RCTs with high/unclear risk of bias (versus low) judgement for sequence generation (RRR 0.97, 95% CI 0.93 to 1.02; I² = 28%; τ² = 0.002), allocation concealment (RRR 1.00, 95% CI 0.96 to 1.04; I² = 27%; τ² = 0.001), blinding of participants and personnel (RRR 0.95, 95% CI 0.91 to 1.00; I² = 23%; τ² = 0), selective reporting (RRR 0.97, 95% CI 0.92 to 1.02; I² = 24%; τ² = 0), and compliance (RRR 0.95, 95% CI 0.89 to 1.02; I² = 0%; τ² = 0). Intervention effect estimates seemed to be exaggerated in RCTs with a high/unclear risk of bias judgement for blinding of outcome assessment (RRR 0.81, 95% CI 0.70 to 0.94; I² = 26%; τ² = 0.03), which was predominately driven by subjective outcomes, and incomplete outcome data (RRR 0.92, 95% CI 0.88 to 0.97; I² = 22%; τ² = 0.001). For continuous outcomes, no differences were observed, except for selective reporting.

CONCLUSIONS

On average, most characteristics of nutrition RCTs may not exaggerate intervention effect estimates, but the average bias appears to be greatest in trials of subjective outcomes. Replication of this study is suggested in this field to keep this conclusion updated.

Dietary Risk Factors and Eating Behaviors in Peripheral Arterial Disease (PAD)

Dietary risk factors play a fundamental role in the prevention and progression of atherosclerosis and PAD (Peripheral Arterial Disease). The impact of nutrition, however, defined as the process of taking in food and using it for growth, metabolism and repair, remains undefined with regard to PAD. This article describes the interplay between nutrition and the development/progression of PAD. We reviewed 688 articles, including key articles, narrative and systematic reviews, meta-analyses and clinical studies. We analyzed the interaction between nutrition and PAD predictors, and subsequently created four descriptive tables to summarize the relationship between PAD, dietary risk factors and outcomes. We comprehensively reviewed the role of well-studied diets (Mediterranean, vegetarian/vegan, low-carbohydrate ketogenic and intermittent fasting diet) and prevalent eating behaviors (emotional and binge eating, night eating and sleeping disorders, anorexia, bulimia, skipping meals, home cooking and fast/ultra-processed food consumption) on the traditional risk factors of PAD. Moreover, we analyzed the interplay between PAD and nutritional status, nutrients, dietary patterns and eating habits. Dietary patterns and eating disorders affect the development and progression of PAD, as well as its disabling complications including major adverse cardiovascular events (MACE) and major adverse limb events (MALE). Nutrition and dietary risk factor modification are important targets to reduce the risk of PAD as well as the subsequent development of MACE and MALE.

Global research trends in atherosclerosis: A bibliometric and visualized study

Background

Increasing evidence has spurred a considerable evolution of concepts related to atherosclerosis, prompting the need to provide a comprehensive view of the growing literature. By retrieving publications in the Web of Science Core Collection (WoSCC) of Clarivate Analytics, we conducted a bibliometric analysis of the scientific literature on atherosclerosis to describe the research landscape.

Methods

A search was conducted of the WoSCC for articles and reviews serving exclusively as a source of information on atherosclerosis published between 2012 and 2022. Microsoft Excel 2019 was used to chart the annual productivity of research relevant to atherosclerosis. Through CiteSpace and VOSviewer, the most prolific countries or regions, authors, journals, and resource-, intellectual-, and knowledge-sharing in atherosclerosis research, as well as co-citation analysis of references and keywords, were analyzed.

Results

A total of 20,014 publications were retrieved. In terms of publications, the United States remains the most productive country (6,390, 31,93%). The most publications have been contributed by Johns Hopkins Univ (730, 3.65%). ALVARO ALONSO produced the most published works (171, 0.85%). With a betweenness centrality of 0.17, ERIN D MICHOS was the most influential author. The most prolific journal was identified as Atherosclerosis (893, 4.46%). Circulation received the most co-citations (14,939, 2.79%). Keywords with the ongoing strong citation bursts were “nucleotide-binding oligomerization (NOD), Leucine-rich repeat (LRR)-containing protein (NLRP3) inflammasome,” “short-chain fatty acids (SCFAs),” “exosome,” and “homeostasis,” etc.

Conclusion

The research on atherosclerosis is driven mostly by North America and Europe. Intensive research has focused on the link between inflammation and atherosclerosis, as well as its complications. Specifically, the NLRP3 inflammasome, interleukin-1β, gut microbiota and SCFAs, exosome, long non-coding RNAs, autophagy, and cellular senescence were described to be hot issues in the field.

A New Health Promotion Program That Includes Wadaiko Rhythm Exercise to Maintain the Health of Persons Excluded from Receiving Specific Health Guidance

This study examined the effectiveness of a new health promotion program, which is a collective intervention program aimed at improving lifestyle habits. It was designed as a one-year prospective cohort study. This program targeted non-obese persons at risk of developing lifestyle-related diseases and participants with hypertension, dyslipidemia, or hyperglycemia who were not included in the specific health guidance system in Japan. The Wadaiko rhythm exercise, which is a traditional performing art, is incorporated into this intervention as an enjoyable routine that can help participants continue the program, preventing them from dropping out. After a one-year follow-up, the effectiveness of the health promotion program was evaluated in 18 participants (2 males, 16 females; mean age 65.2 ± 3.4 years) and 92 controls. The results showed that triglyceride in the intervention group significantly decreased (−24.5 mg/dL; p = 0.02; 95% confidence interval [CI], −44.73 to −4.27) and high-density lipoprotein cholesterol significantly increased (+6.1 mg/dL; p < 0.01; 95% CI, 2.46 to 9.65), although levels in the control group did not change. These results suggest that the health promotion program could contribute to lifestyle habit improvements in those who are excluded from receiving specific health guidance.

