Role of fibre and fruit in the Mediterranean diet to protect against myocardial infarction: a case-control study in Spain

Intake of legumes and cardiovascular disease: A systematic review and dose-response meta-analysis

AIMS

To summarize the evidence on the association between the intake of legumes and the risk of cardiovascular disease (CVD) overall, coronary heart disease (CHD) and stroke, and to identify optimal intake levels for reduced disease risk through a systematic review and dose-response meta-analysis.

DATA SYNTHESIS

We have systematically searched PubMed, Scopus and Web of Science up to March, 2022 for the retrieval of intervention and observational studies (PROSPERO Reg. number: CRD42021247565). Pooled relative risks (RRs) comparing extreme categories of intake were computed using random-effects models. One-stage dose-response meta-analyses were also performed using random-effects models. 22 831 articles were screened resulting in 26 eligible observational studies (21 prospective cohort and 5 case-control studies). When comparing extreme categories of intake, the consumption of legumes was inversely associated with CVD (n = 25: RR = 0.94; 95%CI:0.89,0.99) and CHD (n = 16: RR = 0.90; 95%CI:0.85,0.96), but not with stroke (n = 9: RR = 1.00; 95%CI:0.93,1.08). We further found evidence for an inverse dose-response association with CHD, increasing in magnitude up to an intake of 400 g/week, after which the benefit seems to level-off.

CONCLUSIONS

The intake of legumes was associated with a reduced risk of CVD and CHD, but not with stroke, among individuals with the highest consumption levels. An intake level of 400 g/week seemed to provide the optimal cardiovascular benefit. Further research is needed to better understand the role of legumes in stroke subtypes.

Dietary fiber in the prevention of obesity and obesity-related chronic diseases: From epidemiological evidence to potential molecular mechanisms

Obesity is a mostly preventable diet-related disease and currently a major challenge for human populations worldwide. Obesity is a major risk factor for diseases such as type 2 diabetes mellitus (T2DM), cardiovascular disease (CVD) and certain cancers. Dietary fiber is a complex mixture of non-digestible molecules, mostly polysaccharides. Multiple epidemiological studies have demonstrated statistically significant reductions in risks of obesity, T2DM, CVD, colorectal cancer, and pre-menopausal breast cancer with higher dietary fiber intakes. Various direct and indirect mechanisms have been proposed including altered digestion and absorption, stimulation of gut hormones including glucagon-like-peptide-1 (GLP-1) and peptide YY (PYY), reduced appetite, and altered metabolism of bile and cholesterol. These may act via pathways involving G-protein-coupled receptors (GPRs), histone deacetylase (HDAC), and aromatase enzymes. Ultimately, fiber intake contributes to improving glucose levels and insulin sensitivity, lowering risk of T2DM, CVD and certain cancers. Therefore, diets rich in dietary fiber should be encouraged to prevent obesity and associated chronic disease.

Dietary and circulating vitamin C, vitamin E, β-carotene and risk of total cardiovascular mortality: a systematic review and dose-response meta-analysis of prospective observational studies

OBJECTIVE

The present review aimed to quantify the association of dietary intake and circulating concentration of major dietary antioxidants with risk of total CVD mortality.

DESIGN

Systematic review and meta-analysis.

SETTING

Systematic search in PubMed and Scopus, up to October 2017.ParticipantsProspective observational studies reporting risk estimates of CVD mortality across three or more categories of dietary intakes and/or circulating concentrations of vitamin C, vitamin E and β-carotene were included. A random-effects meta-analysis was conducted.

RESULTS

A total of fifteen prospective cohort studies and three prospective evaluations within interventional studies (320 548 participants and 16 974 cases) were analysed. The relative risks of CVD mortality for the highest v. the lowest category of antioxidant intakes were as follows: vitamin C, 0·79 (95 % CI 0·68, 0·89; I 2=46 %, n 10); vitamin E, 0·91 (95 % CI 0·79, 1·03; I 2=51 %, n 8); β-carotene, 0·89 (95 % CI 0·73, 1·05; I 2=34 %, n 4). The relative risks for circulating concentrations were: vitamin C, 0·60 (95 % CI 0·42, 0·78; I 2=65 %, n 6); α-tocopherol, 0·82 (95 % CI 0·76, 0·88; I 2=0 %, n 5); β-carotene, 0·68 (95 % CI 0·52, 0·83; I 2=50 %, n 6). Dose-response meta-analyses demonstrated that the circulating biomarkers of antioxidants were more strongly associated with risk of CVD mortality than dietary intakes.

