The Mediterranean diet -- rich in fruits, vegetables, fish, olive oil, nuts and whole grains -- has long been hailed as a heart-healthy eating plan. But new research suggests its health benefits may be limited to the rich and well-educated. 
 
 For the study, a team of Italian scientists reviewed diets, income and education level of nearly 19,000 men and women. 
 
 The investigators found the Mediterranean diet was associated with about a 60 percent lower risk of heart disease and stroke among those with higher incomes and more education. The same was not true for those with fewer resources -- even though they followed a similar eating plan. 
 
 Healthy habits -- such as getting regular exercise, routine check-ups, and not smoking -- are more common among people with higher incomes. But the study findings held up even after the researchers accounted for these variables and others, such as marital status and body mass index (a measurement based on height and weight). 
 
 Will a Mediterranean diet help you live longer? 
 
 The team investigated other possible explanations for this healthy diet disparity. The findings showed that the wealthier participants ate less meat and consumed more fish and whole grains than those with lower incomes. 
 
 The more affluent people also ate a greater variety of fruits and vegetables, which provided more antioxidants and other essential nutrients. The researchers concluded that food quality may be as important for health as how much people eat and how often. 
 
 "Money may provide access to a larger variety of foods typical of the Mediterranean diet, such as fruits and vegetables, thus obtaining more adequate intake of essential nutrients," said the study's leader, Giovanni de Gaetano. He's head of the department of epidemiology and prevention at the I.R.C.C.S. Neuromed Institute in Pozzilli, Italy. 
 
 Many of the most nutritionally valuable foods in the Mediterranean diet -- including fish, olive oil and produce -- aren't cheap. 
 
 "Let's think about a five-member family who wants to attain to the five-a-day portion of fruits and vegetables," de Gaetano said. "This sounds quite expensive." 
 
 Cooking methods also differed among the study participants. The people with more money and education were more likely to prepare their vegetables in healthier ways, which preserve their nutritional value. 
 
 Joan Salge Blake is a clinical associate professor and dietetic internship director at Boston University. She said the more affluent "are more likely to have better health care, access to a variety of diverse fruits and vegetables, and an overall understanding about the role of lifestyle and diet in disease prevention." 
 
 So, she added, "costs and access to healthy foods will clearly impact the quality of a person's diet and lifestyle." 
 
 That doesn't mean individuals and families on a tight budget can't afford to follow the Mediterranean diet, Salge Blake stressed. She offered the following budget-friendly advice: 
 
 Look for variety and sales. When it comes to overall diet quality, the more fruit and veggies on your plate, the better. Choose produce that is on sale, which will stretch your food dollar. 
 
 Buy in-season. Produce tastes a lot better when it's in season. It's also much less expensive. Bottom line: you're more likely to eat fruit if it's sweet and you'll probably load up on veggies if they are more flavorful. 
 
 Don't overcook. How you cook vegetables can affect their nutritional value. "Typically, the less cooking time will cause the least loss of nutrients," Salge Blake said. 
 
 Consider frozen and canned foods. "Canned fish and frozen veggies and fruit are oftentimes more affordable than fresh, and can pack an equal, if not more, nutrient punch per bite," Salge Blake said. 
 
 Try affordable alternatives. Olive oil is considered a staple of the Mediterranean diet but it's pricey. "Other plant oils -- such as soybean oil -- are healthy and affordable, so you don't have to consume only olive oil," Salge Blake said. She noted the Mediterranean diet contains legumes, such as dried beans and peas, which are extremely affordable. 
 
 The study was published online July 31 in the International Journal of Epidemiology. 

 Abstract 
 
 Background It is uncertain whether the cardiovascular benefits associated with Mediterranean diet (MD) may differ across socioeconomic groups. Methods Prospective analysis on 18991 men and women aged ≥35 years from the general population of the Moli-sani cohort (Italy). Adherence to MD was appraised by the Mediterranean diet score (MDS). Household income (euros/year) and educational level were used as indicators of socioeconomic status. Hazard ratios (HR) were calculated by multivariable Cox proportional hazard models. Results Over 4.3 years of follow-up, 252 cardiovascular disease (CVD) events occurred. Overall, a two-point increase in MDS was associated with 15% reduced CVD risk (95% confidence interval: 1% to 27%). Such association was evident in highly (HR = 0.43; 0.25–0.72) but not in less (HR = 0.94; 0.78–1.14) educated subjects (P for interaction = 0.042). Similarly, CVD advantages associated with the MD were confined to the high household income group (HR = 0.39; 0.23–0.66, and HR = 1.01; 0.79–1.29 for high- and low-income groups, respectively; P for interaction = 0.0098). In a subgroup of individuals of different socioeconomic status but sharing similar MDS, diet-related disparities were found as different intakes of antioxidants and polyphenols, fatty acids, micronutrients, dietary antioxidant capacity, dietary diversity, organic vegetables and whole grain bread consumption. Conclusions MD is associated with lower CVD risk but this relationship is confined to higher socioeconomic groups. In groups sharing similar scores of adherence to MD, diet-related disparities across socioeconomic groups persisted. These nutritional gaps may reasonably explain at least in part the socioeconomic pattern of CVD protection from the MD. 
 
 Introduction 
 
 Observational studies have documented the association of Mediterranean-like dietary patterns with reduced cardiovascular disease (CVD) incidence and mortality,1–4 along with lower rates of cancer,5 neurodegenerative diseases and all-cause mortality.6,7 More recently, evidence on cardiovascular protection from an MD was provided also by intervention studies showing reduced risk of CVD after allocation to MD-like patterns both in primary8 and in secondary cardiovascular prevention.9 Diet quality exhibits a socioeconomic (SES) gradient, with less advantaged groups reporting lower adherence to healthy dietary patterns including an MD10 generally associated with poor health outcomes and higher prevalence of non-dietary unhealthy behaviours, such as tobacco use and inadequate physical activity.11 
 
 So far, SES inequities in diet have been documented for several domains of dietary behaviours and beyond food and nutrient intake; disparities were found for nutrient density levels, percentage contribution of food to nutrition and energy and also for diet variety, access to organic foods and food purchasing behaviours.12,13 During recent years, increased attention has been paid to the food processing pertinent to the MD which can influence the nutritional quality of foods, with consequent impact on future health outcomes, especially in relation to oxidative stress and inflammation.14 Actually, when measuring adherence to an MD, a relatively large amount of diet-related information or dietary behaviours is left out, and nutritional gaps among SES groups may still hold even in the presence of an apparently similar adherence to the same eating pattern.13 
 
 The aim of the present study is 3-fold: first, to evaluate the association between adherence to the MD and the incidence of fatal and non-fatal CVD events among adults initially free from CVD and diabetes; second, to test whether the association of the MD with CVD differs across SES strata; finally, to explore possible persisting diet-related differences among SES groups reaching similar scores of adherence to the MD. 
 
 Methods 
 
 Study population 
 
 The Moli-sani study is a prospective cohort study of 24 325 men and women (aged ≥ 35) randomly recruited from the general population of a Southern Italian region from March 2005 to April 2010.15 For the purpose of this study, individuals with a history of CVD (7.1%), diabetes (10.6%), those reporting implausible energy intakes (<800 kcal/day in men and <500 kcal/day in women or >4000 kcal/day in men and >3500 kcal/day in women; 3.2%), subjects with missing information on educational level (0.2%), unreliable medical or dietary questionnaires (1% and 3.9%, respectively), subjects lost to follow-up (0.2%) or with incomplete personal data (1.7%) were excluded from the analyses. The final sample consisted of 18 991 individuals. 
 
 The Moli-sani study complies with the Declaration of Helsinki and was approved by the ethical committee of the Catholic University in Rome, Italy. All participants provided written informed consent. 
 