The Effect of Rye-Based Foods on Postprandial Plasma Insulin Concentration: The Rye Factor

Consumption of whole grain has been associated with lower incidence of type-2 diabetes, cardiovascular disease and their risk factors including improved glycemic control. In comparison with other whole grain products, rye bread has been shown to induce lower insulin response in the postprandial phase, without affecting the glucose response. This phenomenon has been referred to as the “rye factor” and is being explored in this review where we summarize the findings from meal and extended meal studies including rye-based foods. Overall, results from intervention studies showed that rye-based foods vs. (wheat) control foods had positive effect on both insulin and glucose responses in the postprandial phase, rather than on insulin alone. Mechanistic studies have shown that the rye factor phenomenon might be due to slowing of the glucose uptake in the intestine. However, this has also been shown for wheat-based bread and is likely an effect of structural properties of the investigated foods rather than the rye per se. More carefully controlled studies where standardized structural properties of different cereals are linked to the postprandial response are needed to further elucidate the underlying mechanisms and determinants for the effect of specific cereals and product traits on postprandial glycemic control.

[Long known and mostly unused: lifestyle measures to support lipid-lowering therapy]

Dyslipidemias are common metabolic disorders in Western industrialized countries. Lifestyle measures such as increasing physical activity and improving diet were for many years the only measure for their treatment. Because of their health-promoting effects, guidelines for the treatment of dyslipidemias consider lifestyle measures to be the basis of any drug therapy. Due to the numerous efficient options for intensive lipid-lowering medication, lifestyle measures are recommended by responsible physicians, but their implementation is usually not intensively pursued due to the large time commitment; in contrast to sustained recommendations for increasing physical activity and normalizing body weight, nutritional therapists are too rarely consulted as specialists despite the significant effects our diet has on cardiovascular risk factors such as LDL-cholesterol, triglycerides and blood pressure. In this review, the principles of nutritional therapy of dyslipidemias are described, and it is outlined how recent studies support the plausibility and evidence of the individual measures.

Current Research on the Effects of Non-Digestible Carbohydrates on Metabolic Disease

Metabolic diseases (MDs), including cardiovascular diseases (CVDs) and diabetes, occur when the body’s normal metabolic processes are disrupted. Behavioral risk factors such as obesity, physical inactivity, and dietary habits are strongly associated with a higher risk of MD. However, scientific evidence strongly suggests that balanced, healthy diets containing non-digestible carbohydrates (NDCs), such as dietary fiber and resistant starch, can reduce the risk of developing MD. In particular, major properties of NDCs, such as water retention, fecal bulking, viscosity, and fermentation in the gut, have been found to be important for reducing the risk of MD by decreasing blood glucose and lipid levels, increasing satiety and insulin sensitivity, and modifying the gut microbiome. Short chain fatty acids produced during the fermentation of NDCs in the gut are mainly responsible for improvement in MD. However, the effects of NDCs are dependent on the type, source, dose, and duration of NDC intake, and some of the mechanisms underlying the efficacy of NDCs on MD remain unclear. In this review, we briefly summarize current studies on the effects of NDCs on MD and discuss potential mechanisms that might contribute to further understanding these effects.

Nutraceuticals for Dyslipidaemia and Glucometabolic Diseases: What the Guidelines Tell Us (and Do Not Tell, Yet)

BACKGROUND

The use of nutraceutical products and functional foods in the cardiovascular and metabolic field is rising in several countries. Preparation and implementation of guidelines are pivotal for translating research-derived knowledge and evidence-based medicine to the clinical practice. Based on these considerations, the aim of this paper is to explore if and how nutraceutical products are discussed by the most recent international guidelines related to cardio-metabolic diseases (dyslipidaemia, obesity, type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) prevention). Some, but not all, guidelines for dyslipidaemia mention nutraceutical products as potential useful options for the treatment of mild dyslipidaemia, but also indicate the low level of evidence associated to their effects on hard endpoints (myocardial infarction, stroke, CVD-related death). In the most recent guidelines on obesity, it is mentioned that no safe and effective dietary supplement nor nutraceutical product is available for the management of weight loss in this condition, and more high-quality studies are necessary in this field. The examined guidelines for T2DM do not mention any specific nutraceutical approach to this disease, nor to milder forms, such as insulin resistance and pre-diabetes.

CONCLUSIONS

The focus on nutraceutical products in the main international guidelines for cardio-metabolic disease management remains limited. Since robust scientific evidence is the background of useful and effective guidelines, the implementation of high-quality clinical research is strongly needed in the field of nutraceutical products for cardio-metabolic diseases.

Colonic Microbiota Profile Characterization of the Responsiveness to Dietary Fibre Treatment in Hypercholesterolemia

This study aimed to determine how the microbiota profile might be predisposed to a better response in blood lipid profiles due to dietary fibre supplementation. A three-arm intervention study that included three different fibre types (mainly insoluble, soluble, and antioxidant fibre) supplemented (19.2 g/day) during 2 months in individuals with hypercholesterolemia was developed. Changes in faecal microbiota and blood lipid profile after fibre supplementation were determined. In all volunteers, regardless of fibre type, an increase in the abundance of Bifidobacterium was observed, and similarly, an inverse relationship between faecal propionic acid and blood LDL-cholesterol, LDL particle size, and LDL/HDL particle ratio (p-values 0.0067, 0.0002, and 0.0067, respectively) was observed. However, not all volunteers presented an improvement in lipid profile. The non-responders to fibre treatment showed a decrease in microbiota diversity (Shannon and Simpson diversity index p-values of 0.0110 and 0.0255, respectively) after the intervention; where the reduction in short-chain fatty acids (SCFAs) producing bacterial genera such as Clostridium XIVa and Ruminococcus after dietary fibre treatment was the main difference. It was concluded that the non-responsiveness to dietary fibre treatment might be mediated by the lack of ability to maintain a stable SCFA producing bacteria diversity and composition after extra fibre intake.

High versus low-added sugar consumption for the primary prevention of cardiovascular disease

BACKGROUND

High intake of added sugar have been suggested to impact the risk for cardiovascular disease (CVD). Knowledge on the subject can contribute to preventing CVD.

OBJECTIVES

To assess the effects of a high versus low-added sugar consumption for primary prevention of CVD in the general population.