CONCLUSIONS

The present meta-analysis demonstrates that higher vitamin C intake and higher circulating concentrations of vitamin C, vitamin E and β-carotene are associated with a lower risk of CVD mortality.

Consumption of Fruit or Fiber-Fruit Decreases the Risk of Cardiovascular Disease in a Mediterranean Young Cohort

Fiber and fiber-rich foods have been inversely associated with cardiovascular disease (CVD), but the evidence is scarce in young and Mediterranean cohorts. We used Cox regression models to assess the association between quintiles of total fiber and fiber from different sources, and the risk of CVD adjusted for the principal confounding factors in a Mediterranean cohort of young adults, the SUN (Seguimiento Universidad de Navarra, Follow-up) cohort. After a median follow-up of 10.3 years, we observed 112 cases of CVD among 17,007 participants (61% female, mean age 38 years). We observed an inverse association between fiber intake and CVD events (p for trend = 0.024) and also between the highest quintile of fruit consumption (hazard ratio (HR) 0.51, 95% confidence interval (CI) 0.27–0.95) or whole grains consumption (HR 0.43 95% CI 0.20–0.93) and CVD compared to the lowest quintile, and also a HR of 0.58 (95% CI 0.37–0.90) for the participants who ate at least 175 g/day of fruit. Only the participants in the highest quintile of fruit-derived fiber intake had a significantly lower risk of CVD (HR 0.52, 95% CI 0.28–0.97). The participants who ate at least one serving per week of cruciferous vegetables had a lower risk than those who did not (HR 0.52, 95% CI 0.30–0.89). In conclusion, high fruit consumption, whole grain consumption, or consumption of at least one serving/week of cruciferous vegetables may be protective against CVD in young Mediterranean populations.

Dietary patterns and cardiovascular risk factors in adolescents and young adults: the Northern Ireland Young Hearts Project

Dietary pattern (DP) analysis allows examination of the combined effects of nutrients and foods on the markers of CVD. Very few studies have examined these relationships during adolescence or young adulthood. Traditional CVD risk biomarkers were analysed in 12–15-year-olds (n487; Young Hearts (YH)1) and again in the same individuals at 20–25 years of age (n487; YH3). Based on 7 d diet histories, in the present study, DP analysis was performed usinga posterioriprincipal component analysis for the YH3 cohort and thea prioriMediterranean Diet Score (MDS) was calculated for both YH1 and YH3 cohorts. In thea posterioriDP analysis, YH3 participants adhering most closely to the ‘healthy’ DP were found to have lower pulse wave velocity (PWV) and homocysteine concentrations, the ‘sweet tooth’ DP were found to have increased LDL concentrations, systolic blood pressure, and diastolic blood pressure and decreased HDL concentrations, the ‘drinker/social’ DP were found to have lower LDL and homocysteine concentrations, but exhibited a trend towards a higher TAG concentration, and finally the ‘Western’ DP were found to have elevated homocysteine and HDL concentrations. In thea prioridietary score analysis, YH3 participants adhering most closely to the Mediterranean diet were found to exhibit a trend towards a lower PWV. MDS did not track between YH1 and YH3, and nor was there a longitudinal relationship between the change in the MDS and the change in CVD risk biomarkers. In conclusion, cross-sectional analysis revealed that some associations between DP and CVD risk biomarkers were already evident in the young adult population, namely the association between the healthy DP (and the MDS) and PWV; however, no longitudinal associations were observed between these relatively short time periods.

Consumption of nuts and legumes and risk of incident ischemic heart disease, stroke, and diabetes: a systematic review and meta-analysis

BACKGROUND

Relations between the consumption of nuts and legumes and risk of ischemic heart disease (IHD), stroke, and diabetes have not been well established.

OBJECTIVE

We systematically investigated and quantified associations of nut and legume consumption with incident IHD, stroke, and diabetes.

