Nutritional Quality of Legumes, and Their Role in Cardiometabolic Risk Prevention: A Review

Effects of short- and long-term Mediterranean-based dietary treatment on plasma LC-QTOF/MS metabolic profiling of subjects with metabolic syndrome features: The Metabolic Syndrome Reduction in Navarra (RESMENA) randomized controlled trial

SCOPE

Adherence to the Mediterranean diet has been associated with a reduced risk of metabolic syndrome (MetS). Metabolomics approach may contribute to identify beneficial associations of metabolic changes affected by Mediterranean diet-based interventions with inflammatory and oxidative-stress markers related to the etiology and development of the MetS.

METHODS AND RESULTS

Liquid chromatography coupled to quadrupole-time of flight-MS metabolic profiling was applied to plasma from a 6-month randomized intervention with two sequential periods, a 2-month nutritional-learning intervention period, and a 4-month self-control period, with two energy-restricted diets; the RESMENA diet (based on the Mediterranean dietary pattern) and the Control diet (based on the American Heart Association guidelines), in 72 subjects with a high BMI and at least two features of MetS. The major contributing biomarkers of each sequential period were lipids, mainly phospholipids and lysophospholipids. Dependency network analysis showed a different pattern of associations between metabolic changes and clinical variables after 2 and 6 month of intervention, with a highly interconnected network during the nutritional-learning intervention period of the study.

CONCLUSION

The 2-month RESMENA diet produced significant changes in the plasma metabolic profile of subjects with MetS features. However, at the end of the 6-month study, most of the associations between metabolic and clinical variables disappeared; suggesting that adherence to healthy dietary habits had declined during the self-control period.

Valorization of traditional foods: nutritional and bioactive properties of Cicer arietinum L. and Lathyrus sativus L. pulses

BACKGROUND

The use of traditional foods can enrich our diet, perpetuating important elements of local knowledge and cultural inheritance. Raw, soaked and cooked samples of two Fabaceae species (Cicer arietinum L. and Lathyrus sativus L.) were characterized regarding nutritional and bioactive properties.

RESULTS

L. sativus gave the highest carbohydrate, protein, ash, saturated fatty acid and polyunsaturated fatty acid content, and lowest fat and energy value. Furthermore, it also showed the highest concentration of flavonoids and antioxidant activity. Cicer arietinum gave the highest concentration of sugars, organic acids and tocopherols. The soaking process did not significantly affect macronutrients, but cooking (boiling) decreased protein, ash, sugars and organic acids, and increased carbohydrates, fat, tocopherols, bioactive compounds and antioxidant activity. No differences were obtained for fatty acid composition.

CONCLUSION

The present study highlights the nutritional profile and bioactive properties of these agricultural varieties of C. arietinum and L. sativus pulses, and valorizes their traditional consumption and the use in modern diets.

Dietary phytochemical index is inversely associated with the occurrence of hypertension in adults: a 3-year follow-up (the Tehran Lipid and Glucose Study)

BACKGROUND/OBJECTIVE

The epidemiological association of phytochemical-rich foods with the risk of hypertension is unclear. This study aimed to determine the association of dietary phytochemical index (PI) with the occurrence of hypertension (HTN) after 3 years of follow-up in Tehranian adults.

SUBJECTS/METHODS

This prospective study was conducted on 1546 nonhypertensive subjects, aged 20-70 years. Dietary intake was collected by validated semiquantitative food frequency questionnaire (FFQ). Dietary PI was calculated as (dietary energy derived from phytochemical-rich foods (kcal)/total daily energy intake (kcal)) × 100. Blood pressure was measured at baseline and after 3 years of follow-up and HTN was defined by Joint National Committee on prevention, detection, evaluation and treatment of high blood pressure criteria. The odds of HTN after 3 years in each quartile category of dietary PI were estimated by logistic regression model and adjusted for potential variables.

RESULTS

The mean age of participants was 38.0±12.0 years and 43% were male. The mean dietary PI was 29.1±11.8. After 3 years of follow-up, 265 (17.1%) new cases of HTN were identified. No significant changes were observed in the systolic and diastolic blood pressure across quartile categories of dietary PI. After adjustment for confounders, the odds (95% confidence interval) of HTN across quartiles of dietary PI were 1.00, 0.97 (0.62-1.38), 0.69 (0.45-1.07) and 0.52 (0.32-0.84) (P for trend=0.004).