SEARCH METHODS

We searched Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, Conference Proceedings Citation Index-Science (CPCI-S) on 2 July 2021. We also conducted a search of ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) Search Portal for ongoing or unpublished trials. The search was performed together with reference checking, citation searching and contact with study authors to identify additional studies. We imposed no restriction on language of publication or publication status.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), including cross-over trials, that compared different levels of added sugar intake. Exclusion criteria were: participants aged below 18 years; diabetes mellitus (type 1 and 2); and previous CVD. Primary outcomes were incident cardiovascular events (coronary, carotid, cerebral and peripheral arterial disease) and all-cause mortality. Secondary outcomes were changes in systolic and diastolic blood pressure, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, fasting plasma glucose and adverse events (gastrointestinal symptoms and impaired dental health).

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 21 RCTs (1110 participants completing the interventions) examining the effects of different levels of added sugar intake with a mean duration of 14 weeks. The study participants were generally described as healthy and the mean age ranged from 22 to 57 years. No studies reported on cardiovascular events or all-cause mortality. There was minimal effect of low intake of added sugar on total cholesterol levels (MD 0.11, 95% CI 0.01 to 0.21; I² = 0%; 16 studies; 763 participants; low certainty of evidence) and triglycerides (MD 0.10, 95% CI 0.03 to 0.17; I² = 3%; 14 studies; 725 participants) but no evidence of effect on LDL-cholesterol and HDL-cholesterol. There was minimal effect on diastolic blood pressure (MD 1.52, 95% CI 0.67 to 2.37; I² = 0%; 13 studies; 873 participants) and on systolic blood pressure (MD 1.44, 95% 0.08 to 2.80; I² = 27%, 14 studies; 873 participants; low certainty of evidence), but no evidence of effect on fasting plasma glucose. Only one study reported on dental health, with no events. No other trials reported adverse events (impaired dental health or gastrointestinal symptoms). All results were judged as low-quality evidence according to GRADE. The risk of bias was generally unclear, five studies were classified at an overall low risk of bias (low risk in at least four domains, not including other bias).

AUTHORS' CONCLUSIONS

No trials investigating the effect of added sugar on cardiovascular events or all-cause mortality were identified in our searches. Evidence is uncertain whether low intake of added sugar has an effect on risk factors for CVD; the effect was small and the clinical relevance is, therefore, uncertain. Practical ways to achieve reductions in dietary added sugar includes following current dietary recommendations. Future trials should have longer follow-up time and report on all-cause mortality and cardiovascular events in order to clarify the effect of added sugar on these outcomes. Future trials should also aim for more direct interventions and preferably be more independent of industry funding.

PoLA/CFPiP/PCS/PSLD/PSD/PSH guidelines on diagnosis and therapy of lipid disorders in Poland 2021

In Poland there are still nearly 20 million individuals with hypercholesterolaemia, most of them are unaware of their condition; that is also why only ca. 5% of patients with familial hypercholesterolaemia have been diagnosed; that is why other rare cholesterol metabolism disorders are so rarely diagnosed in Poland. Let us hope that these guidelines, being an effect of work of experts representing 6 main scientific societies, as well as the network of PoLA lipid centers being a part of the EAS lipid centers, certification of lipidologists by PoLA, or the growing number of centers for rare diseases, with a network planned by the Ministry of Health, improvements in coordinated care for patients after myocardial infarction (KOS-Zawał), reimbursement of innovative agents, as well as introduction in Poland of an effective primary prevention program, will make improvement in relation to these unmet needs in diagnostics and treatment of lipid disorders possible.

Diet and Lifestyle Factors and Risk of Atherosclerotic Cardiovascular Disease-A Prospective Cohort Study

Atherosclerotic cardiovascular disease (ACVD) is the leading cause of death worldwide. This study aimed to investigate the association between diet and lifestyle factors, beyond traditional risk factors, and the risk of incident ACVD. The Malmö Diet and Cancer study included 30,446 middle-aged individuals. Baseline examinations including a dietary assessment, questionnaire and interviews, were performed between 1991–1996. After excluding individuals with prevalent cardiovascular disease and atrial fibrillation or flutter, 26,990 participants remained. In a previously developed diet quality index, adherence to recommended intake of saturated fat (SFA), polyunsaturated fat (PUFA), fish and shellfish, fiber, vegetables and fruit, and sucrose results in one point per dietary component, with a maximum diet score of six points. Diagnosis of incident ACVD was based on validated diagnoses of coronary artery disease, atherothrombotic ischemic stroke, carotid artery disease or peripheral artery disease. Multivariable Cox regression analysis adjusting for established risk factors was performed to assess hazard ratios (HR) with 95% confidence intervals (CI). After a median follow-up of 21.1 years, 5858 (21.7%) individuals diagnosed with ACVD unrelated to atrial fibrillation or flutter were identified. Higher diet score (HR 0.94/point increase; 95% CI 0.91–0.97; p < 0.001), intake of fish and shellfish (HR 0.95/standard deviation (SD) increment, 95% CI 0.93–0.98), fiber (HR 0.93/SD increment, 95% CI 0.89–0.98) and SFA (HR 0.96/SD increment, 95% CI 0.92–0.99) consumption were associated with decreased risk for incident ACVD. High leisure-time physical activity (HR 0.82, 95% CI 0.74–0.91) was associated with reduced risk and obesity (HR 1.17, 95% CI 1.08–1.27) with increased risk of incident ACVD. The present study strengthens current recommendations of improving diet quality and increasing physical activity in preventing ACVD.

Intake of Dietary Fiber From Grains and the Risk of Hypertension in Late Midlife Women: Results From the SWAN Study

Background: The possible effects of dietary fiber intake on hypertension have not been clarified fully. The association of dietary fiber intake with hypertension risk in midlife women was analyzed in this study.

Methods: Baseline data were obtained from the Study of Women's Health Across the Nation (SWAN). Smooth curve, linear regression, and logistic regression analyses were performed to investigate the associations of four indices of daily dietary estimate (DDE) of dietary fiber (dietary fiber intake, dietary fiber intake from beans, dietary fiber intake from vegetables/fruit, and dietary fiber intake from grains) with blood pressure in midlife women. For this research purpose, diastolic blood pressure (DBP) ≥90 mmHg was defined as diastolic hypertension, and systolic blood pressure (SBP) ≥140 mmHg was defined as systolic hypertension.