DESIGN

We systematically searched multiple databases to identify randomized controlled trials or observational studies that examined the relations. Studies were excluded if they reported only intermediate physiologic measures, soft cardiovascular outcomes, or crude risk estimates. Data were extracted independently and in duplicate. We assessed pooled dose-response relations by using a generalized least-squares trend estimation, and prespecified sources of heterogeneity were assessed by using metaregression. The potential for publication bias was explored by using funnel plots, Begg's and Egger's tests, and Duval and Tweedie trim-and-fill methods.

RESULTS

Of 3851 abstracts, 25 observational studies (23 prospective and 2 retrospective studies) and 2 trial reports met inclusion criteria and comprised 501,791 unique individuals and 11,869 IHD, 8244 stroke, and 14,449 diabetes events. The consumption of nuts was inversely associated with fatal IHD (6 studies; 6749 events; RR per 4 weekly 28.4-g servings: 0.76; 95% CI: 0.69, 0.84; I(2) = 28%), nonfatal IHD (4 studies; 2101 events; RR: 0.78; 0.67, 0.92; I(2) = 0%), and diabetes (6 studies; 13,308 events; RR: 0.87; 0.81,0.94; I(2) = 22%) but not stroke (4 studies; 5544 events). Legume consumption was inversely associated with total IHD (5 studies; 6514 events; RR per 4 weekly 100-g servings: 0.86; 0.78, 0.94; I(2) = 0%) but not significantly associated with stroke (6 studies; 6690 events) or diabetes (2 studies; 2746 events). A meta-regression did not identify the effect modification by age, duration of follow-up, study location, or study quality. Mixed evidence was seen for publication bias, but analyses by using the Duval and Tweedie trim-and-fill method did not appreciably alter results.

CONCLUSION

This systematic review supports inverse associations between eating nuts and incident IHD and diabetes and eating legumes and incident IHD.

Total antioxidant capacity of the Korean diet

BACKGROUND/OBJECTIVES

The objective of this study was to measure and/or estimate the total antioxidant capacity of the Korean diet.

MATERIALS/METHODS

Eighty-one plant foods that were expected to exhibit rather high antioxidant activities were selected from the Korean diet using the Fifth Korean National Health and Nutrition Survey (KNHANES V). These foods were categorized into 11 food groups: cereals, potatoes, legumes, nuts, vegetables, kimchies, mushrooms, fruits, fruit juices, sea weeds, and oils. The foods were mixed in the proportions specified in traditional Korean recipes and analyzed. The measured indicators for antioxidant capacities were total phenolics, 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), and Trolox equivalent antioxidant capacity (TEAC).

RESULTS

Total phenolics were high in the fruit juices, nuts, vegetables, and fruits; and the average DPPH, ORAC, and TEAC values were high in the vegetables, fruits, fruit juices, and nuts. The correlation coefficient between the content of total phenolics of each food and the in vitro antioxidant capacity was relatively high at 0.851. The intake of total phenolics per capita per day in the Republic of Korea was estimated to be 127 mg. The total dietary antioxidant capacity (TDAC) values, which were obtained from the total antioxidant capacity of each food, taking into account the intake of each food, were 20,763, 54,335, and 876.4 µmol of Trolox equivalents using the DPPH, ORAC, and TEAC methods, respectively. The food group that contributed the most to the Korean TDAC was cereals at 39.7%, followed by fruits and vegetables at 27.8% and 13.9%, respectively. The contribution of legumes, nuts, fruit juices, and mushrooms was quite minimal at less than 2% each.

CONCLUSIONS

The content of total phenolics and the antioxidant capacity of the Korean diet are significantly correlated and the high contributing food groups are cereals, fruits, and vegetables.

The influence of raw and processed garlic and onions on plasma classical and non-classical atherosclerosis indices: investigations in vitro and in vivo

Garlic and white and red varieties of onion were subjected to processing by a variety of culinary methods, and bioactive compounds then determined. For in vivo studies, 84 male Wistar rats were randomly divided into 14 diet groups, each of six rats, including two control groups (one with no supplementation and one with cholesterol supplementation only). During the 30-day trial, the basal diets of the other 12 groups were supplemented with 1% cholesterol and raw or processed vegetables. Both raw red onion and red onion subjected to blanching for 90 s hindered the rise in plasma lipids more than the other vegetables studied in the supplemented diets. The decrease in antioxidant activity compared to the cholesterol-supplemented control group was significantly less for the group fed with red onion subjected to blanching for 90 s. No histological changes were detected in the studied organs of rats that had been fed cholesterol. In conclusion, blanching for 90 s most fully preserved the bioactive compounds and antioxidant potentials, and hindered the rise in plasma lipid levels and the decrease in plasma antioxidant activity of rats fed cholesterol. Alkaline phosphatase levels correlated with classical atherosclerosis indices, and determination of alkaline phosphatase is suggested as an additional index in atherosclerosis testing.