CONCLUSIONS

Consumption of phytochemical-rich foods may prevent the development of HTN. Further investigations are, however, recommended.

Substitution of red meat with legumes in the therapeutic lifestyle change diet based on dietary advice improves cardiometabolic risk factors in overweight type 2 diabetes patients: a cross-over randomized clinical trial

BACKGROUND/OBJECTIVE

The objective of this study was to determine the effects of substitution of red meat with legumes in the Therapeutic Lifestyle Change (TLC) diet on cardiometabolic risk factors in type 2 diabetes patients based on dietary education.

SUBJECTS/METHODS

This study was a randomized, controlled, cross-over trial. Thirty-one participants (24 women and 7 men; age: 58.1 ± 6.0 years) with type 2 diabetes were randomly assigned to consume a control diet (legume-free TLC diet) and legume-based TLC diet for 8 weeks. Legume-based TLC diet was the same as the control diet, but the legume-based TLC group was advised to replace two servings of red meat with legumes, 3 days per week. After the interventional period, a washout period was conducted for 4 weeks. The groups were then advised to follow the alternate treatment for 8 weeks. Cardiometabolic risk factors were measured.

RESULTS

Compared with the legume-free TLC diet, the legume-based TLC diet significantly decreased fasting blood glucose (P=0.04), fasting insulin (P=0.04), triglyceride concentrations (P=0.04) and low-density lipoprotein cholesterol (P=0.02). Total cholesterol concentrations decreased after consumption of both TLC diet and legume TLC diet; however, the data did not differ significantly between the two diets. body mass index (BMI), waist circumference, systolic and diastolic blood pressures did not change significantly after consumption of either the legume-free TLC diet or the legume-based TLC diet.

CONCLUSIONS

Dietary advice given for substitution of red meat with legume intakes within a TLC diet-improved lipid profiles and glycemic control among diabetes patients, which were independent from BMI change. This trial was registered in the Iranian Registry of Clinical Trials (http://www.irct.ir) as IRCT201202251640N7.

Cardiometabolic risk factors are associated with high urinary enterolactone concentration, independent of urinary enterodiol concentration and dietary fiber intake in adults

The study objective was to evaluate independent and interactive associations of dietary fiber intake and high urinary enterolignans with cardiometabolic risk factors. The analysis included 2260 adults (≥20 y of age) from the 2003-2010 NHANES. Logistic regression models were used to evaluate obesity and clinically defined cardiometabolic risk factors in relation to dietary fiber intake and urinary enterolignan concentrations. Three sets of models were created: 1) independent associations, 2) mutually adjusted associations, and 3) interactions. Models were adjusted for age, gender, race/ethnicity, education, smoking status, and energy intake. High concentrations were considered to be above the 90th percentile of urinary enterolignan concentrations. Increasing dietary fiber intake was associated with high blood pressure (P = 0.02) and low serum HDL cholesterol (P-trend = 0.03). High urinary enterodiol concentration was not associated with obesity or cardiometabolic risk factors. High urinary enterolactone concentration was inversely associated with obesity (OR: 0.44; 95% CI: 0.29, 0.66), abdominal obesity (OR: 0.58; 95% CI: 0.39, 0.87), high serum C-reactive protein (CRP; OR: 0.52; 95% CI: 0.37, 0.74), high serum triglycerides (OR: 0.39; 95% CI: 0.23, 0.61), low serum HDL cholesterol (OR: 0.37; 95% CI: 0.23, 0.61), and metabolic syndrome (OR: 0.47; 95% CI: 0.30, 0.74). In mutually adjusted models, enterolactone associations observed in independent models remained similar, but associations for dietary fiber intake were attenuated, with the exception of blood pressure. In interaction models, there were 2 significant interactions: between high urinary enterodiol concentration and dietary fiber intake for high serum CRP (P = 0.04) and high plasma glucose (P = 0.04). Overall, being in the highest 10% of urinary enterolactone concentration was associated with cardiometabolic risk factors, independent of dietary fiber intake and enterodiol concentration. Future studies are warranted to evaluate physiologic actions of enterolactone or aspects of the gut microbial profile responsible for lignan metabolism to enterolactone.