Results: This study included 2,519 participants with an average age of 46. The smooth curve showed approximate negative correlations between three fiber indices (DDE dietary fiber, DDE fiber from vegetables/fruit, and DDE fiber from grains) and blood pressure, including DBP and SBP (all P < 0.005). There were also approximate negative correlations between two fiber indices (DDE dietary fiber and DDE fiber from grains) and the risk of diastolic hypertension and systolic hypertension (all P < 0.05). Furthermore, multiple linear regression analysis suggested that DDE dietary fiber (Sβ = −0.057, 95% CI −0.194 – −0.012, P = 0.027), DDE fiber from vegetables/fruit (Sβ = −0.046, 95% CI −0.263 – −0.007, P = 0.039), and DDE fiber from grains (Sβ = −0.073, 95% CI −0.600 – −0.099, P = 0.006, Model 4) were still negatively correlated with DBP after adjusting for confounding factors. Only DDE fiber from grains was independently and negatively associated with SBP (Sβ = −0.060, 95% CI −0.846 – −0.093, P = 0.015) after these same confounding factors were adjusted for. Importantly, multiple logistic regression analysis suggested that only higher DDE fiber from grains was independently associated with a reduced risk of diastolic hypertension (OR = 0.848, 95% CI 0.770–0.934, P = 0.001, Model 4) and systolic hypertension (OR = 0.906, 95% CI 0.826–0.993, P = 0.034, Model 4) after the adjustments were made for confounding factors.

Conclusions: We found that dietary fiber intake, especially DDE fiber from grains, contributes to a lower risk of systolic hypertension and diastolic hypertension in midlife women.

Evaluating agreement between bodies of evidence from randomised controlled trials and cohort studies in nutrition research: meta-epidemiological study

OBJECTIVE

To evaluate the agreement between diet-disease effect estimates of bodies of evidence from randomised controlled trials and those from cohort studies in nutrition research, and to investigate potential factors for disagreement.

DESIGN

Meta-epidemiological study.

DATA SOURCES

Cochrane Database of Systematic Reviews, and Medline.

REVIEW METHODS

Population, intervention or exposure, comparator, outcome (PI/ECO) elements from a body of evidence from cohort studies (BoE(CS)) were matched with corresponding elements of a body of evidence from randomised controlled trials (BoE(RCT)). Pooled ratio of risk ratios or difference of mean differences across all diet-disease outcome pairs were calculated. Subgroup analyses were conducted to explore factors for disagreement. Heterogeneity was assessed through I2 and τ2. Prediction intervals were calculated to assess the range of possible values for the difference in the results between evidence from randomised controlled trials and evidence from cohort studies in future comparisons.

RESULTS

97 diet-disease outcome pairs (that is, matched BoE(RCT) and BoE(CS)) were identified overall. For binary outcomes, the pooled ratio of risk ratios comparing estimates from BoE(RCT) with BoE(CS) was 1.09 (95% confidence interval 1.04 to 1.14; I2=68%; τ2=0.021; 95% prediction interval 0.81 to 1.46). The prediction interval indicated that the difference could be much more substantial, in either direction. We further explored heterogeneity and found that PI/ECO dissimilarities, especially for the comparisons of dietary supplements in randomised controlled trials and nutrient status in cohort studies, explained most of the differences. When the type of intake or exposure between both types of evidence was identical, the estimates were similar. For continuous outcomes, small differences were observed between randomised controlled trials and cohort studies.

CONCLUSION

On average, the difference in pooled results between estimates from BoE(RCT) and BoE(CS) was small. But wide prediction intervals and some substantial statistical heterogeneity in cohort studies indicate that important differences or potential bias in individual comparisons or studies cannot be excluded. Observed differences were mainly driven by dissimilarities in population, intervention or exposure, comparator, and outcome. These findings could help researchers further understand the integration of such evidence into prospective nutrition evidence syntheses and improve evidence based dietary guidelines.

The Role of Gut Microbiota on Cholesterol Metabolism in Atherosclerosis

Hypercholesterolemia plays a causal role in the development of atherosclerosis and is one of the main risk factors for cardiovascular disease (CVD), the leading cause of death worldwide especially in developed countries. Current data show that the role of microbiota extends beyond digestion by being implicated in several metabolic and inflammatory processes linked to several diseases including CVD. Studies have reported associations between bacterial metabolites and hypercholesterolemia. However, such associations remain poorly investigated and characterized. In this review, the mechanisms of microbial derived metabolites such as primary and secondary bile acids (BAs), trimethylamine N-oxide (TMAO), and short-chain fatty acids (SCFAs) will be explored in the context of cholesterol metabolism. These metabolites play critical roles in maintaining cardiovascular health and if dysregulated can potentially contribute to CVD. They can be modulated via nutritional and pharmacological interventions such as statins, prebiotics, and probiotics. However, the mechanisms behind these interactions also remain unclear, and mechanistic insights into their impact will be provided. Therefore, the objectives of this paper are to present current knowledge on potential mechanisms whereby microbial metabolites regulate cholesterol homeostasis and to discuss the feasibility of modulating intestinal microbes and metabolites as a novel therapeutic for hypercholesterolemia.

Dietary fiber intake from fresh and preserved food and risk of nasopharyngeal carcinoma: observational evidence from a Chinese population

Background

The role of dietary fiber intake on risk of nasopharyngeal carcinoma (NPC) remains unclear. We examined the associations of dietary fiber intake on the risk of NPC adjusting for a comprehensive list of potential confounders.