Can pure fruit and vegetable juices protect against cancer and cardiovascular disease too? A review of the evidence

While it is widely accepted that fruit and vegetables (F&V) lower the risk of cancer, and cardiovascular disease (CVD), the role of pure fruit and vegetable (PFV) juices is often downplayed. This review poses two questions: Are the protective benefits of F&V dependent upon constituents lacking in PFV juices (e.g. fibre)? Do PFV juices impact on disease risk when considered separately from F&V? Studies comparing the effects of fibre and antioxidants were reviewed, yielding the finding that the impact of F&V may relate more strongly to antioxidants, than to fibre. For the second question, high-quality published studies that considered PFV juices were reviewed. The impact of PFV juices on cancer risk was weakly positive, although a lack of human data and contradictory findings hampered conclusions. For CVD, there was convincing evidence from epidemiological and clinical studies that PFV juices reduced risk via a number of probable mechanisms. It was concluded that the view that PFV juices are nutritionally inferior to F&V, in relation to chronic disease risk reduction, is unjustified.

Increased consumption of fruit and vegetables is related to a reduced risk of coronary heart disease: meta-analysis of cohort studies

Increased consumption of fruit and vegetables has been shown to be associated with a reduced risk of coronary heart disease (CHD) in many epidemiological studies, however, the extent of the association is uncertain. We quantitatively assessed the relation between fruit and vegetable intake and incidence of CHD by carrying out a meta-analysis of cohort studies. Studies were included if they reported relative risks (RRs) and corresponding 95% confidence interval (CI) of CHD with respect to frequency of fruit and vegetable intake. Twelve studies, consisting of 13 independent cohorts, met the inclusion criteria. There were 278,459 individuals (9143 CHD events) with a median follow-up of 11 years. Compared with individuals who had less than 3 servings/day of fruit and vegetables, the pooled RR of CHD was 0.93 (95% CI: 0.86-1.00, P=0.06) for those with 3-5 servings/day and 0.83 (0.77-0.89, P<0.0001) for those with more than 5 servings/day. Subgroup analyses showed that both fruits and vegetables had a significant protective effect on CHD. Our meta-analysis of prospective cohort studies demonstrates that increased consumption of fruit and vegetables from less than 3 to more than 5 servings/day is related to a 17% reduction in CHD risk, whereas increased intake to 3-5 servings/day is associated with a smaller and borderline significant reduction in CHD risk. These results provide strong support for the recommendations to consume more than 5 servings/day of fruit and vegetables.

Frequency of fruit and vegetable consumption and coronary heart disease in France and Northern Ireland: the PRIME study

Fruit and vegetable consumption is associated with low CHD risk in the USA and Northern Europe. There is, in contrast, little information about these associations in other regions of Europe. The goal of the present study was to assess the relationship between frequency of fruit and vegetable intake and CHD risk in two European populations with contrasting cardiovascular incidence rates; France and Northern Ireland. The present prospective study was in men aged 50–59 years, free of CHD, who were recruited in France (n 5982) and Northern Ireland (n 2105). Fruit and vegetable intake was assessed by a food-frequency questionnaire. Incident cases of acute coronary events and angina were recorded over a 5-year follow-up. During follow-up there was a total of 249 ischaemic events. After adjustment on education level, smoking, physical activity, alcohol consumption, employment status, BMI, blood pressure, serum total and HDL-cholesterol, the relative risks (RR) of acute coronary events were 0·67 (95% CI 0·44, 1·03) and 0·64 (95% CI 0·41, 0·99) in the 2nd and 3rd tertiles of citrus fruit consumption, respectively (P for trend <0·03). Similar results were observed in France and Northern Ireland. In contrast, the RR of acute coronary events for ‘other fruit’ consumption were 0·70 (95% CI 0·31, 1·56) and 0·52 (95% CI 0·24, 1·14) respectively in Northern Ireland (trend P<0·05) and 1·29 (95% CI 0·69, 2·4) and 1·15 (95% CI 0·68, 1·94) in France (trend P=0·5; interaction P<0·04). There was no evidence for any association between vegetable intake and total CHD events. In conclusion, frequency of citrus fruit, but not other fruits, intake is associated with lower rates of acute coronary events in both France and Northern Ireland, suggesting that geographical or related factors might affect the relationship between fruit consumption and CHD risk.