Inverse association of legume consumption and dyslipidemia: Isfahan Healthy Heart Program

BACKGROUND

Dietary intervention for improving serum lipids emphasizes on dietary fiber, plant protein, and flavonoids. This study was performed to examine whether regular legume consumption could alter serum lipids level and prevalence of dyslipidemia.

MATERIALS AND METHODS

This cross-sectional study was performed among 9660 randomly selected Iranian adults in 3 districts in the central part of Iran, using data collected in the Isfahan Healthy Heart Program in 2007. Dietary behavior including frequency of legume consumption was assessed by 48-item food frequency questionnaire. Fasting serum lipids were measured by standard enzymatic methods. We applied analysis covariance test to compare adjusted mean of serum lipids across legume consumption quartile and logistic regression test was used to determine odds ratio 95% confidence interval of dyslipidemia based on legume consumption in unadjusted and 4-adjusted models.

RESULTS

Adjusted mean triglyceride significantly reduced and high-density lipoprotein cholesterol (HDL-C) enhanced by increasing legume consumption (P = .04). The frequency of legume consumption associated with occurrence of all kinds of dyslipidemia except for hypercholesterolemia, especially for those who had consumed legume more than 1 time per day in adjusted models (hypertriglyceridemia: 0.82 [0.68-0.98]; high low-density lipoprotein [LDL-C]: 0.76 [0.60-0.97], and low HDL-C: 0.81 [0.71-0.92]).

CONCLUSION

We found an inverse dose-response association between the frequency of legume consumption and the risk of hypertriglyceridemia, high LDL-C, and low HDL-C. Therefore it is suggested that increasing legume intake may be an important part of a dietary approach for primary prevention of cardiovascular disease.

Definitions and potential health benefits of the Mediterranean diet: views from experts around the world

The Mediterranean diet has been linked to a number of health benefits, including reduced mortality risk and lower incidence of cardiovascular disease. Definitions of the Mediterranean diet vary across some settings, and scores are increasingly being employed to define Mediterranean diet adherence in epidemiological studies. Some components of the Mediterranean diet overlap with other healthy dietary patterns, whereas other aspects are unique to the Mediterranean diet. In this forum article, we asked clinicians and researchers with an interest in the effect of diet on health to describe what constitutes a Mediterranean diet in different geographical settings, and how we can study the health benefits of this dietary pattern.

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.

Estimation of the intake of phenol compounds from virgin olive oil of a population from southern Spain

The objective of the study was to determine the mean polyphenol composition of different varieties of virgin olive oil (VOO) habitually consumed in the region of southern Spain and to estimate the dietary exposure to olive oil polyphenols in that population. There were statistically significant differences in total polyphenols among varieties, with the Picual variety containing the largest amount with a mean value of 591.8 mg kg(-1). The main phenolic compounds found in the VOOs under study were tyrosol and hydroxytyrosol. The highest amounts of both substances were found in Picual olive oils with concentrations of 2.3-6.6 mg kg(-1). The total intake of polyphenols from VOO ranged between 8.2 mg day(-1) (SD = 4.14) for the under 19 year olds and 21.3 mg day(-1) (SD = 3) for the over 50 year olds. Some polyphenols, including tyrosol and hydroxytyrosol, were consumed principally as olive oil. The intake of these compounds in the studied population was in the range of 88.5-237.4 μg day(-1). This has particular importance as recent studies have demonstrated that hydroxytyrosol helps to improve plasma lipids levels and repair oxidative damage related to cardiovascular disease. There was a greater dietary consumption of polyphenols in olive oil among the participants who more closely followed the Mediterranean diet pattern. A higher consumption of olive oil and therefore a greater exposure to polyphenols was observed in females versus males and in participants of normal weight versus those who were overweight. The total intake of polyphenols from VOO significantly increased with higher age, reflecting the greater intake of this oil by older people, who also show a closer adherence to the Mediterranean diet. The over 50-year-old age group showed the greatest consumption of this olive oil and therefore of phenolic compounds, which are healthy protectors in the human diet that contribute to the acknowledged benefits of the Mediterranean diet.