 Ascertainment of cases 
 
 Primary fatal and nonfatal incident cases of CHD (unstable angina, myocardial infarction, coronary revascularization and sudden death from unspecified cardiac event) and cerebrovascular disease which occurred in the cohort during follow-up were ascertained by linkage of the study cohort to the hospital discharge files and to the regional Registro Nominativo delle Cause di Morte (ReNCaM) registry and death certificates (Istituto Nazionale di Statistica (ISTAT) form), by using the International Classification of Diseases, ninth revision (ICD-9). For CHD, ICD-9 codes 410–414 and/or reperfusion procedure (ICD-9 codes 36.0–36.9) and for cerebrovascular disease, ICD9 codes 430–432, 434, 436–438 or procedure codes for carotid revascularization (ICD 9 code 38.12) were considered. 
 
 Suspected CHD deaths were identified when ICD-9 codes 410–414 or 798 and 799 were reported as the underlying cause of death or codes 250, 401–405, 420–429 as the underlying cause of death, associated with codes 410–414 as a secondary cause of death. Suspected cerebrovascular deaths were identified when ICD-9 codes 430–438 were reported as the underlying, antecedent or direct cause of death. All events were validated using procedures of the American Heart Association (AHA), World Heart Federation (WHF), European Society of Cardiology (ESC), Centres for Disease Control (CDC) and National Heart, Lung, and Blood Institute (NHLBI) for epidemiology and clinical research studies.16 
 
 Ascertainment of risk factors at baseline 
 
 History of CVD included documented angina, myocardial infarction, revascularization procedures and cerebrovascular events. History of cancer included self-reported diagnosis of cancer. Hypertension was defined as systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mmHg or treatment for hypertension. Hypercholesterola emia was defined as total cholesterol ≥240 mg/dl or use of specific medication.17 Diabetes was defined as blood glucose ≥126 mg/dl or as specific pharmacological treatment. 
 
 Total physical activity was assessed by a structured questionnaire and expressed as daily energy expenditure in metabolic equivalent task-hours (MET-h/day). Body mass index (BMI) was calculated as kg/m2. Subjects were classified as never-smokers, current smokers or ex-smokers (having quitted for at least 1 year). 
 
 Socioeconomic indicators 
 
 Socioeconomic information was self-reported and collected by structured questionnaires administered by trained personnel. Detailed information on both education and household income are available; however, in this study, categories were chosen by taking into account the relatively low number of incident CVD events which do not permit consideration of these socioeconomic indicators in greater detail. Education was based on the highest qualification attained and was categorized as up to lower secondary (approximately ≤8 years of study), upper secondary education (≤13) and post-secondary or higher (>13). Household income, expressed as earned euros per year, was a four-level variable (<25 000; 25 000–40 000; >40 000 euro/year), with missing values collapsed into a non-respondent category. Marital status was considered as married/cohabiting, divorced/separated, single or widowed. 
 
 Dietary assessment and indices of diet quality 
 
 Food intake was assessed by the validated Italian EPIC food frequency questionnaire.18 Adherence to the MD was defined according to the Mediterranean Diet Score.7 
 
 Food antioxidant content (FAC) was appraised by a score determining the content in antioxidant vitamins and phytochemicals of each food group and ranged from −99 to 99, with higher values indicating increased consumption of foods rich in antioxidants.19 The polyphenol content of diet was measured by a polyphenol antioxidant content (PAC)-score calculated as in Pounis et al.20 Total antioxidant capacity of diet (TAC) was assessed as in Di Giuseppe et al.21 
 
 Variety of fruit and/or vegetable intake was assessed by four (fruit, vegetables, vegetables subgroups and fruit/vegetable combined) different diet diversity scores, following approaches similar to those tested within EPIC cohorts.22 Diversity was the total number of individual vegetable/fruit products eaten at least once in 2 weeks. Data on cooking procedures were collected for vegetables, meat and fish. A score was constructed to discriminate healthy (boiling, stewing) and hazardous (frying, roasting, grilling) cooking methods;23 the healthier the procedure, the higher the score. Organic food intake was limited to organic vegetables and categorized as yes/no. Whole-grain products consumption was restricted to whole-grain bread intake (yes/no). 
 
 Statistical analysis 
 
 Means with standard deviations (SDs) and percentages were used to describe the characteristics of the study population. Multivariable hazard ratios (HRs) with 95% confidence intervals (95% CIs) were calculated by using Cox proportional hazards models to analyse the association between adherence to the MD and incident vascular outcomes. The multivariable models were adjusted for sex, age, smoking status, education, household income, marital status, BMI (categorical), total physical activity (ordered quintiles), hypertension and/or hypercholesterolaemia at baseline, energy intake and consumption of eggs and potatoes. 
 
 Appropriate multiplicative terms for testing interaction of education and income with adherence to the MD, as measured as two-point increase in the MDS, were included in the multivariable models (alternately adjusted for education or income) to test for a difference of effect of the MD across SES strata. Analyses on income were run on 13 226 subjects after exclusion of the non-respondent category. Differences in diet-related indices or behaviours across SES strata were calculated only among individuals reporting high adherence to the MD (MDS ≥ 6). 
 
 Figure 1a and b shows differences in diet-related indices (highest vs lowest educational or income groups), divided by standard deviation of the difference. In these figures, individuals with intermediate educational or income values were eliminated. Dummy variables for missing values of each variable of interest were created. The data analysis was generated using SAS/STAT software, Version 9.4 of the SAS System for Windows©2010. SAS Institute Inc. and SAS are registered trademarks of SAS Institute Inc., Cary, NC, USA. 
 
 Figure 1 View largeDownload slide a. Mean differences in diet-related indices for highest vs lowest educational groups sharing similar adherence to the Mediterranean diet (MDS ≥ 6). Individuals with intermediate educational values were eliminated. Each difference was divided by its standard deviation. b. Mean differences in diet-related indices for highest vs lowest household income groups sharing similar adherence to the Mediterranean diet (MDS ≥ 6). Individuals with intermediate income values were eliminated. Each difference was divided by its standard deviation. 
 
 Figure 1 View largeDownload slide a. Mean differences in diet-related indices for highest vs lowest educational groups sharing similar adherence to the Mediterranean diet (MDS ≥ 6). Individuals with intermediate educational values were eliminated. Each difference was divided by its standard deviation. b. Mean differences in diet-related indices for highest vs lowest household income groups sharing similar adherence to the Mediterranean diet (MDS ≥ 6). Individuals with intermediate income values were eliminated. Each difference was divided by its standard deviation. 
 
 Results 
 
 Mediterranean diet and CVD risk 
 
 Over a median follow-up of 4.3 years (lower to upper quartile: 3.5–5.4; 82718 person-years), we ascertained a total of 256 CVD events of which were 207 CHD and 49 were strokes. Baseline characteristics of the study population according to adherence to the MD are presented in Table 1. 
 