Methods

Using data from a multicenter case-control study, we included 815 histologically confirmed NPC incident cases and 1502 controls in Hong Kong, China recruited in 2014–2017. Odds ratios (ORs) of NPC (cases vs controls) for dietary fiber intake from different sources at different life periods (age 13–18, age 19–30, and 10 years before recruitment) were evaluated using unconditional logistic regression, adjusting for sex, age, socioeconomic status, smoking and drinking status, occupational hazards, family history of cancer, salted fish, and total energy intake in Model 1, Epstein-Barr virus viral capsid antigen serological status in Model 2, and duration of sun exposure and circulating 25-hydroxyvitamin D in Model 3.

Results

Higher intake of total dietary fiber 10 years before recruitment was significantly associated with decreased NPC risk, with demonstrable dose-response relationship (P-values for trend = 0.001, 0.020 and 0.024 in Models 1–3, respectively). The adjusted ORs (95% CI) in the highest versus the lowest quartile were 0.51 (0.38–0.69) in Model 1, 0.48 (0.33–0.69) in Model 2, and 0.48 (0.33–0.70) in Model 3. However, the association was less clear after adjustment of other potential confounders (e.g. EBV) in the two younger periods (age of 13–18 and 19–30 years). Risks of NPC were significantly lower for dietary fiber intake from fresh vegetables and fruits and soybean products over all three periods, with dose-response relationships observed in all Models (P-values for trend for age 13–18, age 19–30 and 10 years before recruitment were, respectively, 0.002, 0.009 and 0.001 for Model1; 0.020, 0.031 and 0.003 for Model 2; and 0.022, 0.037 and 0.004 for Model 3). No clear association of NPC risk with dietary fiber intake from preserved vegetables, fruits and condiments was observed.

Conclusion

Our study has shown the protective role of dietary fiber from fresh food items in NPC risk, but no association for total dietary fiber intake was observed, probably because total intake also included intake of preserved food. Further studies with detailed dietary information and in prospective settings are needed to confirm this finding, and to explore the possible underlying biological mechanisms.

The role of diet-derived short-chain fatty acids in regulating cardiac pressure overload

Heart failure (HF) is one of the leading causes of mortality and morbidity in the modern world whose increasing prevalence is associated with "Western" diet and sedentary lifestyles. Of particular concern is the increasing burden of HF with preserved ejection fraction (HFpEF) that involves complex pathophysiology and is difficult to treat. Pressure overload caused by hypertension (HTN) is the predominant driver of cardiac injury, left ventricular hypertrophy, and fibrosis that progresses to diastolic dysfunction and ultimately HFpEF. Although pharmacological control of blood pressure may affect the degree of pressure overload, such therapies are largely ineffective in established HFpEF, and there is a need to modulate the festering inflammatory and fibrotic response to injury to halt and perhaps reverse pathology. An emerging literature indicates potentially important links between the gut microbiota, dietary soluble fiber, and microbiota-derived metabolites that modulate blood pressure and the immune response. In particular, high-fiber diets demonstrate protective properties in systemic hypertension and left-sided cardiac pathology, and this action is closely associated with short-chain fatty acid (SCFA)-producing bacteria. Mechanisms underlying the beneficial action of SCFAs in immunity and the systemic circulation could potentially be applied to the treatment of hypertension and the cardiac damage it causes. In this review, we discuss the potential beneficial effects of SCFAs, with an emphasis on mechanisms that are involved in cardiac responses to pressure overload.

Potato Fibers Have Positive Effects on Subjective Appetite Sensations in Healthy Men, but Not on Fecal Fat Excretion: A Randomized Controlled Single-Blind Crossover Trial

Dietary fibers can affect appetite and gut metabolism, but the effect of the novel potato fibers FiberBind and rhamnogalacturonan I (RG-I) is unknown. We, therefore, aimed to investigate the effect of daily intake of FiberBind and RG-I on appetite sensations and fecal fat excretion. In a single-blinded, randomized, three-way crossover trial, wheat buns with FiberBind, RG-I, or low fiber (control) were consumed by 18 healthy men during a 21-day period. Appetite sensation and blood samples during a 3 h meal test, fecal fat content, and ad libitum energy intake were assessed after each period. Compared to RG-I and control, FiberBind caused a higher composite satiety score (6% ± 2% and 5% ± 2%), lower prospective food consumption (5% ± 2% and 6% ± 2%), and lower desire to eat (7% ± 3% and 6% ± 3%) (all p < 0.05). FiberBind also caused higher satiety (6% ± 2%) and fullness (9% ± 3%) compared to RG-I (all p < 0.01). No effects on fecal fat excretion or energy intake were found. The RG-I fiber caused higher postprandial glucose concentration compared to FiberBind (p < 0.05) and higher insulin concentration at 180 min compared to control (p < 0.05). Compared to the control, RG-I and FiberBind lowered peak insulin concentration (both p < 0.05) and delayed time to peak for glucose (both p < 0.05). In conclusion, FiberBind intake could be beneficial for appetite regulation, but neither FiberBind nor RG-I affected fecal fat excretion or energy intake.

Relation of Different Fruit and Vegetable Sources With Incident Cardiovascular Outcomes: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

Background Public health policies reflect concerns that certain fruit sources may not have the intended benefits and that vegetables should be preferred to fruit. We assessed the relation of fruit and vegetable sources with cardiovascular outcomes using a systematic review and meta-analysis of prospective cohort studies. Methods and Results MEDLINE, EMBASE, and Cochrane were searched through June 3, 2019. Two independent reviewers extracted data and assessed study quality (Newcastle-Ottawa Scale). Data were pooled (fixed effects), and heterogeneity (Cochrane-Q and I2) and certainty of the evidence (Grading of Recommendations Assessment, Development, and Evaluation) were assessed. Eighty-one cohorts involving 4 031 896 individuals and 125 112 cardiovascular events were included. Total fruit and vegetables, fruit, and vegetables were associated with decreased cardiovascular disease (risk ratio, 0.93 [95% CI, 0.89-0.96]; 0.91 [0.88-0.95]; and 0.94 [0.90-0.97], respectively), coronary heart disease (0.88 [0.83-0.92]; 0.88 [0.84-0.92]; and 0.92 [0.87-0.96], respectively), and stroke (0.82 [0.77-0.88], 0.82 [0.79-0.85]; and 0.88 [0.83-0.93], respectively) incidence. Total fruit and vegetables, fruit, and vegetables were associated with decreased cardiovascular disease (0.89 [0.85-0.93]; 0.88 [0.86-0.91]; and 0.87 [0.85-0.90], respectively), coronary heart disease (0.81 [0.72-0.92]; 0.86 [0.82-0.90]; and 0.86 [0.83-0.89], respectively), and stroke (0.73 [0.65-0.81]; 0.87 [0.84-0.91]; and 0.94 [0.90-0.99], respectively) mortality. There were greater benefits for citrus, 100% fruit juice, and pommes among fruit sources and allium, carrots, cruciferous, and green leafy among vegetable sources. No sources showed an adverse association. The certainty of the evidence was "very low" to "moderate," with the highest for total fruit and/or vegetables, pommes fruit, and green leafy vegetables. Conclusions Fruits and vegetables are associated with cardiovascular benefit, with some sources associated with greater benefit and none showing an adverse association. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT03394339.