[Folic acid intake before and after mandatory fortification: a population-based study in São Paulo, Brazil]

This study analyzed folic acid intake before and since mandatory fortification. Dietary data were collected by 24-hour recall in a health survey in São Paulo (ISA-Capital) in 2003 and 2007-2008, stratifying the population according to life stage and gender. Estimated average requirement (EAR) and tolerable upper intake level (UL) were used to assess intake. Prevalence of inadequate folic acid intake decreased in all groups, especially adolescents and adult males (72% to < 1% and 76% to 6%, respectively) but remained high in adult women (38%). Beans were the main source of folic acid before fortification. With fortification, bread became the main source, but beans remained important. Fortification was successful (increased intake within safe levels), but it raised concerns about the high proportion in the target group (adult women) who still fail to meet the recommended intake.

Nutritional and health benefits of dried beans

Dried beans (often referred to as grain legumes) may contribute to some of the health benefits associated with plant-based diets. Beans are rich in a number of important micronutrients, including potassium, magnesium, folate, iron, and zinc, and are important sources of protein in vegetarian diets. In particular, they are among the only plant foods that provide significant amounts of the indispensable amino acid lysine. Commonly consumed dried beans are also rich in total and soluble fiber as well as in resistant starch, all of which contribute to the low glycemic index of these foods. They also provide ample amounts of polyphenols, many of which are potent antioxidants. Intervention and prospective research suggests that diets that include beans reduce low-density lipoprotein cholesterol, favorably affect risk factors for metabolic syndrome, and reduce risk of ischemic heart disease and diabetes. The relatively low bean intakes of North Americans and northern Europeans can be attributed to a negative culinary image as well as to intestinal discomfort attributable to the oligosaccharide content of beans. Cooking practices such as sprouting beans, soaking and discarding soaking water before cooking, and cooking in water with a more alkaline pH can reduce oligosaccharide content. Promotional efforts are needed to increase bean intake.

Release of antioxidant capacity from five plant foods during a multistep enzymatic digestion protocol

This study aimed at elucidating the influence of food matrix on the release of antioxidant activity from five plant foods (apple, spinach, walnut, red bean, and whole wheat). To this purpose a protocol based on sequential enzymatic digestion was adopted. The total antioxidant capacity (TAC) of both solubilized and insoluble materials was measured at each step. Results showed that the overall TAC obtained by enzyme treatments was usually higher than that obtained by chemical extraction-based methods. In apple most of the TAC was released upon water washing and after pepsin treatment, whereas in spinach, beans, and whole wheat the TAC released by treatments with bacterial enzymes was prominent. Walnut had the highest TAC value, which was mainly released after pancreatin treatment. Therefore, the enzyme treatment is fundamental to estimate the overall potential TAC of foods having a high amount of polyphenols bound to dietary fiber or entrapped in the food matrix.

A review of the nutritional value of legumes and their effects on obesity and its related co-morbidities

Since the 1970s, the proportion of overweight and obese people in the United States has grown at an alarming rate. An awareness of the consequences of obesity on the health and well-being of individuals is evident in the plethora of strategic plans at the local and national levels, most of which have largely fallen short of their goals. If interventions continue to be unsuccessful, it is estimated that approximately three of four Americans will be overweight or obese by 2020. Prevention of excess weight gain can be accomplished with relatively small changes in lifestyle behaviours to control body weight. Small sustainable changes are perhaps better than efforts to achieve larger changes that cannot be sustained. Legumes can be a valuable food by which the needs of the undernourished or under-served populations could be met. They can be incorporated into meat products, such as sausages and burgers, to lower the energy density of these foods while providing important nutrients. Replacing energy-dense foods with legumes has been shown to have beneficial effects on the prevention and management of obesity and related disorders, such as cardiovascular disease, diabetes and the metabolic syndrome. This review explores the nutritional value and obesity-related health benefits of legume consumption while focusing on pulses.

Plant growth promotion in cereal and leguminous agricultural important plants: from microorganism capacities to crop production

Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria which actively colonize plant roots, exerting beneficial effects on plant development. The PGPR may (i) promote the plant growth either by using their own metabolism (solubilizing phosphates, producing hormones or fixing nitrogen) or directly affecting the plant metabolism (increasing the uptake of water and minerals), enhancing root development, increasing the enzymatic activity of the plant or "helping" other beneficial microorganisms to enhance their action on the plants; (ii) or may promote the plant growth by suppressing plant pathogens. These abilities are of great agriculture importance in terms of improving soil fertility and crop yield, thus reducing the negative impact of chemical fertilizers on the environment. The progress in the last decade in using PGPR in a variety of plants (maize, rice, wheat, soybean and bean) along with their mechanism of action are summarized and discussed here.