Whole-grain intake and carotid artery atherosclerosis in a multiethnic cohort: the Insulin Resistance Atherosclerosis Study

Association between whole-grain consumption and carotid atherosclerosis: the Tianjin chronic low-grade systemic inflammation and health (TCLSIH) cohort study

Background: Whole-grain contains a range of beneficial nutrients, which are thought to play a role in the prevention of chronic diseases. However, the association between whole-grain consumption and the risk of developing carotid atherosclerosis (CA) has not been sufficiently elucidated. We, therefore, conducted this study to investigate the relationship between whole-grain consumption and CA in the general adult population. Methods: This prospective cohort study included a total of 2166 participants (19.2-84.6 years, 55.0% men) without a history of cardiovascular disease, cancer, and CA at baseline. A validated food frequency questionnaire was used to assess whole-grain consumption. Measurements of CA include carotid intima-media thickness (IMT) and carotid plaque. IMT thickening is defined as: IMT ≥ 1.0 mm or a carotid bifurcation IMT ≥ 1.2 mm. Carotid plaque is defined as: distinct area protruding ≥1.5 mm into the vascular lumen of the carotid artery. Cox proportional hazards regression models were used to examine the association of whole-grain consumption with incident CA. Results: A total of 538 (341 men) first incident cases of CA occurred during 5585 person-years of follow-up (median follow-up: 4.2 years). After adjusting for demographic characteristics, lifestyle factors, dietary intake, individual and family history of disease, the multivariable HRs (95% CIs) for incident CA were 1.00 (reference) for <1 time per week, 1.10 (0.85, 1.43) for 1 time per week, 0.95 (0.75, 1.20) for 2-6 times per week, and 1.12 (0.80, 1.56) for ≥1 times per day, respectively (P for trend = 0.99). Similar results were observed in stratified analyses by the main covariates and sensitivity analyses. Conclusion: Our data indicate that whole-grain consumption had no significant association with the risk of CA in an adult Chinese population. In our study population, there is a low consumption of whole-grain, which may limit our ability to see an association. Further cohort studies or randomized controlled trials are needed to confirm our results.

Vascular Aging: Assessment and Intervention

Vascular aging represents a collection of structural and functional changes in a blood vessel with advancing age, including increased stiffness, vascular wall remodeling, loss of angiogenic ability, and endothelium-dependent vasodilation dysfunction. These age-related alterations may occur earlier in those who are at risk for or have cardiovascular diseases, therefore, are defined as early or premature vascular aging. Vascular aging contributes independently to cardio-cerebral vascular diseases (CCVDs). Thus, early diagnosis and interventions targeting vascular aging are of paramount importance in the delay or prevention of CCVDs. Here, we review the direct assessment of vascular aging by examining parameters that reflect changes in structure, function, or their compliance with age including arterial wall thickness and lumen diameter, endothelium-dependent vasodilation, arterial stiffness as well as indirect assessment through pathological studies of biomarkers including endothelial progenitor cell, lymphocytic telomeres, advanced glycation end-products, and C-reactive protein. Further, we evaluate how different types of interventions including lifestyle mediation, such as caloric restriction and salt intake, and treatments for hypertension, diabetes, and hyperlipidemia affect age-related vascular changes. As a single parameter or intervention targets only a certain vascular physiological change, it is recommended to use multiple parameters to evaluate and design intervention approaches accordingly to prevent systemic vascular aging in clinical practices or population-based studies.

Dietary modulation of advanced glycation end products metabolism on carotid intima-media thickness in type 2 diabetes patients: From the CORDIOPREV study

BACKGROUND

Advanced glycation end products (AGEs) are pro-oxidant and cytotoxic compounds involved in the progression of chronic diseases as cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM). The total body burden of AGEs also depend of those consume through the diet. Our aim was to analyze whether the reduction of AGE levels, after the consumption of two-healthy diets were associated with a greater decrease of intima-media thickness of both common carotid arteries (IMT-CC) in patients with T2DM and coronary heart disease (CHD).

METHODS

540 CHD patients with T2DM, at baseline, from the CORDIOPREV study, were divided into two groups: (1) Responders, patients whose IMT-CC was reduced or not changed after dietary intervention and (2) Non-responders, patients whose IMT-CC was increased after dietary intervention. A total of 423 completed baseline and the 5-year follow-up carotid ultrasounds were analyzed in this study.

RESULTS

Our data showed that Responders, despite had a higher baseline IMT-CC and serum methylglyoxal (MG) levels than Non-responders, showed a reduction of serum levels of this glycotoxin after dietary intervention. Conversely, in patients whose IMT-CC was increased after dietary intervention (Non-responders), serum MG levels were increased. Moreover, an increase of circulating level of AGEs (and in particular, MG), after dietary intervention, could be considered a risk factor for the progression of atherosclerosis in patients with T2DM and CHD.

CONCLUSION

These results support the importance of identifying underlying mechanisms in the context of secondary prevention of CVD that would provide therapeutic targets to reduce the high risk of cardiovascular events of these patients.

CLINICAL TRIAL REGISTRATION-URL

https://clinicaltrials.gov/ct2/show/NCT00924937. Unique Identifier: NCT00924937.

High-quality intake of carbohydrates is associated with lower prevalence of subclinical atherosclerosis in femoral arteries: The AWHS study

BACKGROUND AND AIMS

High-quality of the carbohydrates consumed, apart from their total amount, appear to protect from cardiovascular disease (CVD). However, the relationship between the quality of carbohydrates and the early appearance of atherosclerosis has not yet been described. Our objective was to estimate the association between the quality of dietary carbohydrates and subclinical atherosclerosis in femoral and carotid arteries.

METHODS

Cross-sectional study of femoral and carotid atherosclerosis assessed using ultrasounds of 2074 middle-aged males, 50.9 (SD 3.9) years old, with no previous CVD, and pertaining to the Aragon Workers' Health Study (AWHS) cohort. Food frequency questionnaires were used to calculate a carbohydrate quality index (CQI) defined as: consumption of dietary fiber, a lower glycemic index, the ratio of whole grains/total grains, and the ratio of solid carbohydrates/total carbohydrates. The presence of plaques across four CQI intervals was studied using adjusted logistic regression models.