 Table 1 Adherence to the Mediterranean diet Poor (0–3) Average (4–5) High (≥ 6) P-value N (%) 5812 (30.6) 8361 (44.0) 4818 (25.4) - Age (years, means ± SD) 52.4 (11.5) 54.4 (11.4) 56.0 (10.8) <0.0001 Sex (men, %) 41.1 44.2 49.7 0.92 Income (€/year; %) <0.0001 <25 000 34.2 36.3 35.4 25 000–40 000 19.7 21.7 23.2 >40 000 11.8 12.2 14.7 Non-respondents 34.2 29.8 26.7 Education (%) <0.0001 Up to lower secondary 50.2 50.2 48.6 Upper secondary 36.2 36.5 36.8 Post-secondary or higher 13.6 13.3 14.6 Marital status (%) <0.0001 Married/cohabiting 83.8 86.1 87.7 Separated/divorced 2.9 2.7 2.5 Single 6.3 5.4 4.6 Widowed 7.0 5.7 5.2 BMI (%) 0.027 Normal (<25) 32.3 29.2 28.8 Overweight (≥25 <30) 41.2 43.8 44.7 Obese (≥30) 26.5 27.0 26.5 Smokers (%) 24.4 24.0 23.0 0.0020 Total physical activity (means ± SD) 42.8 (8.1) 43.4 (8.6) 43.2 (8.6) 0.0004 Hypertension (%) 47.1 51.8 57.0 <0.0001 Hypercholesterolaemia (%) 27.4 27.5 32.0 0.0001 Cancer (%) 2.8 3.1 3.1 0.91 Aspirin use (%) 1.6 1.8 1.9 0.91 Blood glucose (mg/dl, means ± SD) 95.7 (11.5) 95.5 (11.6) 95.8 (11.5) 0.35 Energy intake (kcal/day, means ± SD) 1995 (531) 2094 (541) 2224 (517) <0.0001 Adherence to the Mediterranean diet Poor (0–3) Average (4–5) High (≥ 6) P-value N (%) 5812 (30.6) 8361 (44.0) 4818 (25.4) - Age (years, means ± SD) 52.4 (11.5) 54.4 (11.4) 56.0 (10.8) <0.0001 Sex (men, %) 41.1 44.2 49.7 0.92 Income (€/year; %) <0.0001 <25 000 34.2 36.3 35.4 25 000–40 000 19.7 21.7 23.2 >40 000 11.8 12.2 14.7 Non-respondents 34.2 29.8 26.7 Education (%) <0.0001 Up to lower secondary 50.2 50.2 48.6 Upper secondary 36.2 36.5 36.8 Post-secondary or higher 13.6 13.3 14.6 Marital status (%) <0.0001 Married/cohabiting 83.8 86.1 87.7 Separated/divorced 2.9 2.7 2.5 Single 6.3 5.4 4.6 Widowed 7.0 5.7 5.2 BMI (%) 0.027 Normal (<25) 32.3 29.2 28.8 Overweight (≥25 <30) 41.2 43.8 44.7 Obese (≥30) 26.5 27.0 26.5 Smokers (%) 24.4 24.0 23.0 0.0020 Total physical activity (means ± SD) 42.8 (8.1) 43.4 (8.6) 43.2 (8.6) 0.0004 Hypertension (%) 47.1 51.8 57.0 <0.0001 Hypercholesterolaemia (%) 27.4 27.5 32.0 0.0001 Cancer (%) 2.8 3.1 3.1 0.91 Aspirin use (%) 1.6 1.8 1.9 0.91 Blood glucose (mg/dl, means ± SD) 95.7 (11.5) 95.5 (11.6) 95.8 (11.5) 0.35 Energy intake (kcal/day, means ± SD) 1995 (531) 2094 (541) 2224 (517) <0.0001 
 
 Table 1 Adherence to the Mediterranean diet Poor (0–3) Average (4–5) High (≥ 6) P-value N (%) 5812 (30.6) 8361 (44.0) 4818 (25.4) - Age (years, means ± SD) 52.4 (11.5) 54.4 (11.4) 56.0 (10.8) <0.0001 Sex (men, %) 41.1 44.2 49.7 0.92 Income (€/year; %) <0.0001 <25 000 34.2 36.3 35.4 25 000–40 000 19.7 21.7 23.2 >40 000 11.8 12.2 14.7 Non-respondents 34.2 29.8 26.7 Education (%) <0.0001 Up to lower secondary 50.2 50.2 48.6 Upper secondary 36.2 36.5 36.8 Post-secondary or higher 13.6 13.3 14.6 Marital status (%) <0.0001 Married/cohabiting 83.8 86.1 87.7 Separated/divorced 2.9 2.7 2.5 Single 6.3 5.4 4.6 Widowed 7.0 5.7 5.2 BMI (%) 0.027 Normal (<25) 32.3 29.2 28.8 Overweight (≥25 <30) 41.2 43.8 44.7 Obese (≥30) 26.5 27.0 26.5 Smokers (%) 24.4 24.0 23.0 0.0020 Total physical activity (means ± SD) 42.8 (8.1) 43.4 (8.6) 43.2 (8.6) 0.0004 Hypertension (%) 47.1 51.8 57.0 <0.0001 Hypercholesterolaemia (%) 27.4 27.5 32.0 0.0001 Cancer (%) 2.8 3.1 3.1 0.91 Aspirin use (%) 1.6 1.8 1.9 0.91 Blood glucose (mg/dl, means ± SD) 95.7 (11.5) 95.5 (11.6) 95.8 (11.5) 0.35 Energy intake (kcal/day, means ± SD) 1995 (531) 2094 (541) 2224 (517) <0.0001 Adherence to the Mediterranean diet Poor (0–3) Average (4–5) High (≥ 6) P-value N (%) 5812 (30.6) 8361 (44.0) 4818 (25.4) - Age (years, means ± SD) 52.4 (11.5) 54.4 (11.4) 56.0 (10.8) <0.0001 Sex (men, %) 41.1 44.2 49.7 0.92 Income (€/year; %) <0.0001 <25 000 34.2 36.3 35.4 25 000–40 000 19.7 21.7 23.2 >40 000 11.8 12.2 14.7 Non-respondents 34.2 29.8 26.7 Education (%) <0.0001 Up to lower secondary 50.2 50.2 48.6 Upper secondary 36.2 36.5 36.8 Post-secondary or higher 13.6 13.3 14.6 Marital status (%) <0.0001 Married/cohabiting 83.8 86.1 87.7 Separated/divorced 2.9 2.7 2.5 Single 6.3 5.4 4.6 Widowed 7.0 5.7 5.2 BMI (%) 0.027 Normal (<25) 32.3 29.2 28.8 Overweight (≥25 <30) 41.2 43.8 44.7 Obese (≥30) 26.5 27.0 26.5 Smokers (%) 24.4 24.0 23.0 0.0020 Total physical activity (means ± SD) 42.8 (8.1) 43.4 (8.6) 43.2 (8.6) 0.0004 Hypertension (%) 47.1 51.8 57.0 <0.0001 Hypercholesterolaemia (%) 27.4 27.5 32.0 0.0001 Cancer (%) 2.8 3.1 3.1 0.91 Aspirin use (%) 1.6 1.8 1.9 0.91 Blood glucose (mg/dl, means ± SD) 95.7 (11.5) 95.5 (11.6) 95.8 (11.5) 0.35 Energy intake (kcal/day, means ± SD) 1995 (531) 2094 (541) 2224 (517) <0.0001 
 
 Highest adherence to the MD (MDS ≥ 6) was associated with reduced risk of CVD in the model controlled for age, sex and energy intake (Table 2) and also after further adjustment for a number of possible confounders (multivariable HR = 0.67; 95% CI: 0.48–0.94). A two-point increase in the MDS was also related to lower risk of CVD (multivariable HR = 0.85; 95% CI: 0.73–0.99; Figure 2). The association of the MD with CHD or stroke risk reflected a similar protective trend but results did not reach statistical significance (Table 2). 
 