Vegetable protein and fiber from cereal are inversely associated with the risk of hypertension in a Spanish cohort

BACKGROUND

Some cross-sectional studies suggest that fiber and protein intake can be associated with lower levels of blood pressure, but results from prospective cohorts are scarce and none has been conducted outside the U.S.

METHODS

The SUN cohort followed-up prospectively 5880 Spanish men and women older than 20 years of age, all university graduates. Dietary information was gathered at baseline with a previously validated semiquantitative food frequency questionnaire. New cases of medically diagnosed hypertension (HT) were identified through responses to a mailed questionnaire after at least 2 years from recruitment.

RESULTS

One hundred and eighty new cases of HT were ascertained after a median follow-up of 28 months. After adjustment for potential confounders and several dietary factors, participants in the highest quintile of vegetable protein intake had a lower risk of incident HT compared with those in the lowest quintile [hazard ratio (HR) = 0.5, 95% confidence interval (CI) 0.2-0.9, p for trend = 0.06]. Similarly, fiber from cereals was inversely associated with a lower risk of HT (HR comparing fifth vs. first quintile = 0.6, 95% CI 0.3-1.0, p for trend = 0.05). Risk reduction was more important among men and obese and older individuals. Total or animal protein and total fiber as well as fiber from other sources different from cereal were not associated with the risk of HT.

CONCLUSIONS

In this Mediterranean cohort, dietary intake of vegetable protein and fiber from cereals was associated with a lower risk of HT when other nutrients were also taken into consideration.

The SUN cohort study (Seguimiento University of Navarra)

OBJECTIVE

Cohort study (the SUN project) to identify dietary determinants of hypertension, diabetes, obesity and coronary heart disease (CHD), among other conditions.

DESIGN

The SUN project is a Mediterranean dynamic prospective follow-up (cohort) study assessing participants every 2 years. The recruitment started in 2000 and it is permanently open (this is a dynamic cohort). A preliminary case-control study of myocardial infarction was also conducted, selecting incident cases of myocardial infarction and matched hospital controls.

SETTING

The SUN study is conducted in Spain with university graduates, most of them being former students of the University of Navarra. The case-control study was conducted in three tertiary hospitals in the city of Pamplona (Spain).

SUBJECTS

The case-control study included 171 cases and 171 controls. We have currently enrolled more than 17,500 participants in the SUN cohort. Approximately 7500 of them were enrolled less than 2 years ago, and have not received yet the invitation to complete the 2-year follow-up assessment. The follow-up rate for the first 10,000 participants approaches 90%.

RESULTS

The case-control study found inverse associations between olive oil (or adherence to a Mediterranean food pattern) and myocardial infarction. In the SUN cohort, after 28.5 months of follow-up a higher adherence to a Mediterranean food pattern rich in olive oil was associated with a reduced risk of hypertension, though the results were statistically significant only among men.

CONCLUSIONS

The SUN study and the accompanying case-control study support the benefits of a Mediterranean diet and olive oil against CHD and hypertension.

Association of fiber intake and fruit/vegetable consumption with weight gain in a Mediterranean population

OBJECTIVE

We assessed the association between fiber intake and fruit/vegetable consumption with the likelihood of weight gain in the previous 5 y in a Mediterranean population.

METHODS

We conducted a cross-sectional analysis of participants (5094 men and 6613 women) in a multipurpose prospective cohort (Seguimiento Universidad de Navarra Study). Diet was measured by using a semiquantitative food-frequency questionnaire that was previously validated in Spain. We calculated the odds ratios of weight gain in the previous 5 y according to quintiles of energy-adjusted fiber intake and quintiles of energy-adjusted of fruit/vegetable consumption. We also considered the joint exposure to fiber intake and fruit/vegetable consumption.