RESULTS

The CQI showed a direct inverse association with subclinical atherosclerosis in femoral territories. Participants with a higher consumption of high-quality carbohydrates (13-15 points) were less likely to have femoral plaques when compared with participants in the lowest index interval (4-6 points) (OR = 0.59; 95% CI = 0.39, 0.89; p = 0.005). No association was found between the CQI and the presence of subclinical atherosclerosis in carotid territories. A lower consumption of high-quality carbohydrates tended to be associated with a greater atherosclerosis extension, considered as the odds for having more affected territories (p = 0.011).

CONCLUSIONS

Among middle-aged males, a high-quality intake of carbohydrates is associated with a lower prevalence of femoral artery subclinical atherosclerosis when compared with a lower consumption. Thus, indicating an early relationship between the quality of carbohydrates and the development of CVD.

Light-To-Moderate Raw Garlic Consumption Frequency Is Inversely Associated With Thickened Carotid Intima-Media Thickness: A Population-Based Study

Background: Previous animal and clinical studies have reported beneficial effects of garlic preparations on carotid intima-media thickness (cIMT). However, no epidemiological study has yet investigated the association between dietary raw garlic consumption and cIMT in the general population. The objective of this study was investigating the association between dietary raw garlic consumption and thickened cIMT in Chinese adults. Methods: This cross-sectional study used data from the Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study. A total of 4,329 general adults from 2015 to 2017 were included in this study. Frequency of consumption of raw garlic was summarized as four categories for analysis: < 1 time/week, 1 time/week, 2-3 times/week, ≥4 times/week with a validated food frequency questionnaire. The thickened cIMT was defined as common carotid artery IMT ≥ 1.0 mm or a carotid bifurcation IMT ≥ 1.2 mm by ultrasonography. Multivariable logistic regression analysis was used to examine the association between frequency of raw garlic consumption and thickened cIMT. Results: The prevalence of thickened cIMT is 22.9% among these participants. The adjusted odds ratios (95% confidence intervals) associated with the different frequencies were 1.00 (reference) for < 1 time/week, 0.74 (0.59, 0.94) for 1 time/week, 0.71 (0.55, 0.92) for 2-3 times/week, and 0.94 (0.71, 1.25) for ≥ 4 times/week. Conclusions: Light-to-moderate raw garlic consumption was inversely associated with thickened cIMT, whereas greater raw garlic consumption (i.e., ≥4 times/week) was not associated with thickened cIMT. Future longitudinal studies should be conducted to test these findings.

Traditional Risk Factors are Causally Related to Carotid Intima-Media Thickness Progression: Inferences from Observational Cohort Studies and Interventional Trials

In the present review, associations between traditional vascular risk factors (VRFs) and carotid intimamedial thickness progression (C-IMTp) as well as the effects of therapies for VRFs control on C-IMTp were appraised to infer causality between each VRF and C-IMTp. Cohort studies indicate that smoking, binge drinking, fatness, diabetes, hypertension and hypercholesterolemia are associated with accelerated C-IMTp. An exception is physical activity, with mixed data. Interventions for the control of obesity, diabetes, hypertension and hypercholesterolemia decelerate C-IMTp. Conversely, scarce information is available regarding the effect of smoking cessation, stop of excessive alcohol intake and management of the metabolic syndrome. Altogether, these data support a causative role of several traditional VRFs on C-IMTp. Shortcomings in study design and/or ultrasonographic protocols may account for most negative studies, which underlines the importance of careful consideration of methodological aspects in investigations using C-IMTp as the outcome.

Influence of Bioactive Nutrients on the Atherosclerotic Process: A Review

The protective effects of a dietary intervention as a useful tool in the prevention of atherosclerosis disease has gained greater attention in recent years. Several epidemiological studies have demonstrated the importance of diet in reducing expensive treatments or possible undesirable side effects. The main aim of this review is to examine the effects of specific nutrients on the development and progression of atherosclerosis in patients with cardiovascular disease. Various mechanisms have been proposed to explain the cardioprotective effect of different nutrients. In this sense, results have shown stabilization of vulnerable atherosclerotic plaques or downregulation of biomarkers related to inflammation through nutrients such as Omega-3 polyunsaturated fatty acids, hydroxytyrosol of extra virgin olive oil, lycopen, phytosterols of plants, or flavonols of fruits and vegetables, among others. The accumulated evidence on the anti-inflammatory effects related to these nutrients is summarized in the present review.

Processing of oat: the impact on oat's cholesterol lowering effect

Epidemiological and interventional studies have clearly demonstrated the beneficial impact of consuming oat and oat-based products on serum cholesterol and other markers of cardiovascular disease. The cholesterol-lowering effect of oat is thought to be associated with the β-glucan it contains. However, not all food products containing β-glucan seem to lead to the same health outcome. Overall, highly processed β-glucan sources (where the oat tissue is highly disrupted) appear to be less effective at reducing serum cholesterol, but the reasons are not well understood. Therefore, the mechanisms involved still need further clarification. The purpose of this paper is to review current evidence of the cholesterol-lowering effect of oat in the context of the structure and complexity of the oat matrix. The possibility of a synergistic action and interaction between the oat constituents promoting hypocholesterolaemia is also discussed. A review of the literature suggested that for a similar dose of β-glucan, (1) liquid oat-based foods seem to give more consistent, but moderate reductions in cholesterol than semi-solid or solid foods where the results are more variable; (2) the quantity of β-glucan and the molecular weight at expected consumption levels (∼3 g day-1) play a role in cholesterol reduction; and (3) unrefined β-glucan-rich oat-based foods (where some of the plant tissue remains intact) often appear more efficient at lowering cholesterol than purified β-glucan added as an ingredient.