 Table 2 Adherence to the traditional MD Two-point increase in MDS Poor (0–3) Average (4–5) High (≥6) N of subjects 5812 8361 4818 - CHD + Stroke (n = 256) N of events/rate 79 (1.36%) 109 (1.30%) 68 (1.41%) Person-years 24189 36319 22210 Model 1 (HR; 95% CI) -1‐ 0.78 (0.58–1.04) 0.70 (0.50–0.97) 0.87 (0.74–1.01) Model 2 (HR; 95% CI) ‐1‐ 0.75 (0.56–1.01) 0.67 (0.48–0.94) 0.85 (0.73–0.99) CHD (n = 207) N of events/rate 61 (1.05%) 90 (1.08%) 56 (1.16%) Person-years 24218 36344 22225 Model 1 (HR; 95% CI) ‐1‐ 0.83 (0.60–1.16) 0.75 (0.55–1.08) 0.89 (0.75–1.06) Model 2 (HR; 95% CI) ‐1‐ 0.80 (0.58–1.12) 0.71 (0.49–1.04) 0.87 (0.73–1.04) Stroke (n = 49) N of events/rate 18 (0.31%) 19 (0.23%) 12 (0.25%) Person-years 24303 36502 22309 Model 1 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.13) 0.54 (0.25–1.14) 0.78 (0.55–1.10) Model 2 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.14) 0.54 (0.25–1.16) 0.77 (0.54–1.11) Adherence to the traditional MD Two-point increase in MDS Poor (0–3) Average (4–5) High (≥6) N of subjects 5812 8361 4818 - CHD + Stroke (n = 256) N of events/rate 79 (1.36%) 109 (1.30%) 68 (1.41%) Person-years 24189 36319 22210 Model 1 (HR; 95% CI) -1‐ 0.78 (0.58–1.04) 0.70 (0.50–0.97) 0.87 (0.74–1.01) Model 2 (HR; 95% CI) ‐1‐ 0.75 (0.56–1.01) 0.67 (0.48–0.94) 0.85 (0.73–0.99) CHD (n = 207) N of events/rate 61 (1.05%) 90 (1.08%) 56 (1.16%) Person-years 24218 36344 22225 Model 1 (HR; 95% CI) ‐1‐ 0.83 (0.60–1.16) 0.75 (0.55–1.08) 0.89 (0.75–1.06) Model 2 (HR; 95% CI) ‐1‐ 0.80 (0.58–1.12) 0.71 (0.49–1.04) 0.87 (0.73–1.04) Stroke (n = 49) N of events/rate 18 (0.31%) 19 (0.23%) 12 (0.25%) Person-years 24303 36502 22309 Model 1 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.13) 0.54 (0.25–1.14) 0.78 (0.55–1.10) Model 2 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.14) 0.54 (0.25–1.16) 0.77 (0.54–1.11) 
 
 Table 2 Adherence to the traditional MD Two-point increase in MDS Poor (0–3) Average (4–5) High (≥6) N of subjects 5812 8361 4818 - CHD + Stroke (n = 256) N of events/rate 79 (1.36%) 109 (1.30%) 68 (1.41%) Person-years 24189 36319 22210 Model 1 (HR; 95% CI) -1‐ 0.78 (0.58–1.04) 0.70 (0.50–0.97) 0.87 (0.74–1.01) Model 2 (HR; 95% CI) ‐1‐ 0.75 (0.56–1.01) 0.67 (0.48–0.94) 0.85 (0.73–0.99) CHD (n = 207) N of events/rate 61 (1.05%) 90 (1.08%) 56 (1.16%) Person-years 24218 36344 22225 Model 1 (HR; 95% CI) ‐1‐ 0.83 (0.60–1.16) 0.75 (0.55–1.08) 0.89 (0.75–1.06) Model 2 (HR; 95% CI) ‐1‐ 0.80 (0.58–1.12) 0.71 (0.49–1.04) 0.87 (0.73–1.04) Stroke (n = 49) N of events/rate 18 (0.31%) 19 (0.23%) 12 (0.25%) Person-years 24303 36502 22309 Model 1 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.13) 0.54 (0.25–1.14) 0.78 (0.55–1.10) Model 2 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.14) 0.54 (0.25–1.16) 0.77 (0.54–1.11) Adherence to the traditional MD Two-point increase in MDS Poor (0–3) Average (4–5) High (≥6) N of subjects 5812 8361 4818 - CHD + Stroke (n = 256) N of events/rate 79 (1.36%) 109 (1.30%) 68 (1.41%) Person-years 24189 36319 22210 Model 1 (HR; 95% CI) -1‐ 0.78 (0.58–1.04) 0.70 (0.50–0.97) 0.87 (0.74–1.01) Model 2 (HR; 95% CI) ‐1‐ 0.75 (0.56–1.01) 0.67 (0.48–0.94) 0.85 (0.73–0.99) CHD (n = 207) N of events/rate 61 (1.05%) 90 (1.08%) 56 (1.16%) Person-years 24218 36344 22225 Model 1 (HR; 95% CI) ‐1‐ 0.83 (0.60–1.16) 0.75 (0.55–1.08) 0.89 (0.75–1.06) Model 2 (HR; 95% CI) ‐1‐ 0.80 (0.58–1.12) 0.71 (0.49–1.04) 0.87 (0.73–1.04) Stroke (n = 49) N of events/rate 18 (0.31%) 19 (0.23%) 12 (0.25%) Person-years 24303 36502 22309 Model 1 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.13) 0.54 (0.25–1.14) 0.78 (0.55–1.10) Model 2 (HR; 95% CI) ‐1‐ 0.59 (0.31–1.14) 0.54 (0.25–1.16) 0.77 (0.54–1.11) 
 
 Figure 2 View largeDownload slide Cardiovascular risk (hazard ratio with 95% confidence intervals) associated with two-point increment in the MDS in the whole study population and across educational and household income groups. 
 
 Figure 2 View largeDownload slide Cardiovascular risk (hazard ratio with 95% confidence intervals) associated with two-point increment in the MDS in the whole study population and across educational and household income groups. 
 
 Mediterranean diet and CVD risk in socioeconomic strata 
 
 A likely different association of the MD, expressed as two-point increase in the MDS, with CVD risk across SES strata was tested by including two separate terms of interaction (educationMDS or incomeMDS) in the multivariable model further controlled for education or income; the P-value for interaction for education was 0.042 and for household income was 0.0098 (Figure 2). A two-point increment in the MDS was associated with lower CVD risk only in the group with a post-secondary education, in a model further controlled for income levels (HR = 0.43; 95% CI: 0.25–0.72), and no relationship was found for those with lower education (HR = 0.94; 95% CI: 0.78–1.14; Table 3). Similarly, the protection from an MD was only evident in the group with higher household income (HR = 0.39; 95% CI: 0.23–0.66 vs HR = 1.01; 95% CI: 0.79–1.29 of the lowest household income group; Table 3). 
 
 Table 3 Educational level Up to lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Postgraduate-higher (>13 years) P for interaction N of CVD events/n of subjects 170/9457 63/6926 23/2608 0.042 Event rate (%) 1.80 0.92 0.88 CVD risk (HR; 95% CIa 0.94 (0.78–1.14) 0.80 (0.58–1.10) 0.43 (0.25–0.72) Household income groups (€/year)b <25 000 25 000–40 000 >40 000 P for interaction N of CVD events/n of subjects 101/6730 47/4080 27/2416 0.0098 Event rate (%) 1.50 1.15 1.10 CVD risk (HR; 95% CI)a 1.01 (0.79–1.29) 1.00 (0.69–1.46) 0.39 (0.23–0.66) Educational level Up to lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Postgraduate-higher (>13 years) P for interaction N of CVD events/n of subjects 170/9457 63/6926 23/2608 0.042 Event rate (%) 1.80 0.92 0.88 CVD risk (HR; 95% CIa 0.94 (0.78–1.14) 0.80 (0.58–1.10) 0.43 (0.25–0.72) Household income groups (€/year)b <25 000 25 000–40 000 >40 000 P for interaction N of CVD events/n of subjects 101/6730 47/4080 27/2416 0.0098 Event rate (%) 1.50 1.15 1.10 CVD risk (HR; 95% CI)a 1.01 (0.79–1.29) 1.00 (0.69–1.46) 0.39 (0.23–0.66) 
 