RESULTS

Multivariate-adjusted odds ratios for weight gain across quintiles 1 to 5 of fiber intake were 1.00 (reference), 0.86, 0.86, 0.70, and 0.52 (P for trend < 0.001) among men and 1.00 (reference), 0.99, 1.08, 1.05, and 0.72 (P for trend = 0.005) among women. We also observed a significant inverse association between total fruit/vegetable consumption and weight gain, but only among men (adjusted odds ratios, 0.78, 0.89, 0.70, and 0.54 for quintiles 2 to 5, P for trend < 0.001). The inverse association between fruit/vegetable consumption and weight gain in the previous 5 y was more evident among those with a high intake of total fiber, and the benefit of total fiber was more evident among those with a high consumption of fruits and vegetables.

CONCLUSIONS

This study provides additional support to the inverse association between fiber or fruit/vegetable consumption and weight gain, thus emphasizing the importance of replacing some dietary compounds by such foods and fiber-rich products, which may help to avoid weight gain.

Decreased consumption of dried mature beans is positively associated with urbanization and nonfatal acute myocardial infarction

Legumes may protect against myocardial infarction (MI). The objective of this study was to determine whether consumption of dried mature beans (referred to as beans), the main legume in Latin America, is associated with MI. The cases (n = 2119) were survivors of a first acute MI and were matched by age, sex, and area of residence to randomly selected population controls (n = 2119) in Costa Rica. Dietary intake was assessed with a validated FFQ. Of the population, 69% consumed > or = 1 serving of beans/d (1 serving = one-third cup of cooked beans, approximately 86 g). Consumption of > or = 1 serving/d was significantly higher (P < 0.001) in rural (81%) than in urban (65%) areas. Individuals who never eat dried beans or whose consumption was < 1 time/mo were classified as nonconsumers. Compared with nonconsumers, intake of 1 serving of beans/d was inversely associated with MI in analyses adjusted for smoking, history of diabetes, history of hypertension, abdominal obesity, physical activity, income, intake of alcohol, total energy, saturated fat, trans fat, polyunsaturated fat, and cholesterol [odds ratio (OR) = 0.62; 95% CI: 0.45-0.88]. No further protection was observed with increased number of servings/d (OR = 0.73; 95% CI: 0.52-1.03 for > 1 serving/d). In summary, we found that consumption of 1 serving of beans/d is associated with a 38% lower risk of MI. No additional protection was observed at intakes > 1 serving/d. These findings are timely given the trend toward increased obesity, cardiovascular disease, and a reduction in the intake of beans in Latin American countries.

Development of a short dietary intake questionnaire for the quantitative estimation of adherence to a cardioprotective Mediterranean diet

Our objective was to develop a short questionnaire that can be easily used to estimate quantitatively the level of adherence to cardioprotective Mediterranean diets. The short questionnaire assessed the consumption of cardioprotective elements included in the Mediterranean diet (olive oil, wine, fruits, vegetables, fish, legumes and whole-grain intake). A low consumption of meat or meat-products was also included in the composite score. The relative risk of myocardial infarction for each category of the composite score obtained (range 0-9) was computed using data from a case-control study that included 171 cases of first myocardial infarction and 171 matched controls. We found an adjusted odds ratio=0.18 (95% confidence interval (CI): 0.03-0.97; P=0.04) for those scoring 7-9 points when comparing them with those scoring 1-2 points. An increment of one point in the score was associated with an 18% reduction in the relative risk of myocardial infarction (P=0.05).

Adherence to the traditional mediterranean diet is inversely associated with body mass index and obesity in a spanish population

The Mediterranean diet is a healthy eating pattern with protective effects on chronic diseases. The purpose of this study was to assess the relation between BMI and obesity and the level of adherence to the traditional Mediterranean diet. The subjects were Spanish men (n = 1547) and women (n = 1615) aged 25-74 y who were examined in 1999-2000, in a population-based, cross-sectional survey in the northeast of Spain (Girona). Dietary intake was assessed using a FFQ. A Mediterranean diet score, including foods considered to be characteristic components of the traditional Mediterranean diet (vegetables, fruits, pulses, nuts, fish, meat, cereals, olive oil, and wine) was created. An increase of 5 U in the dietary score was associated with a change in the BMI of 0.43 (P = 0.030) and 0.68 (P = 0.007), after controlling for potential confounders, in men and women, respectively. The obesity risk decreased in men (P = 0.010) and women (P = 0.013) with increasing adherence to the traditional Mediterranean dietary pattern. The population in the top tertile of this score were less likely to be obese in both genders [odds ratio (OR) and (95% CI): 0.61 (0.40-0.92) in men; 0.61 (0.40-0.93) in women] after adjusting for potential confounders. These data suggest that the traditional Mediterranean dietary pattern is inversely associated with BMI and obesity. This finding may be useful in the development of dietary approaches for dietary counseling and the prevention of obesity.