Influence of fermentation and other processing steps on the folate content of a traditional African cereal-based fermented food

Folate deficiency can cause a number of diseases including neural tube defects and megaloblastic anemia, and still occurs in both developed and developing countries. Cereal-based food products are staple foods in many countries, and may therefore be useful sources of folate. The production of folate by microorganisms has been demonstrated in some cereal-based fermented foods, but has never been studied in a traditional African cereal based food spontaneously fermented. The microbiota of ben-saalga, a pearl-millet based fermented porridge frequently consumed in Burkina Faso, has a good genetic potential for the synthesis of folate, but the folate content of ben-saalga is rather low, suggesting that folate is lost during the different processing steps. The aim of this study was therefore to monitor changes in folate content during the different steps of preparing ben-saalga, from pearl-millet grains to porridge. Traditional processing involves seven different steps: washing, soaking, grinding, kneading, sieving, (spontaneous) fermentation, and cooking. Two type of porridge were prepared, one using a process adapted from the traditional process, the other a modified process based on fermentation by backslopping. Dry matter and total folate contents were measured at each step, and a mass balance assessment was performed to follow folate losses and gains. Folate production was observed during the soaking of pearl-millet grains (+26% to +79%), but the folate content of sieved batters (2.5 to 3.4μg/100g fresh weight) was drastically lower than that of milled soaked grains (17.3 to 19.4μg/100g FW). The final folate content of the porridges was very low (1.5 to 2.4μg/100g FW). The fermentation had no significant impact on folate content, whatever the duration and the process used. This study led to a better understanding of the impact on folate of the different processing steps involved in the preparation of ben-saalga.

Rice Bran Extract Reduces the Risk of Atherosclerosis in Post-Menopausal Vietnamese Women

We investigated whether pre-germinated brown rice bran extract containing acylated steryl glucosides (PSG) reduces the risk of atherosclerosis in post-menopausal Vietnamese women. A total of 60 post-menopausal Vietnamese women (45-65 y old) with high LDL cholesterol levels (over 140 mg/dL) were randomly divided into PSG (n=30) and placebo (n=30) groups. The subjects in the PSG group were assigned a daily intake of 6 capsules containing 50 mg PSG, and the subjects in the placebo group were assigned a daily intake of 6 capsules containing corn oil for 6 mo. Before baseline and after month 2, month 4, and month 6 of the intervention, we conducted anthropometric measurements, blood biochemical examinations, a nutrition survey, and physical activity, flow-mediated dilation (FMD), and cardio-ankle vascular index (CAVI) measurements. Serum LDL cholesterol concentrations were significantly reduced from 163.6±25.3 (mg/dL) to 135.9±26.8 (mg/dL) compared to the placebo group (p<0.001). FMD values of the placebo group were significantly reduced from 6.6±5.1 (%) to 4.7±2.6 (%) compared to the PSG group (p<0.05). Tumor necrosis factor (TNF)-α concentrations in the PSG group were significantly reduced from 19.8±11 (pg/mL) to 10.6±5.5 (pg/mL) compared to the placebo group (p<0.05). The findings suggest that PSG may improve LDL cholesterol, TNF-α levels, and FMD values. PSG might be considered in reducing the risk of atherosclerosis in post-menopausal Vietnamese women with high LDL cholesterol.

Potential Bioactive Compounds from Seaweed for Diabetes Management

Diabetes mellitus is a group of metabolic disorders of the endocrine system characterised by hyperglycaemia. Type II diabetes mellitus (T2DM) constitutes the majority of diabetes cases around the world and are due to unhealthy diet, sedentary lifestyle, as well as rise of obesity in the population, which warrants the search for new preventive and treatment strategies. Improved comprehension of T2DM pathophysiology provided various new agents and approaches against T2DM including via nutritional and lifestyle interventions. Seaweeds are rich in dietary fibres, unsaturated fatty acids, and polyphenolic compounds. Many of these seaweed compositions have been reported to be beneficial to human health including in managing diabetes. In this review, we discussed the diversity of seaweed composition and bioactive compounds which are potentially useful in preventing or managing T2DM by targeting various pharmacologically relevant routes including inhibition of enzymes such as α-glucosidase, α-amylase, lipase, aldose reductase, protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl-peptidase-4 (DPP-4). Other mechanisms of action identified, such as anti-inflammatory, induction of hepatic antioxidant enzymes’ activities, stimulation of glucose transport and incretin hormones release, as well as β-cell cytoprotection, were also discussed by taking into consideration numerous in vitro, in vivo, and human studies involving seaweed and seaweed-derived agents.

Plasma alkylresorcinols, biomarkers of whole-grain intake, are not associated with progression of coronary artery atherosclerosis in postmenopausal women with coronary artery disease

Objective

The objective of the present study was to examine the relationship between plasma alkyresorcinol (AR) concentrations, which are biomarkers of whole-grain intake, and atherosclerotic progression over 3 years in postmenopausal women with coronary artery disease.

Design

Plasma AR concentrations were measured by a validated GC–MS method in fasting plasma samples. Atherosclerosis progression was assessed using change in mean minimal coronary artery diameter (MCAD) and percentage diameter stenosis (%ST), based on mean proximal vessel diameter across up to ten coronary segments. Dietary intake was estimated using a 126-item interviewer-administered FFQ.

Setting

A prospective study of postmenopausal women participating in the Estrogen Replacement and Atherosclerosis trial.

Subjects

For the analysis of plasma AR concentrations and atherosclerotic progression, plasma samples and follow-up data on angiography were available for 182 women.

Results

Mean whole-grain intake was 9·6 (se 0·6) servings per week. After multivariate adjustment, no significant associations were observed between plasma AR concentrations and change in mean MCAD or progression of %ST. Plasma AR concentrations were significantly correlated with dietary whole grains (r=0·35, P<0·001), cereal fibre (r=0·33, P<0·001), bran (r=0·15, P=0·05), total fibre (r=0·22, P=0·003) and legume fibre (r=0·15, P=0·04), but not refined grains, fruit fibre or vegetable fibre.

Conclusions

Plasma AR concentrations were not significantly associated with coronary artery progression over a 3-year period in postmenopausal women with coronary artery disease. A moderate association was observed between plasma AR concentrations and dietary whole grains and cereal fibre, suggesting it may be a useful biomarker in observational studies.

Structural and physico-chemical properties of insoluble rice bran fiber: effect of acid–base induced modifications

Various acid–base regimes induced structural and physicochemical modifications of IRBF.