 Table 3 Educational level Up to lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Postgraduate-higher (>13 years) P for interaction N of CVD events/n of subjects 170/9457 63/6926 23/2608 0.042 Event rate (%) 1.80 0.92 0.88 CVD risk (HR; 95% CIa 0.94 (0.78–1.14) 0.80 (0.58–1.10) 0.43 (0.25–0.72) Household income groups (€/year)b <25 000 25 000–40 000 >40 000 P for interaction N of CVD events/n of subjects 101/6730 47/4080 27/2416 0.0098 Event rate (%) 1.50 1.15 1.10 CVD risk (HR; 95% CI)a 1.01 (0.79–1.29) 1.00 (0.69–1.46) 0.39 (0.23–0.66) Educational level Up to lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Postgraduate-higher (>13 years) P for interaction N of CVD events/n of subjects 170/9457 63/6926 23/2608 0.042 Event rate (%) 1.80 0.92 0.88 CVD risk (HR; 95% CIa 0.94 (0.78–1.14) 0.80 (0.58–1.10) 0.43 (0.25–0.72) Household income groups (€/year)b <25 000 25 000–40 000 >40 000 P for interaction N of CVD events/n of subjects 101/6730 47/4080 27/2416 0.0098 Event rate (%) 1.50 1.15 1.10 CVD risk (HR; 95% CI)a 1.01 (0.79–1.29) 1.00 (0.69–1.46) 0.39 (0.23–0.66) 
 
 Indices of diet quality and diet-related behaviours across SES groups 
 
 In order to understand why CVD protection was confined to high-SES individuals, we examined possible gaps (as measured by additional indicators of diet quality or dietary behaviours) still persisting among SES groups sharing similar adherence to the MD (MDS ≥ 6). In the multivariable model additionally controlled for the MDS, educational groups still differed for some diet-related indicators such as diet variety for vegetables and vegetable subgroups that were all higher in highly educated as compared with less educated subjects (Table 4; Figure 1a). Subjects with post-secondary education also reported increased intake of organic vegetables and whole-grain bread as well as higher daily intake of mono-unsaturated and saturated fatty acids, vitamin D, calcium and fibre (Figure 1a). No difference was recorded for any of the indicators used to assess dietary antioxidant or polyphenol content or total antioxidant capacity of the diet, and disparities in cooking methods were limited to vegetable preparation that was healthier in those with higher education (Table 4). In addition, highly educated subjects were more likely to report higher fish intake and low meat/meat products consumption but less likely to report low intake of dairy products (Supplementary Table 5A, available as Supplementary data at IJE online). Dietary intake of polyphenols, antioxidants, fibre and indicators of TAC were all increased in the higher income group as compared with the lowest. Greater income was also associated with increased prevalence of whole-grain bread consumption, and the diversity in vegetable and fruit intake was slightly higher in the lowest income group along with daily intake of MUFAs and PUFAs (Table 4; Figure 1b). Differences in cooking procedures were identified for healthier methods in preparing vegetables but more hazardous procedures for meat (Table 4). Individuals with greater income reported higher consumption of fruits and nuts and fish, and lower intake of meat and meat products (Supplementary table 5B). 
 
 Table 4 Educational level Household income groups (€/year) Lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Post-secondary/ higher (>13 years) P for trend <25 000 25 000– 40 000 >40 000 P for trend N of subjects 2340 1773 705 1706 1118 706 Food antioxidant content (score) 33 (39) 34 (38) 35 (38) 0.69 33 (40) 35 (37) 37 (38) 0.015 Polyphenols intake (score) 8.4 (10.7) 9.1 (10.7) 9.4 (10.7) 0.12 8 (11) 8 (10) 10 (11) 0.031 TEAC 6.6 (2.7) 6.7 (2.5) 6.8 (2.3) 0.38 6.6 (2.6) 6.7 (2.5) 7.0 (2.5) 0.054 TRAP 9.4 (4.1) 9.6 (4.0) 9.7 (3.5) 0.47 9.5 (4.1) 9.7 (3.9) 10.1 (4.0) 0.033 FRAP 19.7 (8.0) 20.2 (7.8) 20.4 (6.8) 0.25 20.0 (8.0) 20.2 (7.6) 21.1 (7.7) 0.030 MUFAs 39.9 (10.7) 40.0 (10.4) 40.2 (10.7) 0.034 8.9 (2.4) 8.9 (2.3) 8.8 (2.3) 0.99 PUFAs 8.7 (2.4) 8.7 (2.3) 8.7 (2.3) 0.38 40.6 (11.0) 40.9 (10.5) 39.8 (10.2) 0.13 SFAs 26.2 (8.6) 26.8 (8.8) 27.0 (8.9) <.0001 8.9 (2.5) 8.8 (2.3) 8.7 (2.2) 0.040 Dietary vitamin D 2.47 (0.98) 2.61 (1.00) 2.64 (1.06) <.0001 26.7 (8.7) 27.2 (8.8) 26.3 (8.9) 0.46 Dietary calcium 901 (290) 945 (311) 960 (317) <.0001 2.51 (0.99) 2.61 (1.02) 2.61 (1.02) 0.25 Dietary fibre 24.3 (6.7) 24.8 (6.8) 25.1 (7.1) 0.12 924 (297) 954 (307) 953 (322) 0.38 Diet diversity fruits (score) 8.9 (2.4) 8.8 (2.4) 8.8 (2.4) 0.15 24.5 (7.1) 24.6 (6.7) 25.9 (7.1) 0.0008 Diet diversity vegetables (score) 7.1 (2.4) 7.2 (2.5) 7.2 (2.5) 0.0005 7.3 (2.4) 7.2 (2.5) 6.9 (2.5) < 0.0001 Diet diversity vegetables subgroup (score) 4.20 (1.05) 4.20 (1.08) 4.23 (1.08) 0.016 4.2 (1.1) 4.2 (1.1) 4.2 (1.1) 0.34 Diet diversity fruit and veg (score) 16 (3.6) 15.9 (3.7) 15.9 (3.6) 0.15 16.2 (3.7) 16.1 (3.6) 15.7 (3.7) 0.0068 Organic vegetables consumers (%) 1.9 2.7 5.1 0.0047 2.2 2.3 4.7 0.08 Whole-grain bread consumers (%) 13.4 18.7 25.4 <.0001 13.8 19.0 21.8 0.018 Educational level Household income groups (€/year) Lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Post-secondary/ higher (>13 years) P for trend <25 000 25 000– 40 000 >40 000 P for trend N of subjects 2340 1773 705 1706 1118 706 Food antioxidant content (score) 33 (39) 34 (38) 35 (38) 0.69 33 (40) 35 (37) 37 (38) 0.015 Polyphenols intake (score) 8.4 (10.7) 9.1 (10.7) 9.4 (10.7) 0.12 8 (11) 8 (10) 10 (11) 0.031 TEAC 6.6 (2.7) 6.7 (2.5) 6.8 (2.3) 0.38 6.6 (2.6) 6.7 (2.5) 7.0 (2.5) 0.054 TRAP 9.4 (4.1) 9.6 (4.0) 9.7 (3.5) 0.47 9.5 (4.1) 9.7 (3.9) 10.1 (4.0) 0.033 FRAP 19.7 (8.0) 20.2 (7.8) 20.4 (6.8) 0.25 20.0 (8.0) 20.2 (7.6) 21.1 (7.7) 0.030 MUFAs 39.9 (10.7) 40.0 (10.4) 40.2 (10.7) 0.034 8.9 (2.4) 8.9 (2.3) 8.8 (2.3) 0.99 PUFAs 8.7 (2.4) 8.7 (2.3) 8.7 (2.3) 0.38 40.6 (11.0) 40.9 (10.5) 39.8 (10.2) 0.13 SFAs 26.2 (8.6) 26.8 (8.8) 27.0 (8.9) <.0001 8.9 (2.5) 8.8 (2.3) 8.7 (2.2) 0.040 Dietary vitamin D 2.47 (0.98) 2.61 (1.00) 2.64 (1.06) <.0001 26.7 (8.7) 27.2 (8.8) 26.3 (8.9) 0.46 Dietary calcium 901 (290) 945 (311) 960 (317) <.0001 2.51 (0.99) 2.61 (1.02) 2.61 (1.02) 0.25 Dietary fibre 24.3 (6.7) 24.8 (6.8) 25.1 (7.1) 0.12 924 (297) 954 (307) 953 (322) 0.38 Diet diversity fruits (score) 8.9 (2.4) 8.8 (2.4) 8.8 (2.4) 0.15 24.5 (7.1) 24.6 (6.7) 25.9 (7.1) 0.0008 Diet diversity vegetables (score) 7.1 (2.4) 7.2 (2.5) 7.2 (2.5) 0.0005 7.3 (2.4) 7.2 (2.5) 6.9 (2.5) < 0.0001 Diet diversity vegetables subgroup (score) 4.20 (1.05) 4.20 (1.08) 4.23 (1.08) 0.016 4.2 (1.1) 4.2 (1.1) 4.2 (1.1) 0.34 Diet diversity fruit and veg (score) 16 (3.6) 15.9 (3.7) 15.9 (3.6) 0.15 16.2 (3.7) 16.1 (3.6) 15.7 (3.7) 0.0068 Organic vegetables consumers (%) 1.9 2.7 5.1 0.0047 2.2 2.3 4.7 0.08 Whole-grain bread consumers (%) 13.4 18.7 25.4 <.0001 13.8 19.0 21.8 0.018 
 