A Mediterranean dietary style influences TNF-alpha and VCAM-1 coronary blood levels in unstable angina patients

BACKGROUND

A Mediterranean dietary pattern has been associated with a reduced risk of coronary heart disease, as well as a reduction of oxidative stress, but studies indicating possible interactions between food intake and inflammatory mediators production at specific sites are lacking.

AIM OF THE STUDY

To assess the relationship between Mediterranean diet consumption and inflammatory related molecules production in coronary vessels.

METHODS

A previously reported Mediterranean-diet score was computed summing-up the quintiles of eight dietary components from a validated food frequency questionnaire in 24 patients with unstable angina. Tumor necrosis factor (TNF-alpha) and vascular cell adhesion molecule (VCAM-1) concentrations were measured in coronary sinus blood.

RESULTS

Both biomarkers showed an inverse association with the Mediterraneandiet score. The association between VCAM-1 and the Mediterranean-diet score had an adjusted beta coefficient of -35.1 ng/ml (95% coefficient interval, CI: -63.5 to -6.7). The adjusted beta coefficient using TNF-alpha as the dependent variable was -41.6 pg/ml (95 % CI: -76.2 to -7.1). The consumption of olive oil as a single item showed a significant inverse association, and a Mediterranean-diet score excluding olive oil was also inversely associated with TNF-alpha and VCAM-1 serum levels in coronary venous blood.

CONCLUSIONS

Adherence to a Mediterranean dietary pattern may protect against coronary artery wall production of inflammatory mediators. This finding could provide a novel mechanistic explanation for the recognized lower coronary risk associated with a Mediterranean diet.

Dietary fiber and coronary disease: does the evidence support an association?

Large, prospective, epidemiologic studies show a protective effect of dietary fiber against coronary heart disease (CHD) and form the basis for new recommendations from the National Academy of Science for fiber intake (38 and 25 g/d for young men and women, respectively, based on an intake of 14 g of fiber per 1000 kcal). Mechanisms by which fibers may protect against CHD include lowering blood cholesterol (soluble fibers), attenuating blood triglyceride levels (mostly soluble fibers), decreasing hypertension (all fibers), and normalizing postprandial blood glucose levels (all fibers). An important consideration in making diet recommendations to protect against CHD is that the total amount of fiber from fiber-containing foods is important, and individuals should not just be counseled to focus on soluble fiber.

Ballaststoffe: Mehr als ein Diätmittel

A nutrition rich in fibre has a preventive effect against constipation, colon diverticulosis, carcinoma of the large bowel and stomach, type 2-diabetes, metabolic syndrome and cardiovascular disease. In case of constipation, diverticulosis and diabetes this effect solely depends on dietary fibre. Regarding carcinomas and cardiovascular diseases, so far unknown factors integrated in or associated with fibre-rich food may also contribute to the preventive effect. Therapy with dietary fibre is indicated for constipation, colon diverticulosis, diarrhea, diabetes, and hypercholesterinemia. The individual dietary fibres differ substance-specifically. Food-integrated dietary fibre such as whole-grain bread, vegetables and fruit have their place in prevention. Dietary fibre preparations such as wheat bran, flax seed or sugar-beet fibre are useful in the treatment of constipation, colon diverticulosis and adiposity. Oat bran is preferentially used in hypercholesterinemia. Purified dietary fibres such as cellulose, guar, psyllium, and beta-glucan have an anti-diabetic, all viscous fibres an anti-lipaemic effect. The therapeutic dosages of dietary fibre preparations are 20-40 g/day and of purified fibres substances 10-20 g/day respectively.

The intake of dietary indigestible fraction in the Spanish diet shows the limitations of dietary fibre data for nutritional studies

OBJECTIVE

To compare the intakes of dietary fibre (DF) and dietary indigestible fraction (DIF) in the Spanish diet and also to show the limitations of DF values for nutritional and epidemiological studies.