The health benefits of whole grains and fibre

Purpose

– The purpose of this paper is to evaluate the latest mounting evidence reporting associations between the important role of whole grains and fibre in lowering the risk of chronic diseases and health.

Design/methodology/approach

– A general systematic review was conducted to locate and summarise up-to-date published studies within the field. A Medline search identified human-controlled trials and observational studies published in the past five years.

Findings

– A total of 49 studies were identified. In observational studies, higher intakes of whole grain and dietary fibre were associated with a significantly lower risk of cardiovascular disease, diabetes, abdominal adiposity and certain cancers. This was further supported by human intervention trials, which reported benefits for appetite control, blood lipid levels, glycaemic control, digestive health and secondary cancer prevention. Mechanisms may relate to the micronutrients and phytonutrients present in high fibre foods.

Practical implications

– Practical advice is needed to help people identify foods rich in whole grains, e.g. breakfast cereals. UK fibre recommendations should be aligned with European guidelines and food labelling regulations, and a whole grain dietary recommendation, e.g. similar to the US guideline of three portions a day, could be introduced. Government and industry should play a role in communicating dietary fibre guidelines and the health benefits associated with whole grain and fibre, particularly insoluble fibre.

Originality/value

– This paper develops knowledge about whole grains, health and the importance of establishing whole-grain dietary recommendations.

Whole grains and pulses: a comparison of the nutritional and health benefits

Nutrition plays an important role in the prevention and management of disease. Whole grain cereals contain a host of nutrients and bioactive substances that have health-promoting effects. Epidemiological evidence shows a consistent inverse association between whole grain intake and the risk of chronic disease. Despite a concerted effort by scientists, educators, and policy makers to promote the consumption of whole grains, it remains dismally short of the recommended intakes. Pulses (dried beans and peas) differ from whole grains in their structural and physicochemical properties and have varying amounts of fiber, resistant starch, vitamins, minerals, and other bioactive components; nevertheless, these food groups complement each other. Observational as well as intervention trials show that pulse consumption has beneficial effects on the prevention and management of chronic disease. The nutritional and phytochemical components of pulses coupled with those of whole grains suggest a potential synergistic effect that could provide significant health benefits.

Mediterranean diet and carotid atherosclerosis in the Northern Manhattan Study

OBJECTIVE

Adherence to a Mediterranean-style diet (MeDi) may protect against clinical vascular events by reducing atherosclerosis, but data is limited. This is the first observational study of the association between MeDi adherence and carotid plaque thickness and area.

METHODS

The study included 1374 participants of the population-based Northern Manhattan Study with diet assessed and carotid intima-media thickness (cIMT) and plaque measured using B-mode ultrasound (mean age 66 ± 9 years, 60% female, 60% Hispanic, 18% White, 19% Black). A MeDi adherence score (range = 0-9, 9 representing maximal adherence) was examined continuously and in quintiles (3/4/5/6-9 vs. 0-2).

RESULTS

Mean cIMT = 0.9 ± 0.1 mm and 57% had plaque (median plaque thickness = 1.5 mm, 75th percentile = 2.2; median plaque area = 4.2 mm(2), 75th percentile = 15.8). There was no association between MeDi and cIMT or plaque presence. MeDi adherence was inversely associated with the 75th percentile of plaque thickness and median of plaque area in quantile regression analyses. These associations persisted after controlling for demographics, smoking, physical activity, and total energy consumption (effect of a 1-point increase in MeDi score on the 75th percentile of plaque thickness = -0.049 mm, p = 0.03; median of plaque area = -0.371 mm(2), p = 0.03), and when additionally controlling for vascular disease biomarkers, medication use, BMI, and previous cardiac disease. The protective associations appeared strongest for those with a MeDi score of 5 (4th quintile) vs. 0-2 (bottom quintile). Differential effects of a MeDi on plaque thickness and area across race/ethnic groups was suggested.

CONCLUSIONS

Moderate and strict adherence to a MeDi may protect against a higher burden of carotid atherosclerotic plaque, which may mediate the protection against clinical vascular events. Efforts to improve adherence to a MeDi are critical to reducing the burden of atherosclerotic disease.

The association between carotid intima media thickness and individual dietary components and patterns

AIMS

To review: 1) the correlation between individual dietary components and carotid intima media thickness (cIMT); 2) the relationship between dietary patterns and cIMT; 3) the effect of dietary interventions on cIMT progression.

DATA SYNTHESIS

An electronic search for epidemiological and intervention trials investigating the association between dietary components or patterns of intake and cIMT was performed in PUBMED, EMBASE and the Cochrane Library. Epidemiological data shows that a higher intake of fruit, wholegrains and soluble fibre and lower consumption of saturated fat in favour of polyunsaturated fat is associated with lower cIMT. In people at high risk of cardiovascular disease >93 g/day of fruit is associated with lower cIMT. Lower cIMT has also been observed when >0.79 serves/day of wholegrains and >25 g/day of fibre, predominately in the soluble form is consumed. Saturated fat is positively associated with cIMT, for every 10 g/day increase in saturated fat cIMT is 0.03 mm greater. Olive oil is inversely associated with cIMT, with a benefit seen when >34 g/day is consumed. While there are many epidemiological studies exploring the association between dietary intake and cIMT there are few intervention studies. Intervention studies show that a Mediterranean diet may reduce cIMT progression, especially in those with a higher cIMT.

CONCLUSIONS

A Mediterranean style dietary pattern, which is high in fruits, wholegrains, fibre and olive oil and low in saturated fat, may reduce carotid atherosclerosis development and progression. However further research from randomised controlled trials is required to understand the association between diet and cIMT and the underlying mechanisms.

Adherence to the USDA dietary recommendations for fruit and vegetable intake and risk of fatal stroke among ethnic groups: a prospective cohort study

BACKGROUND

Stroke is the fourth leading cause of death in the U.S. and stroke mortality rates differ substantially by ethnic group. The impact of adherence to the USDA dietary guidelines on risk for fatal stroke among different ethnic groups has not previously been examined.