The Role of Specific Components of a Plant-Based Diet in Management of Dyslipidemia and the Impact on Cardiovascular Risk

Convincing evidence supports the intake of specific food components, food groups, or whole dietary patterns to positively influence dyslipidemia and to lower risk of cardiovascular diseases (CVD). Specific macro- and micro-components of a predominantly plant-based dietary pattern are vegetable fats, dietary fibers, and phytonutrients such as phytosterols. This review summarizes the current knowledge regarding effects of these components on lowering blood lipids, i.e., low-density lipoprotein cholesterol (LDL-C) and on reducing CVD risk. The beneficial role of a plant-based diet on cardiovascular (CV) health has increasingly been recognized. Plant-based dietary patterns include a Mediterranean and Nordic diet pattern, the dietary approaches to stop hypertension (DASH), and Portfolio diet, as well as vegetarian- or vegan-type diet patterns. These diets have all been found to lower CVD-related risk factors like blood LDL-C, and observational study evidence supports their role in lowering CVD risk. These diet patterns are not only beneficial for dyslipidemia management and prevention of CVD but further contribute to reducing the impact of food choices on environmental degradation. Hence, the CV health benefits of a predominantly plant-based diet as a healthy and environmentally sustainable eating pattern are today recommended by many food-based dietary as well as clinical practice guidelines.

Draft for internal testing Scientific Committee guidance on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments

EFSA requested its Scientific Committee to prepare a guidance document on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments. The guidance document provides an introduction to epidemiological studies and illustrates the typical biases of the different epidemiological study designs. It describes key epidemiological concepts relevant for evidence appraisal. Regarding study reliability, measures of association, exposure assessment, statistical inferences, systematic error and effect modification are explained. Regarding study relevance, the guidance describes the concept of external validity. The principles of appraising epidemiological studies are illustrated, and an overview of Risk of Bias (RoB) tools is given. A decision tree is developed to assist in the selection of the appropriate Risk of Bias tool, depending on study question, population and design. The customisation of the study appraisal process is explained, detailing the use of RoB tools and assessing the risk of bias in the body of evidence. Several examples of appraising experimental and observational studies using a Risk of Bias tool are annexed to the document to illustrate the application of the approach. This document constitutes a draft that will be applied in EFSA's assessments during a 1-year pilot phase and be revised and complemented as necessary. Before finalisation of the document, a public consultation will be launched.

The associations of major foods and fibre with risks of ischaemic and haemorrhagic stroke: a prospective study of 418 329 participants in the EPIC cohort across nine European countries

AIM

To investigate the associations between major foods and dietary fibre with subtypes of stroke in a large prospective cohort.

METHODS AND RESULTS

We analysed data on 418 329 men and women from nine European countries, with an average of 12.7 years of follow-up. Diet was assessed using validated country-specific questionnaires which asked about habitual intake over the past year, calibrated using 24-h recalls. Multivariable-adjusted Cox regressions were used to estimate hazard ratios (HRs) for ischaemic and haemorrhagic stroke associated with consumption of red and processed meat, poultry, fish, dairy foods, eggs, cereals, fruit and vegetables, legumes, nuts and seeds, and dietary fibre. For ischaemic stroke (4281 cases), lower risks were observed with higher consumption of fruit and vegetables combined (HR; 95% CI per 200 g/day higher intake, 0.87; 0.82-0.93, P-trend < 0.001), dietary fibre (per 10 g/day, 0.77; 0.69-0.86, P-trend < 0.001), milk (per 200 g/day, 0.95; 0.91-0.99, P-trend = 0.02), yogurt (per 100 g/day, 0.91; 0.85-0.97, P-trend = 0.004), and cheese (per 30 g/day, 0.88; 0.81-0.97, P-trend = 0.008), while higher risk was observed with higher red meat consumption which attenuated when adjusted for the other statistically significant foods (per 50 g/day, 1.07; 0.96-1.20, P-trend = 0.20). For haemorrhagic stroke (1430 cases), higher risk was associated with higher egg consumption (per 20 g/day, 1.25; 1.09-1.43, P-trend = 0.002).

CONCLUSION

Risk of ischaemic stroke was inversely associated with consumption of fruit and vegetables, dietary fibre, and dairy foods, while risk of haemorrhagic stroke was positively associated with egg consumption. The apparent differences in the associations highlight the importance of examining ischaemic and haemorrhagic stroke subtypes separately.

Dietary Fiber, Gut Microbiota, and Metabolic Regulation-Current Status in Human Randomized Trials

New knowledge about the gut microbiota and its interaction with the host's metabolic regulation has emerged during the last few decades. Several factors may affect the composition of the gut microbiota, including dietary fiber. Dietary fiber is not hydrolyzed by human digestive enzymes, but it is acted upon by gut microbes, and metabolites like short-chain fatty acids are produced. The short-chain fatty acids may be absorbed into the circulation and affect metabolic regulation in the host or be a substrate for other microbes. Some studies have shown improved insulin sensitivity, weight regulation, and reduced inflammation with increases in gut-derived short-chain fatty acids, all of which may reduce the risk of developing metabolic diseases. To what extent a dietary intervention with fiber may affect the human gut microbiota and hence metabolic regulation, is however, currently not well described. The aim of the present review is to summarize recent research on human randomized, controlled intervention studies investigating the effect of dietary fiber on gut microbiota and metabolic regulation. Metabolic regulation is discussed with respect to markers relating to glycemic regulation and lipid metabolism. Taken together, the papers on which the current review is based, suggest that dietary fiber has the potential to change the gut microbiota and alter metabolic regulation. However, due to the heterogeneity of the studies, a firm conclusion describing the causal relationship between gut microbiota and metabolic regulation remains elusive.