DESIGN

This includes the following: (i) estimation of plant foods consumption in Spanish diet from national food consumption data obtained from annual surveys (6000 households, 700 hotels and restaurants and 200 institutions); (ii) determination of DIF content in plant foods using analytical methods that mimic physiological conditions; (iii) estimation of daily intakes of DIF and DF in the Spanish diet.

RESULTS

DIF intake in the Spanish population was estimated at 41.5 g/person/day. DF intake (18.3 g/person/day) was considerably lower than the amount of carbohydrate necessary to maintain the daily bacterial cell turnover in large intestine ('carbohydrate gap'). The differences between DIF and DF values are a consequence of conceptual and methodological aspects. DIF, as the part of foods reaching the colon, comprises not only DF but also other indigestible compounds such as a fraction of resistant starch, protein, polyphenols and other associated compounds. Analytical conditions are closer to actual physiological conditions in the determination of DIF than in DF analysis.

CONCLUSIONS

DF intake underestimates a major part of the dietary substrates that enter the colon. DIF intake more closely matches the amount of substrates needed to maintain a typical human colonic microflora. DIF may be a good alternative to DF for nutritional and epidemiological studies.

To what extent are the effects of diet on coronary heart disease lipid-mediated?

BACKGROUND

Cohort and case-control studies support the effect of diet on coronary heart disease. The objective of this study was to analyze the strength of the influence of dietary fat subtypes and other nutrients on serum lipids levels in patients with a first acute myocardial infarction.

METHODS

We studied 139 patients with a first myocardial infarction and no previous history of vascular disease. Serum lipids were determined, and nutrient intake was analyzed using a validated 118-food item questionnaire.

RESULTS

Multiple regression models found weak but significant associations between the intake of different fatty acids and total to HDL cholesterol ratio (atherogenic index) when we adjusted for age, gender and body mass index (BMI). Positive associations with serum HDL cholesterol concentration were observed for energy-adjusted intake of red wine, alcohol intake, and omega-3 fatty acids intake. However, these nutrients explained less than 12% of the variability in the atherogenic index, and less than 17% in the variability of HDL.

CONCLUSIONS

Our results suggest only a modest contribution of the investigated nutrients on serum lipids (atherogenic index and HDL cholesterol) in coronary patients. Alternative mechanisms of dietary factors not directly related with serum lipids or, more likely, a global effect of diet on inflammatory and antioxidant parameters should be studied in order to better understand the nature of dietary habits' influence on cardiovascular disease.

Population dietary habits and physical activity modification with age

OBJECTIVE

The aim of the present study was to analyse the relation between age and both dietary habits and leisure-time physical activity, and to determine nutrient inadequacy of aged groups in our population.

DESIGN

Cross-sectional study.

SETTING

A random sample of the 25-74-y-old population of Gerona, Spain.

SUBJECTS

A total of 838 men and 910 women were selected from among the general population according to the 1991 census.

OUTCOME MEASURES

Analysis of dietary habits, including amount and type of alcohol consumption, and detailed evaluation of leisure-time physical activity.

RESULTS

Nutrient densities of carbohydrates, vitamin B(1), vitamin B(12), vitamin C, vitamin E, folate, potassium, iron, magnesium, copper, and dietary fiber increased significantly (P<0.05) with age in both genders, whereas an inverse trend was observed for total fat, saturated fatty acids, cholesterol, and sodium. Multiple linear regression analysis revealed a direct association of healthy dietary habits, characterized through a composite dietary score, with age after adjusting for several confounders both in men and women (P<0.001). This score was composed of folate, vitamin C, vitamin E, beta-carotene, dietary fibre, cholesterol, saturated fatty acids, and sodium. In all, 29 and 10% of male and female subjects aged 65-74 y, respectively, reported inadequate intakes of six or more of 16 nutrients. Total leisure-time physical activity increased with age in men (P<0.002), and was not different among female age groups.

CONCLUSION

Dietary behaviours and levels of physical activity spent during leisure time indicate a healthy lifestyle of the aged men and women in the present population. Nutrient inadequacy observed in some aged men and women, however, deserves particular intervention of health-care programmes for this growing part of our society.