METHODS

A prospective cohort design was used to examine associations between adherence with dietary recommendations for fruit and vegetable intake and risk for stroke mortality among 174,888 men and women representing five ethnic groups; African American, Native Hawaiian, Japanese American, Latino, and Caucasian. Dietary intake was assessed using a mailed quantitative food frequency questionnaire. Associations were examined using Cox proportional hazards models.

RESULTS

There was no evidence that ethnicity modified associations between fruit and vegetable intake and stroke mortality. When data for different ethnicities were combined, a reduced risk for fatal stroke was observed among women who were adherent with the USDA dietary recommendations for vegetable intake, although this result did not reach statistical significance (RR = 0.84, 95% CI = 0.68-1.04). No associations were observed among men.

CONCLUSIONS

The results of this study do not provide evidence that dietary intake of fruits and vegetables differentially impacts risk for stroke mortality among different ethnic groups.

Milk-derived peptides, Val-Pro-Pro and Ile-Pro-Pro, attenuate atherosclerosis development in apolipoprotein e-deficient mice: a preliminary study

Milk-derived peptides, Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP), have angiotensin I-converting enzyme inhibitory activities and blood pressure-lowering effects. We examined the effects of these peptides on the development of atherosclerosis in apolipoprotein E-deficient [apoE(-/-)] mice. For 31 weeks, six-week-old male apoE(-/-) mice received a diet that included one of the following: fermented milk containing both VPP and IPP; casein hydrolysate containing both of these peptides; synthesized VPP; synthesized IPP; enalapril; captopril; or control diet. At the end of feeding, blood biochemistry, aortic atherogenesis, and gene expression by DNA microarray analysis were evaluated. There were no significant changes in the plasma lipid levels and 8-isoprostane, a marker of oxidative stress. The area ratio of intima to media in the aortic arch was significantly lower in the fermented milk, casein hydrolysate, synthesized VPP, enalapril, and captopril groups than in the control group. As is common with diets containing VPP and/or IPP, we observed reductions in mRNA expression of inflammatory cytokines, such as interleukin (IL)-6 and IL-1β, oxidized low-density lipoprotein receptor, and transcription regulators. These results suggest that a continuous intake of VPP and IPP might be beneficial for preventing atherosclerosis caused by hypercholesterolemia.

The effect of dietary fibre on reducing the glycaemic index of bread

As bread is the most relevant source of available carbohydrates in the diet and as lowering dietary glycaemic index (GI) is considered favourable to health, many studies have been carried out in order to decrease the GI of bread. The most relevant strategy that has been applied so far is the addition of fibre-rich flours or pure dietary fibre. However, the effectiveness of dietary fibre in bread in reducing the GI is controversial. The purpose of the present review was to discuss critically the effects obtained by adding different kinds of fibre to bread in order to modulate its glycaemic response. The studies were selected because they analysed in vivo whether or not dietary fibre, naturally present or added during bread making, could improve the glucose response. The reviewed literature suggests that the presence of intact structures not accessible to human amylases, as well as a reduced pH that may delay gastric emptying or create a barrier to starch digestion, seems to be more effective than dietary fibre per se in improving glucose metabolism, irrespective of the type of cereal. Moreover, the incorporation of technologically extracted cereal fibre fractions, the addition of fractions from legumes or of specifically developed viscous or non-viscous fibres also constitute effective strategies. However, when fibres or wholemeal is included in bread making to affect the glycaemic response, the manufacturing protocol needs to reconsider several technological parameters in order to obtain high-quality and consumer-acceptable breads.

Whole grain wheat sourdough bread does not affect plasminogen activator inhibitor-1 in adults with normal or impaired carbohydrate metabolism

BACKGROUND AND AIMS

Epidemiological studies suggest whole grain consumption is associated with a reduced risk of cardiovascular disease (CVD), possibly through alterations in glucose metabolism and subsequent effects on plasminogen activator inhibitor (PAI)-1, a novel biomarker for CVD. Our aim was to investigate the effect of 6 wk of whole grain wheat sourdough bread consumption versus refined white bread on PAI-1.

METHODS AND RESULTS

Normoglycemic/normoinsulinemic (NGI; n = 14; age 53 ± 6 y; BMI 26.5 ± 2.9 kg/m(2)) and hyperglycemic/hyperinsulinemic (HGI; n = 14; age 57 ± 7 y; BMI 35.7 ± 5.7 kg/m(2)) adults incorporated whole grain wheat sourdough (162.5 g) or white (168.8 g) bread into their diet, for 6 wk in a randomized crossover study. Pre- and post-intervention, fasting blood samples were analyzed for PAI-1 (primary outcome), as well as glucose, insulin and glucagon (secondary outcomes) at fasting and postprandially after an oral glucose tolerance test (OGTT). Anthropometric measures, fasting glucose, insulin, glucagon and PAI-1 antigen and activity were not different between treatments in either NGI or HGI adults. Glucose incremental area under the curve (iAUC) was lower (19%, P = 0.02) after 6 wk consumption of whole grain wheat sourdough bread compared to white bread in the HGI group, with no differences in insulin or glucagon iAUC in either group.

CONCLUSION

Our data showed decreased glucose iAUC after an OGTT following 6 wk whole grain wheat bread consumption in adults with differing glycemic/insulinemic status, but no improvements in PAI-1 or fasting glycemic parameters.

Whole grains: benefits and challenges

Inclusion of whole grains (WG) in the diet is recommended in dietary guidance around the world because of their associations with increased health and reduced risk of chronic disease. WGs are linked to reduced risk of obesity or weight gain; reduced risk of cardiovascular disease (CVD), including coronary heart disease (CHD), hypertension, and stroke; improved gut health and decreased risk of cancers of the upper gut; perhaps reduced risk of colorectal cancer; and lower mortality rate. The 2005 United States Dietary Guidelines Advisory Committee has recommended that consumers make "half their grains whole." Yet, whole grains are puzzling both consumers and scientists. Scientists are trying to determine whether their health benefits are due to the synergy of WG components, individual WG components, or the fact that WG eaters make many of the recommended diet and lifestyle choices. Consumers need to understand the WG benefits and how to identify WG foods to have incentive to purchase and use such foods. Industry needs to develop great-tasting, clearly-labeled products. With both these factors working together, it will be possible to change WG consumption habits among consumers.