The Effect of Isolated and Synthetic Dietary Fibers on Markers of Metabolic Diseases in Human Intervention Studies: A Systematic Review

Observational studies provide strong evidence for the health benefits of dietary fiber (DF) intake; however, human intervention studies that supplement isolated and synthetic DFs have shown inconsistent results. Therefore, we conducted a systematic review to summarize the effects of DF supplementation on immunometabolic disease markers in intervention studies in healthy adults, and considered the role of DF dose, DF physicochemical properties, intervention duration, and the placebo used. Five databases were searched for studies published from 1990 to 2018 that assessed the effect of DF on immunometabolic markers. Eligible studies were those that supplemented isolated or synthetic DFs for ≥2 wk and reported baseline data to assess the effect of the placebo. In total, 77 publications were included. DF supplementation reduced total cholesterol (TC), LDL cholesterol, HOMA-IR, and insulin AUC in 36-49% of interventions. In contrast, <20% of the interventions reduced C-reactive protein (CRP), IL-6, glucose, glucose AUC, insulin, HDL cholesterol, and triglycerides. A higher proportion of interventions showed an effect if they used higher DF doses for CRP, TC, and LDL cholesterol (40-63%), viscous and mixed plant cell wall DFs for TC and LDL cholesterol (>50%), and longer intervention durations for CRP and glucose (50%). Half of the placebo-controlled studies used digestible carbohydrates as the placebo, which confounded findings for IL-6, glucose AUC, and insulin AUC. In conclusion, interventions with isolated and synthetic DFs resulted mainly in improved cholesterol concentrations and an attenuation of insulin resistance, whereas markers of dysglycemia and inflammation were largely unaffected. Although more research is needed to make reliable recommendations, a more targeted supplementation of DF with specific physicochemical properties at higher doses and for longer durations shows promise in enhancing several of its health effects.

Application of nutrient essentiality criteria to dietary carbohydrates

The purpose of the present review is to describe how human physiology at very low carbohydrate intakes relates to the criteria for nutritional essentiality. Although we did not limit ourselves to one particular type or function of carbohydrates, we did primarily focus on glucose utilisation as that function was used to determine the recommended daily allowance. In the general population, the human body is able to endogenously synthesise carbohydrates, and does not show signs of deficiency in the absence of dietary carbohydrates. However, in certain genetic defects, such as glycogen storage disease type I, absence of dietary carbohydrates causes abnormalities that are resolved with dietary supplementation of carbohydrates. Therefore, dietary carbohydrates may be defined as conditionally essential nutrients because they are nutrients that are not required in the diet for the general population but are required for specific subpopulations. Ketosis may be considered a physiological normal state due to its occurrence in infants in addition to at very low carbohydrate intakes. Although sources of dietary carbohydrates can provide beneficial micronutrients, no signs of micronutrient deficiencies have been reported in clinical trials of low-carbohydrate ketogenic diets. Nonetheless, more research is needed on how micronutrient requirements can change depending on the dietary and metabolic context. More research is also needed on the role of dietary fibre during a low-carbohydrate ketogenic diet as the beneficial effects of dietary fibre were determined on a standard diet and several studies have shown beneficial effects of decreasing non-digestible carbohydrates.

Obesity in achondroplasia patients: from evidence to medical monitoring

Achondroplasia is a rare genetic disease representing the most common form of short-limb dwarfism. It is characterized by bone growth abnormalities that are well characterized and by a strong predisposition to abdominal obesity for which causes are unknown. Despite having aroused interest at the end of the 20 h century, there are still only very little data available on this aspect of the pathology. Today, interest is rising again, and some studies are now proposing mechanistic hypotheses and guidance for patient management. These data confirm that obesity is a major health problem in achondroplasia necessitating an early yet complex clinical management. Anticipatory care should be directed at identifying children who are at high risk to develop obesity and intervening to prevent the metabolic complications in adults. In this review, we are regrouping available data characterizing obesity in achondroplasia and we are identifying the current tools used to monitor obesity in these patients.

Cholesterol versus Inflammation as Cause of Chronic Diseases

Tsoupras and colleagues have postulated, in a recent review in Nutrients, that the key to reducing the incidence of cardiovascular disease is to control the activities of inflammatory mediators such as platelet-activating factor (PAF) by diet, exercise, and healthy lifestyle choices [...].

Implementation of a Brazilian Cardioprotective Nutritional (BALANCE) Program for improvement on quality of diet and secondary prevention of cardiovascular events: A randomized, multicenter trial

BACKGROUND

Appropriate dietary recommendations represent a key part of secondary prevention in cardiovascular disease (CVD). We evaluated the effectiveness of the implementation of a nutritional program on quality of diet, cardiovascular events, and death in patients with established CVD.

METHODS

In this open-label, multicenter trial conducted in 35 sites in Brazil, we randomly assigned (1:1) patients aged 45 years or older to receive either the BALANCE Program (experimental group) or conventional nutrition advice (control group). The BALANCE Program included a unique nutritional education strategy to implement recommendations from guidelines, adapted to the use of affordable and regional foods. Adherence to diet was evaluated by the modified Alternative Healthy Eating Index. The primary end point was a composite of all-cause mortality, cardiovascular death, cardiac arrest, myocardial infarction, stroke, myocardial revascularization, amputation, or hospitalization for unstable angina. Secondary end points included biochemical and anthropometric data, and blood pressure levels.