 Table 4 Educational level Household income groups (€/year) Lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Post-secondary/ higher (>13 years) P for trend <25 000 25 000– 40 000 >40 000 P for trend N of subjects 2340 1773 705 1706 1118 706 Food antioxidant content (score) 33 (39) 34 (38) 35 (38) 0.69 33 (40) 35 (37) 37 (38) 0.015 Polyphenols intake (score) 8.4 (10.7) 9.1 (10.7) 9.4 (10.7) 0.12 8 (11) 8 (10) 10 (11) 0.031 TEAC 6.6 (2.7) 6.7 (2.5) 6.8 (2.3) 0.38 6.6 (2.6) 6.7 (2.5) 7.0 (2.5) 0.054 TRAP 9.4 (4.1) 9.6 (4.0) 9.7 (3.5) 0.47 9.5 (4.1) 9.7 (3.9) 10.1 (4.0) 0.033 FRAP 19.7 (8.0) 20.2 (7.8) 20.4 (6.8) 0.25 20.0 (8.0) 20.2 (7.6) 21.1 (7.7) 0.030 MUFAs 39.9 (10.7) 40.0 (10.4) 40.2 (10.7) 0.034 8.9 (2.4) 8.9 (2.3) 8.8 (2.3) 0.99 PUFAs 8.7 (2.4) 8.7 (2.3) 8.7 (2.3) 0.38 40.6 (11.0) 40.9 (10.5) 39.8 (10.2) 0.13 SFAs 26.2 (8.6) 26.8 (8.8) 27.0 (8.9) <.0001 8.9 (2.5) 8.8 (2.3) 8.7 (2.2) 0.040 Dietary vitamin D 2.47 (0.98) 2.61 (1.00) 2.64 (1.06) <.0001 26.7 (8.7) 27.2 (8.8) 26.3 (8.9) 0.46 Dietary calcium 901 (290) 945 (311) 960 (317) <.0001 2.51 (0.99) 2.61 (1.02) 2.61 (1.02) 0.25 Dietary fibre 24.3 (6.7) 24.8 (6.8) 25.1 (7.1) 0.12 924 (297) 954 (307) 953 (322) 0.38 Diet diversity fruits (score) 8.9 (2.4) 8.8 (2.4) 8.8 (2.4) 0.15 24.5 (7.1) 24.6 (6.7) 25.9 (7.1) 0.0008 Diet diversity vegetables (score) 7.1 (2.4) 7.2 (2.5) 7.2 (2.5) 0.0005 7.3 (2.4) 7.2 (2.5) 6.9 (2.5) < 0.0001 Diet diversity vegetables subgroup (score) 4.20 (1.05) 4.20 (1.08) 4.23 (1.08) 0.016 4.2 (1.1) 4.2 (1.1) 4.2 (1.1) 0.34 Diet diversity fruit and veg (score) 16 (3.6) 15.9 (3.7) 15.9 (3.6) 0.15 16.2 (3.7) 16.1 (3.6) 15.7 (3.7) 0.0068 Organic vegetables consumers (%) 1.9 2.7 5.1 0.0047 2.2 2.3 4.7 0.08 Whole-grain bread consumers (%) 13.4 18.7 25.4 <.0001 13.8 19.0 21.8 0.018 Educational level Household income groups (€/year) Lower secondary (≤8 years) Upper secondary (>8 ≤ 13 years) Post-secondary/ higher (>13 years) P for trend <25 000 25 000– 40 000 >40 000 P for trend N of subjects 2340 1773 705 1706 1118 706 Food antioxidant content (score) 33 (39) 34 (38) 35 (38) 0.69 33 (40) 35 (37) 37 (38) 0.015 Polyphenols intake (score) 8.4 (10.7) 9.1 (10.7) 9.4 (10.7) 0.12 8 (11) 8 (10) 10 (11) 0.031 TEAC 6.6 (2.7) 6.7 (2.5) 6.8 (2.3) 0.38 6.6 (2.6) 6.7 (2.5) 7.0 (2.5) 0.054 TRAP 9.4 (4.1) 9.6 (4.0) 9.7 (3.5) 0.47 9.5 (4.1) 9.7 (3.9) 10.1 (4.0) 0.033 FRAP 19.7 (8.0) 20.2 (7.8) 20.4 (6.8) 0.25 20.0 (8.0) 20.2 (7.6) 21.1 (7.7) 0.030 MUFAs 39.9 (10.7) 40.0 (10.4) 40.2 (10.7) 0.034 8.9 (2.4) 8.9 (2.3) 8.8 (2.3) 0.99 PUFAs 8.7 (2.4) 8.7 (2.3) 8.7 (2.3) 0.38 40.6 (11.0) 40.9 (10.5) 39.8 (10.2) 0.13 SFAs 26.2 (8.6) 26.8 (8.8) 27.0 (8.9) <.0001 8.9 (2.5) 8.8 (2.3) 8.7 (2.2) 0.040 Dietary vitamin D 2.47 (0.98) 2.61 (1.00) 2.64 (1.06) <.0001 26.7 (8.7) 27.2 (8.8) 26.3 (8.9) 0.46 Dietary calcium 901 (290) 945 (311) 960 (317) <.0001 2.51 (0.99) 2.61 (1.02) 2.61 (1.02) 0.25 Dietary fibre 24.3 (6.7) 24.8 (6.8) 25.1 (7.1) 0.12 924 (297) 954 (307) 953 (322) 0.38 Diet diversity fruits (score) 8.9 (2.4) 8.8 (2.4) 8.8 (2.4) 0.15 24.5 (7.1) 24.6 (6.7) 25.9 (7.1) 0.0008 Diet diversity vegetables (score) 7.1 (2.4) 7.2 (2.5) 7.2 (2.5) 0.0005 7.3 (2.4) 7.2 (2.5) 6.9 (2.5) < 0.0001 Diet diversity vegetables subgroup (score) 4.20 (1.05) 4.20 (1.08) 4.23 (1.08) 0.016 4.2 (1.1) 4.2 (1.1) 4.2 (1.1) 0.34 Diet diversity fruit and veg (score) 16 (3.6) 15.9 (3.7) 15.9 (3.6) 0.15 16.2 (3.7) 16.1 (3.6) 15.7 (3.7) 0.0068 Organic vegetables consumers (%) 1.9 2.7 5.1 0.0047 2.2 2.3 4.7 0.08 Whole-grain bread consumers (%) 13.4 18.7 25.4 <.0001 13.8 19.0 21.8 0.018 
 
 Discussion 
 
 In this large community-based Mediterranean population, higher adherence to MD was associated with lower risk of CVD in line with previous evidence.2,3,24 However, this relationship was confined in fact to high-SES groups. Specifically, a two-point increase in the MDS was associated with 57% lower risk of CVD for subjects with post-secondary education, or 61% lower risk in the highest category of household income, whereas no relationship was found for less educated groups or in the lower income categories. 
 