Foods for the prevention of diabetes: how do they work?

With the diabetes epidemic reaching menacing proportions worldwide, there is an urgent need for the development of cost-efficient prevention strategies to be effective at the population level. Great potential in this direction lies in properly designed, large-scale dietary interventions. The macronutrient composition and the caloric content of our diet are major determinants of glucose homeostasis and there is a continuously growing list of foods, nutrients or individual compounds that have been associated with an increased or reduced incidence of diabetes mellitus. These include fat, carbohydrates, fibre, alcohol, polyphenols and other micronutrients or individual dietary compounds, which have been shown to either promote or prevent a progression towards a (pre-)diabetic state. This review aims to briefly summarize relevant epidemiological data linking foods to diabetes and to provide insights into the mechanisms through which these effects are mediated. These include improvement of insulin sensitivity or promotion of insulin resistance, regulation of inflammatory pathways, regulation of glucose transport and tissue glucose uptake, aggravation or attenuation of postprandial glycaemia/insulinaemia, interactions with hormonal responses and β-cell-dependent mechanisms.

Putting the whole grain puzzle together: health benefits associated with whole grains--summary of American Society for Nutrition 2010 Satellite Symposium

The symposium "Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains" sponsored by the ASN brought together researchers to review the evidence regarding the health benefits associated with whole grains. Current scientific evidence indicates that whole grains play an important role in lowering the risk of chronic diseases, such as coronary heart disease, diabetes, and cancer, and also contribute to body weight management and gastrointestinal health. The essential macro- and micronutrients, along with the phytonutrients present in whole grains, synergistically contribute to their beneficial effects. Current evidence lends credence to the recommendations to incorporate whole grain foods into a healthy diet and lifestyle program. The symposium also highlighted the need for further research to examine the role of whole grain foods in disease prevention and management to gain a better understanding of their mechanisms of action.

Association between meat consumption and carotid intima-media thickness in Korean adults with metabolic syndrome

OBJECTIVES

The effect of meat consumption on cardiometabolic risk has been continuously studied, but their associations are not conclusive. The aim of this study is to examine the association between the consumption of meat or red meat and carotid intima-media thickness (IMT) in healthy Korean adults.

METHODS

This study evaluated 2374 community-dwelling adults (933 men and 1441 women) who were free of cardiovascular disease or cancer, living in a rural area in Korea. Total meat and red meat intakes were assessed with a validated 103 item-food frequency questionnaire. Carotid IMT was evaluated ultrasonographically, IMTmax was defined as the highest value among IMT of bilateral common carotid arteries.

RESULTS

After adjustment for potential confounding factors, the mean IMTmax tended to increase in higher meat consumption groups in both men and women with metabolic syndrome (p for trend= 0.027 and 0.049, respectively), but not in participants without metabolic syndrome. Frequent meat consumption (≥5 servings/week) was significantly associated with higher IMTmax in men with metabolic syndrome (by 0.08 mm, p=0.015). Whereas, the association was not significant in women (by 0.05 mm, p=0.115). Similar but attenuated findings were shown with red meat intake.

CONCLUSIONS

Our findings suggest that a higher meat consumption may be associated with a higher carotid IMT in Korean adults with metabolic syndrome. The frequent meat consumption (≥5 servings/week), compared with the others, was associated with a higher carotid IMTmax only in men with metabolic syndrome. Further research is required to explore optimal meat consumption in people with specific medical conditions.

Whole-grain consumption is associated with diet quality and nutrient intake in adults: the National Health and Nutrition Examination Survey, 1999-2004

BACKGROUND

The consumption of whole grains and its association with nutrient intake has not been assessed in a recent nationally representative population.

OBJECTIVE

To examine the association of consumption of whole grains, using the new whole-grain definition, with diet quality and nutrient intake in a recent, nationally representative sample of adults.

DESIGN

Secondary analysis of cross-sectional data from 1999-2004 National Health and Nutrition Examination Survey.

PARTICIPANTS AND METHODS

Adults aged 19 to 50 years (n=7,039) and aged 51 years and older (n=6,237).

MAIN OUTCOME MEASURES

Participants were divided into four whole-grain consumption groups: ≤0 to <0.6, ≥0.6 to <1.5, ≥1.5 to <3.0, and ≥3.0 servings (ounce equivalents)/day. Macro- and micronutrient intakes and diet quality, using the Healthy Eating Index, were determined for each group.

STATISTICAL ANALYSES

Sample weights were applied. The percentages of adults in whole-grain consumption groups were calculated. The covariates used were energy, ethnicity, sex, and age. Least-square means were calculated. P for linear trend analysis was determined using whole-grain intake as a linear covariate. A P value of ≤0.05 was considered significant.

RESULTS

Adults aged 19 to 50 and 51+ years consumed a mean of 0.63 and 0.77 servings of whole grains per day, respectively. For both age groups, diet quality and intake of energy, fiber, and polyunsaturated fatty acids were significantly higher in those consuming the most servings of whole grains. Intake of total sugars (19 to 50 year age group only), added sugars, saturated fatty acids, monounsaturated fatty acids, and cholesterol was significantly lower in those consuming the most servings of whole grains. Intake of all micronutrients, except vitamin B-12 and sodium, was higher among individuals who consumed the most servings of whole grains.

CONCLUSIONS

Overall consumption of whole grains in the US population was low using the recently updated whole-grain definition. Adults who consumed the most servings of whole grains had better diet quality and nutrient intakes.

The effect of whole grain wheat sourdough bread consumption on serum lipids in healthy normoglycemic/normoinsulinemic and hyperglycemic/hyperinsulinemic adults depends on presence of the APOE E3/E3 genotype: a randomized controlled trial

Background

Epidemiological studies associate consumption of whole grain foods, including breads, with reduced cardiovascular disease (CVD) risk; however, few studies have compared wheat whole grains with wheat refined grains.