RESULTS

From March 5, 2013, to Abril 7, 2015, a total of 2534 eligible patients were randomly assigned to either the BALANCE Program group (n = 1,266) or the control group (n = 1,268) and were followed up for a median of 3.5 years. In total, 235 (9.3%) participants had been lost to follow-up. After 3 years of follow-up, mean modified Alternative Healthy Eating Index (scale 0-70) was only slightly higher in the BALANCE group versus the control group (26.2 ± 8.4 vs 24.7 ± 8.6, P < .01), mainly due to a 0.5-serving/d greater intake of fruits and of vegetables in the BALANCE group. Primary end point events occurred in 236 participants (18.8%) in the BALANCE group and in 207 participants (16.4%) in the control group (hazard ratio, 1.15; 95% CI 0.95-1.38; P = .15). Secondary end points did not differ between groups after follow-up.

CONCLUSIONS

The BALANCE Program only slightly improved adherence to a healthy diet in patients with established CVD and had no significant effect on the incidence of cardiovascular events or death.

Effects of Nutritional Supplements and Dietary Interventions on Cardiovascular Outcomes: An Umbrella Review and Evidence Map

BACKGROUND

The role of nutritional supplements and dietary interventions in preventing mortality and cardiovascular disease (CVD) outcomes is unclear.

PURPOSE

To examine evidence about the effects of nutritional supplements and dietary interventions on mortality and cardiovascular outcomes in adults.

DATA SOURCES

PubMed, CINAHL, and the Cochrane Library from inception until March 2019; ClinicalTrials.gov (10 March 2019); journal Web sites; and reference lists.

STUDY SELECTION

English-language, randomized controlled trials (RCTs) and meta-analyses of RCTs that assessed the effects of nutritional supplements or dietary interventions on all-cause mortality or cardiovascular outcomes, such as death, myocardial infarction, stroke, and coronary heart disease.

DATA EXTRACTION

Two independent investigators abstracted data, assessed the quality of evidence, and rated the certainty of evidence.

DATA SYNTHESIS

Nine systematic reviews and 4 new RCTs were selected that encompassed a total of 277 trials, 24 interventions, and 992 129 participants. A total of 105 meta-analyses were generated. There was moderate-certainty evidence that reduced salt intake decreased the risk for all-cause mortality in normotensive participants (risk ratio [RR], 0.90 [95% CI, 0.85 to 0.95]) and cardiovascular mortality in hypertensive participants (RR, 0.67 [CI, 0.46 to 0.99]). Low-certainty evidence showed that omega-3 long-chain polyunsaturated fatty acid (LC-PUFA) was associated with reduced risk for myocardial infarction (RR, 0.92 [CI, 0.85 to 0.99]) and coronary heart disease (RR, 0.93 [CI, 0.89 to 0.98]). Folic acid was associated with lower risk for stroke (RR, 0.80 [CI, 0.67 to 0.96]; low certainty), whereas calcium plus vitamin D increased the risk for stroke (RR, 1.17 [CI, 1.05 to 1.30]; moderate certainty). Other nutritional supplements, such as vitamin B6, vitamin A, multivitamins, antioxidants, and iron and dietary interventions, such as reduced fat intake, had no significant effect on mortality or cardiovascular disease outcomes (very low- to moderate-certainty evidence).

LIMITATIONS

Suboptimal quality and certainty of evidence.

CONCLUSION

Reduced salt intake, omega-3 LC-PUFA use, and folate supplementation could reduce risk for some cardiovascular outcomes in adults. Combined calcium plus vitamin D might increase risk for stroke.

PRIMARY FUNDING SOURCE

None.

Effects of the Order of Physical Exercises on Body Composition, Physical Fitness, and Cardiometabolic Risk in Adolescents Participating in an Interdisciplinary Program Focusing on the Treatment of Obesity

The main objective of this study was to investigate the effects of the order of physical exercises on body composition, physical fitness, and cardiometabolic risk in adolescents participating in an interdisciplinary program focusing on the treatment of obesity. The final 12-week analyses involved 33 female adolescents who were split into two groups of concurrent training (CT): resistance plus aerobic training and aerobic plus resistance training, with equalization performed in all physical exercises. The only difference between the two groups was the order in which the exercises were performed. The results showed reductions in fat mass, body fat, and waist circumference, as well as increases in musculoskeletal mass and resting metabolic rate (p < 0.05) following the multiprofessional intervention period. However, no significant differences were observed in regard to body mass, body mass index, neck circumference, or arm circumference (p > 0.05). Maximal isometric strength and maximal oxygen consumption showed significant increases after the intervention period (p < 0.05). There were reductions in insulin, HOMA-IR, total cholesterol, triglycerides, and low-density lipoproteins (p < 0.05), and an interaction within the resistance plus aerobic training group showed lower values for triglycerides when compared to itself (p = 0.002). No difference was found in fasting glycemia for either group (p > 0.05). It is worth noting that the equalization training variables presented no differences between the two groups (p > 0.05). Based on these results, both CT methods were found to be effective in promoting health parameters in overweight and obese female adolescents, and triglyceride values decreased more in the resistance plus aerobic group. Future studies with larger samples and feeding control should be conducted to confirm or refute our findings.

Role of Gut Microbiota-Generated Short-Chain Fatty Acids in Metabolic and Cardiovascular Health

Purpose of this Review

This review assesses the latest evidence linking short-chain fatty acids (SCFA) with host metabolic health and cardiovascular disease (CVD) risk and presents the latest evidence on possible biological mechanisms.

Recent Findings

SCFA have a range of effects locally in the gut and at both splanchnic and peripheral tissues which together appear to induce improved metabolic regulation and have direct and indirect effects on markers of CVD risk.

Summary

SCFA produced primarily from the microbial fermentation of dietary fibre appear to be key mediators of the beneficial effects elicited by the gut microbiome. Not only does dietary fibre fermentation regulate microbial activity in the gut, SCFA also directly modulate host health through a range of tissue-specific mechanisms related to gut barrier function, glucose homeostasis, immunomodulation, appetite regulation and obesity. With the increasing burden of obesity worldwide, the role for gut microbiota-generated SCFA in protecting against the effects of energy dense diets offers an intriguing new avenue for regulating metabolic health and CVD risk.