 To the best of our knowledge, this is the first study to show that the association between Mediterranean diet and CVD risk differs across SES groups. 
 
 Socioeconomic disparities in the composition of similar MDS 
 
 Given a comparable score of adherence to MD, both higher educational and higher income groups were more frequently found to consume higher intake of fish and lower amounts of meat. Many studies have documented the important role of the above-mentioned food groups in promoting favourable health effects25 and reducing main CVD risk factors.26 However, whether higher fish consumption and limited meat intake may contribute to the different CVD risk reduction across SES groups remain to be ascertained. 
 
 Socioeconomic disparities in nutrients and diet-related behaviours 
 
 Despite similar score of adherence to MD, post-secondary education was associated with higher diet variety for vegetables and vegetables subgroups, and with preference for whole-grain bread. Such educational gradient in food selection is in agreement with previous evidence indicating that higher SES groups are more likely to get in line with dietary recommendations.27 High education was also related to greater consumption of organic vegetables, which has been previously shown to be strongly determined by SES,13,28 although there is uncertainty on the actual health advantages deriving from organic food consumption.29 Educational disparities emerged also for MUFAs, dietary vitamin D, calcium and fibre, whose higher intake is associated with more favourable cardiovascular health. We also found differences across income groups sharing similar scores of adherence to the MD for dietary polyphenol and antioxidant intake, total antioxidant capacity of the diet, and preference for whole-grain bread. 
 
 For both high-education and high-income individuals, disparities in food preparation were limited to healthier cooking methods for vegetables, which are possibly associated with increased overall antioxidant content.14 Of note, high income was also associated with more hazardous cooking methods for beef (frying, roasting, grilling), and such high-temperature cooking techniques are more likely to propagate and accelerate formation of pro-inflammatory compounds associated with increased CVD risk.23,30 
 
 There are many studies indicating potential health benefits for each of these diet-related indices that in our study were found to vary consistently among SES groups, net of adherence to the MD. As highlighted in previous research, the nutritional properties of foods are closely dependent on external influences such as food processing and cooking procedures.14 Foods that are not discriminated in epidemiological studies may substantially differ in their bioactive compounds content, with different health outcomes.14 In our study, we also found that higher-SES subjects tend to consume more organic vegetables which can contain higher concentrations of antioxidants, lower concentrations of cadmium and a lower incidence of pesticide residues,29 as compared with conventionally grown foods. We might then speculate that the quality of the bundle of foods that make up the MD actually differs across SES. 
 
 Unfortunately, our data derive from self-reported dietary intakes, thus we are not able to unequivocally establish whether, given apparently similar adherence to an MD, high-SES groups actually select foods higher in polyphenols or antioxidants compounds that would result in future health advantages. This hypothesis could be only tested by a direct measure of such natural compounds in biological samples. 
 
 On the basis of our results and by accounting for all the limitations inherent to our approach, we suggest that at comparable levels of adherence to the MD, higher SES groups actually select foods with increased nutritional value as those higher in antioxidant content or capacity, and are more keen on reporting a larger variety in fruit and vegetable consumption, thus obtaining more adequate intake of essential nutrients. Such nutritional gaps may partly explain the observed socioeconomic pattern of protection derived from apparently similar scores of adherence to the MD. Of note, the interaction between diet and SES on CVD health outcomes was found both for cultural (education) and financial resources (income), likely indicating that healthier choices are driven either by a good set of knowledge and skills or greater financial resources. 
 
 In light of our findings, we speculate that standard dietary scores, although useful and valid parameters to quantify the adherence to the Mediterranean diet, may not fully capture the complexity of this diet, leaving out a number of additional dietary details mainly related to the quality of the products. If so, we would be dealing with a methodological limitation which may be overcome by the use of other tools to better appraise the dietary behaviours of a given population. 
 
 Strengths and limitations of this study 
 
 Major strengths of the present study include the large sample size, prospective study design, large number of indices of diet quality and diet-related behaviours, and comprehensive information on covariates, thus minimizing sources of bias and confounding. 
 
 Some potential limitations include the relatively short follow-up (and the consequent low number of events) and the observational nature of the study, which cannot fully rule out residual confounding. In addition, dietary data were based on self-reported information and therefore may be susceptible to error and bias. Moreover, although we tested a large number of indices for assessing diet beyond the MD, we are aware that several nutritional details may remain unaddressed, i.e. organic foods other than vegetables, and food purchasing behaviours consistent with dietary guideline recommendations. Finally, subjects’ information was collected at baseline only; thus, life course changes possibly occurring during follow-up may influence the strength of the findings. 
 
 Conclusions 
 
 To the best of our knowledge, this large epidemiological study in a population-based cohort is the first to shed light on SES inequities in the cardiovascular protection associated with a traditional Mediterranean diet. From a public health perspective, these results support the need to adopt more effective strategies aiming to reduce socioeconomic disparities in health, not only by promoting the adoption of healthy eating patterns but also by facilitating access to foods with higher nutritional values likely associated with improved health outcomes. 
 
 Supplementary Data 
 
 Supplementary data are available at IJE online. 
 
 Funding 
 
 The enrolment phase of the Moli-sani Study was supported by research grants from the Pfizer Foundation (Rome, Italy), the Italian Ministry of University and Research (MIUR, Rome, Italy)–Programma Triennale di Ricerca, Decreto no.1588 and Instrumentation Laboratory, Milan, Italy. M.B. was supported by a Fondazione Umberto Veronesi Fellowship. The present analyses were partially supported by the Italian Ministry of Health [Grant number GR-2013‐02356060]. Funders had no role in study design; collection, analysis or interpretation of data; the writing of the manuscript; or the decision to submit the article for publication. 
 
 Key Messages Adherence to the Mediterranean diet is inversely associated with cardiovascular risk. 
 
 Cardiovascular advantages associated with the Mediterranean diet are confined to high socioeconomic status individuals. 
 
 In groups sharing similar adherence to the Mediterranean diet, inequities in diet-related behaviours and nutrient intake still persist. 
 
 Acknowledgements 
 
 The Moli-sani research group thanks the Associazione Cuore Sano Onlus (Campobasso, Italy) for its financial and cultural support. 
 
 Author Contributions 
 
 M.B., L.I. and A.D.C. contributed to the concept and design of the work and interpretation of data; S.C., M.P. and G.P. managed data collection; M.B. and A.D.C. analysed the data; M.B. wrote the paper; M.B.D., C.C., G.d.G. and L.I. originally inspired the research and critically reviewed the manuscript. 
 
 Conflict of interest: None of the authors had a personal or financial conflict of interest. All authors were and are independent from funders. 
 