Methods

This study investigated effects of 6-week consumption of whole grain wheat sourdough bread in comparison to white bread on fasting serum lipids in normoglycemic/normoinsulinemic (NGI; n = 14) and hyperglycemic/hyperinsulinemic (HGI; n = 14) adults. The influence of single-nucleotide polymorphisms, 3 within the APOE gene (E2, E3, E4) and 2 within the hepatic lipase gene promoter (LIPC -514C>T, LIPC -250G>A) were considered.

Results

At baseline, HGI participants had significantly higher body weight, waist circumference, body fat, and fasted glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), glucagon, triacylglycerols (TAG) and TAG:HDL-cholesterol, compared to NGI participants; however, none of these in addition to none of the other serum lipids, differed between bread treatments, within either participant group. For participants with the APOE E3/E3 genotype, LDL-cholesterol (P = 0.02) increased in the NGI group (n = 7), and TAG (P = 0.03) and TAG:HDL-cholesterol (P = 0.04) increased in the HGI group (n = 10), following consumption of whole grain wheat sourdough compared to white bread.

Conclusions

In summary, 6-week consumption of whole grain wheat sourdough bread did not significantly modulate serum lipids in NGI or HGI adults; however, it significantly increased LDL-cholesterol, TAG and TAG:HDL-cholesterol in participants with the APOE E3/E3 genotype. These data add to limited literature comparing wheat whole grains to wheat refined grains on CVD risk and highlight the need to consider genetic variation in relation to lipoprotein lipid content and CVD risk.

Food intake patterns associated with carotid artery atherosclerosis in the Insulin Resistance Atherosclerosis Study

We aimed to identify food intake patterns that operate via haemostatic and inflammatory pathways on progression of atherosclerosis among 802 middle-aged adults with baseline and 5-year follow-up ultrasound measurements of common (CCA) and internal carotid artery (ICA) intimal medial thickness (IMT). Food intake was ascertained with an FFQ. We derived food patterns using reduced rank regression (RRR) with plasminogen activator inhibitor 1 and fibrinogen as response variables. We explored the impact of various food pattern simplification approaches. We identified a food pattern characterised by higher intakes of less healthful foods (low-fibre bread and cereal, red and processed meat, cottage cheese, tomato foods, regular soft drinks and sweetened beverages) and lower intakes of more healthful foods (wine, rice and pasta, meal replacements and poultry). The pattern was positively associated with mean CCA IMT at follow-up (P = 0.0032), a 1 sd increase corresponding to an increase of 13 mum higher CCA IMT at follow-up, adjusted for demographic and cardiovascular risk factors. With increasing pattern quartile (Q), the percentage change in CCA IMT increased significantly: Q1 0.8 %; Q2 3.2 %; Q3 8.6 %; Q4 7.9 % (P = 0.0045). No clear association with ICA IMT was observed. All simplification methods yielded similar results. The present results support the contention that a pro-inflammatory and pro-thrombotic dietary pattern increases the rate of coronary artery atherosclerosis progression, independent of traditional cardiovascular risk factors. RRR is a promising and robust tool for moving beyond the previous focus on nutrients or foods into research on the health effects of broader dietary patterns.

Children's acceptance, nutritional, and instrumental evaluations of whole grain and soluble fiber enriched foods

The Dietary Guidelines for Americans 2005 report recommends 3 or more daily ounce-equivalents of whole grains (WG), and the FDA suggests consumption of 25 g of total dietary fiber (TDF) and 6 g of soluble fiber (SF) for a 2000-calorie diet. Efforts to increase the consumption of WG and SF among elementary school-aged children are needed. The objectives of this study were to examine the consumption of WG- and SF-enriched burritos and cookies among elementary school-aged children and to perform a quality evaluation of all products. Children in grades K to 6 from a local elementary school consumed control (CTR) products made with refined flour along with the test products (TRT) over a 13-wk period. TRT burritos and cookies contained 51% and 100% WG, respectively. CTR and TRT products were served on 3 and 4 different Fridays, respectively. Children's consumption was determined via plate waste. Quality parameters such as texture, color, water activity, weight, and product dimensions were also measured. No significant differences in consumption between CTR and TRT burritos and cookies were found (36% and 90%, respectively). Texture (area) was higher for CTR burritos compared with TRT burritos (1.31 and 0.66 kg-s, respectively). CTR burritos were lighter than TRT burritos with L* values of 80.04 and 64.61, respectively. CTR cookies required a higher breaking force (3.14 compared with 0.58 kg), were lighter than TRT cookies (63.18 compared with 50.27), and had lower water activity (0.5 compared with 0.71).

Functional food for pregnant, lactating women and in perinatal nutrition: a role for dietary fibres?

PURPOSE OF REVIEW

If the benefits of dietary fibre in healthy adults have extensively been studied, little information is available on the specific needs of pregnant, lactating women or foetus. As far as infants are concerned, milk oligosaccharides are supposed to be the optimal 'dietary fibre'. The supplementation of infant formula with prebiotic oligosaccharides is still discussed. However, recent studies provide a large amount of information, allowing a new discussion on this topic.

RECENT FINDINGS

Most recent findings are linked to the involvement of dietary fibre in occurrence or prevention of obesity. The multiple mechanisms appear more clearly than earlier. This finding will soon allow appropriate counselling for young mothers at risk of obesity and/or postpartum retention weight, gestational diabetes and preeclampsia. Another area which benefits from recent research is the use of prebiotics in formula.

SUMMARY

Pregnancy is a critical period during which many physiologic changes occurred and is associated with several gut disorders and metabolic diseases. Dietary fibre may be helpful in the prevention and management of these diseases. Lactation and pregnancy are two phases during which food consumption of the mother can interact with the physiology of the baby. Moreover, the use of formula supplemented in oligosaccharides is able to compensate for the lack of some of the complex molecules naturally present in human milk.

Adherence to 2005 Dietary Guidelines for Americans is associated with a reduced progression of coronary artery atherosclerosis in women with established coronary artery disease

BACKGROUND

A premise of the 2005 Dietary Guidelines for Americans (DGA) is chronic disease prevention.

OBJECTIVE

The goal was to determine whether a diet meeting the DGA is associated with less atherosclerotic lesion progression.

DESIGN

We used the data from 224 postmenopausal women with established coronary artery disease enrolled in the Estrogen Replacement and Atherosclerosis Study. Atherosclerosis progression was defined by repeated measures of quantitative angiography over a 3-y period. Adherence to the key DGA recommendations was measured by using the DGA Adherence Index (DGAI; possible range: 0-20), with each component weighted equally, and the modified DGAI score (wDGAI; possible range: -0.19-0.51), with each component weighted based on its relation to atherosclerosis progression. Mixed-model regression analyses were performed to assess the association between diet and atherosclerosis progression.

RESULTS

No women consumed a diet meeting all of the DGA recommendations. The mean (range) of the DGAI score was 14.1 (8.0-19.0). DGAI was not associated with atherosclerosis progression (P = 0.44), whereas wDGAI was inversely associated; a 1-SD difference in wDGAI was related to 0.049-mm less narrowing of the coronary arteries (SE = 0.017, P = 0.004).

CONCLUSIONS

In postmenopausal women with established heart disease, under the assumption that all DGA recommendations are similarly effective, overall adherence was not associated with atherosclerosis progression. However, assigning differential weights to the DGA recommendations, the adherence was significantly associated with slower atherosclerosis progression. Assuming equity of associations between all dietary recommendations and disease outcomes is a limitation in accurately examining the effectiveness of the DGA.

Glucose and insulin responses to whole grain breakfasts varying in soluble fiber, beta-glucan: a dose response study in obese women with increased risk for insulin resistance

BACKGROUND

A high intake of whole grains containing soluble fiber has been shown to lower glucose and insulin responses in overweight humans and humans with type 2 diabetes.

AIM OF THE STUDY

We investigated the linearity of this response after consumption of 5 breakfast cereal test meals containing wheat and/or barley to provide varying amounts of soluble fiber, beta-glucan (0, 2.5, 5, 7.5 and 10 g).

METHODS

Seventeen normoglycemic, obese women at increased risk for insulin resistance consumed 5 test meals within a randomized cross-over design after consuming controlled diets for 2 days. Blood samples for glucose and insulin response were obtained prior to and 30, 60, 120 and 180 min after consuming the test meals.

RESULTS

Consumption of 10 g of beta-glucan significantly reduced peak glucose response at 30 min and delayed the rate of glucose response. Area under the curve for 2 h-postprandial glycemic response was not affected by beta-glucan content. However, peak and area under the curve of insulin responses were significantly affected by the beta-glucan amount in an inverse linear relationship.

CONCLUSION

These data suggest that acute consumption of 10 g of beta-glucan is able to induce physiologically beneficial effects on postprandial insulin responses in obese women at risk for insulin resistance.

Grain foods and health: a primer for clinicians

Preventing many chronic diseases in North America requires substantial changes in dietary habits. Achieving a better balance of grain-based foods through the inclusion of whole grains is one scientifically supported dietary recommendation. Epidemiological and other types of research continue to document health benefits for diverse populations who have adequate intakes of both folic acid-fortified grain foods and whole grains. Folic acid fortification of grains is associated with reduced incidence of neural tube and other birth defects and may be related to decreased risk of other chronic disease. Whole grain intake is associated with reduced risk of chronic disease. Specifically, there is a decreased risk of obesity, coronary heart disease, hypertension, stroke, metabolic syndrome, type 2 diabetes, and some cancers observed among the highest whole grain eaters compared with those eating little or no whole grains. Nationally promulgated dietary recommendations such as those in the US Dietary Guidelines or by health promotion organizations such as the American Heart Association have incorporated the science on whole grains, recommending that consumers increase their whole grain intake. The US Dietary Guidelines state that consumers select half of the recommended bread and cereal servings as whole grain. Thus, the recommendations recognize the importance of adequate folic acid intake from refined, fortified grains to reduce the risk of birth defects and other disorders and to reflect the existing science on whole grains. The association between whole grains and decreased chronic disease is not surprising because whole grains are a source of vitamins, minerals, fatty acids, anti oxidants, and other phytochemicals and dietary fiber. Each of these components can act singly or in tandem to contribute to specific health-maintaining and disease-preventing mechanisms. Health professionals should be aware of these benefits and advocate these dietary strategies to help prevent chronic disease and to improve overall health.

KEYWORDS

nutrition; whole grain; folic acid; disease prevention; diet; mortality; diabetes; cereal; pseudocereal; phytochemicals; anti-oxidants.

Urinary 3-(3,5-dihydroxyphenyl)-1-propanoic acid, an alkylresorcinol metabolite, is a potential biomarker of whole-grain intake in a U.S. population

5-n-Alkylresorcinols (AR) are a major group of phenolic compounds in whole-grain wheat, rye, and barley. As such, they may serve as potential biomarkers of whole-grain intake, because they are quantifiable intact in plasma and as metabolites in urine. We examined relationships between 12-h urinary excretion of AR metabolite 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA) and self-reported habitual intake of whole-grain foods measured by 3-d food record (3DFR) and FFQ. Urine samples from 100 men and women were analyzed for DHPPA using HPLC with coularray detection. DHPPA excretion ranged from 1.3 to 99.4 (mean +/- SE, 14.0 +/- 1.5) mumol/12 h. Whole-grain food intake, as determined by 3DFR and FFQ and adjusted for BMI and energy and fiber intake, was significantly associated with 12-h urinary DHPPA excretion. Based on 3DFR, whole-grain wheat + rye consumers had a 44% higher DHPPA excretion than nonconsumers [ratio of excretion (95% CI) = 1.44 (1.04, 1.97); P = 0.029]. Using whole-grain intake estimated by FFQ, a serving increase in whole-grain wheat + rye intake increased DHPPA excretion by 94% [ratio of excretion (95% CI) = 1.94 (1.35, 2.78); P = 0.001] and a serving increase in whole grains as defined more broadly in epidemiologic studies of whole-grain intake and disease risk (whole-grain wheat, rye, oats, and corn) increased DHPPA by 67% [ratio of excretion (95% CI) = 1.67 (1.28, 2.17); P < 0.0001]. This study supports the potential utility of urinary DHPPA as a biomarker of whole-grain intake in a U.S. population.