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 Jeff Lagerquist, CTVNews.ca 
 
 
 
 
 
 Choosing a Mediterranean diet has long been linked to a bevy of health benefits, including reduced risk of heart disease and lower rates of cancer. But new research shows if you are going to mimic the eating habits of someone who hails from the region, you had better make sure they are rich and highly educated. 
 
 Mainstays of the Mediterranean diet include a high intake of vegetables, legumes, fruits, nuts and unrefined cereals, as well as plenty of olive oil, moderate intake of fish, and low-to-moderate dairy, low red meat and poultry, and moderate wine consumption, according to a 2003 study published in the New England Journal of Medicine. 
 
 A new Italian study led by a team of researchers at IRCCS Neuromed looked at the dietary information of 18,991 southern Italian men and women over 35 between March 2005 and April 2010. 
 
 The sample group did not include individuals with a history of cardiovascular disease, diabetes, inordinately high or low calorie intakes, or incomplete personal data. 
 
 Socioeconomic information and food intake statistics were collected through questionnaires. The researchers measured factors such as food antioxidant content, variety of fruits and vegetable intake, health of cooking practices (boiling, frying, roasting, grilling), organic food intake, and consumption of whole grain products. 
 
 Overall adherence to the Mediterranean diet was given a score measured against the definition outlined by the 2003 New England Journal of Medicine study. 
 
 More than 250 cardiovascular disease events were recorded over a median follow-up period of 4.3 years. 
 
 Overall, a two-point increase in participants’ Mediterranean diet scores resulted in a 15 per cent decline in cardiovascular disease risk. 
 
 But that benefit did not materialize for less educated subjects. Similarly, the cardiovascular disease fighting benefits were confined to the high-income households, compared to lower-earning peers. 
 
 “Given a comparable adherence to this eating pattern, the study has shown that the reduction in cardiovascular risk is observed only in people with a higher educational level and/or greater household income. No actual benefits were observed for the less advantaged groups,” said the study’s authors in a release accompanying the study. 
 
 The cardiovascular disease findings are even more striking when high education, high income individuals are observed in isolation. 
 
 The study notes a two-point increase in the Mediterranean diet score drops cardiovascular disease risk by 57 per cent among those with post-secondary education, and 61 per cent for those in the highest category of household income. 
 
 Once again, no such relationship was observed among the less educated and less wealthy. 
 
 The difference comes down to “different intakes of antioxidants and polyphenols, fatty acids, micronutrients, dietary antioxidant capacity, dietary diversity, organic vegetables and whole grain bread consumption,” according to the study. 
 
 The more highly educated subjects were found to eat a wider variety of vegetables, more organic produce, and whole grain breads. They also opted for higher fish intake versus meat consumption. Greater income was also associated with eating more fruits, nuts and fish, and eating fewer meat products. 
 
 The study’s authors admit the limitations of self-reported dietary intake profiles means the research falls short of establishing a direct link between better-heeled groups and the selection of more nutritious food. However, they suggest their findings make a strong case for further investigation of into the role of income and education on diet-based health outcomes. 
 
 “Socioeconomic disparities in health are growing, also in access to healthy diets,” wrote IRCCS Department of Epidemiology and Prevention head Giovanni de Gaetano. “We cannot be keeping on saying that the Mediterranean diet is good for health if we are not able to guarantee an equal access to it.” 
 
 The findings were based on subjects within the Moli-sani study, which has examined environmental and genetic factors underlying cardiovascular disease, cancer, and degenerative pathologies for the past 12 years. 
 
 The research has been published in the International Journal of Epidemiology. 

 The Mediterranean diet reduces the risk of cardiovascular disease but only if you are rich or highly educated. This is the surprising finding by researchers from the Italian I.R.C.C.S. Neuromed, who performed a study on over 18,000 subjects recruited within the Moli-sani study and published in the International Journal of Epidemiology. 
 
 Cardiovascular advantages associated with the Mediterranean diet are well-known but now the Italian study, conducted by a team of researchers at the Department of Epidemiology and Prevention led by Giovanni de Gaetano, reveals that such benefits are strongly influenced by the socioeconomic position of people. Basically, given a comparable adherence to this eating pattern, the study has shown that the reduction in cardiovascular risk is observed only in people with higher educational level and/or greater household income. No actual benefits were observed for the less advantaged groups. 
 
 "The cardiovascular benefits associated with the Mediterranean diet in a general population are well known -- says Marialaura Bonaccio, researcher at the Department of Epidemiology and Prevention and first author of the study -- Yet for the first time our study has revealed that the socioeconomic position is able to modulate the health advantages linked to Mediterranean diet. In other words, a person from low socioeconomic status who struggles to follow a Mediterranean model, is unlikely to get the same advantages of a person with higher income, despite the fact that they both similarly adhere to the same healthy diet". 
 
 Neuromed researchers went further and tried to unravel the possible mechanisms underlying such disparities. 
 
 "Given a comparable adherence to the Mediterranean diet, the most advantaged groups were more likely to report a larger number of indices of high quality diet as opposed to people with low socioeconomic status -- explains Licia Iacoviello, head of the Laboratory of nutritional and molecular Epidemiology at the Department -- For example, within those reporting an optimal adherence to the Mediterranean diet (as measured by a score comprising fruits and nuts, vegetables, legumes, cereals, fish, fats, meat, dairy products and alcohol intake) people with high income or higher educational level consumed products richer in antioxidants and polyphenols, and had a greater diversity in fruit and vegetables choice. We have also found a socioeconomic gradient in the consumption of whole-grain products and in the preferred cooking methods. These substantial differences in consuming products belonging to Mediterranean diet lead us to think that quality of foods may be as important for health as quantity and frequency of intake". 
 
 "Our results should promote a serious consideration of socioeconomic scenario of health - comments Giovanni de Gaetano, director of the Department -- Socioeconomic disparities in health are growing also in access to healthy diets. During the very last years, we documented a rapid shifting from the Mediterranean diet in the whole population, but it might also be that the weakest citizens tend to buy 'Mediterranean' food with lower nutritional value. We cannot be keeping on say that the Mediterranean diet is good for health -- de Gaetano concludes -- if we are not able to guarantee an equal access to it". 
 
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 The Moli-sani Project 
 
 Started in March 2005, it involves about 25,000 citizens living in the Molise region. The aim is to learn about environmental and genetic factors underlying cardiovascular disease, cancer and degenerative pathologies. Moli-sani study, now based in I.R.C.C.S. Neuromed, has transformed an entire Italian region in a large research lab. 
 
 The I.R.C.C.S. Neuromed 
 
 The Institute for Research, Hospitalization and Health Care (I.R.C.C.S.) Neuromed in Pozzilli (Italy) is a landmark, at Italian and international level, for research and therapy in the field of nervous system diseases. A center in which doctors, researchers, staff and the patients themselves form an alliance aimed at ensuring the best level of service and cutting-edge treatments, guided by the most advanced scientific developments.
– Despite its many purported advantages, the Mediterranean diet might not be all it's cracked up to be. According to a new study in the International Journal of Epidemiology, its effects depend largely on socioeconomic status. Researchers surveyed 19,000 people ages 35 and over in Italy, giving each a score based on how closely they followed the Mediterranean diet, ranging from 1 on the low end up to 6 or more. After just over four years, they found a two-point increase in score meant a 15% reduced risk of cardiovascular disease overall—but not for participants with low incomes and minimal education. While a two-point increase meant a reduced risk of 61% for those with a household income of at least $47,000, and 57% for those with post-secondary education, "no actual benefits were observed for the less advantaged groups," per a release. Despite similar adherence to the diet, that remained the case after researchers accounted for healthy habits common among the rich, like getting plenty of exercise, avoiding smoking, and making regular visits to the doctor, per HealthDay News. Researchers suspect that's because people with higher education or income tended to eat a greater variety of foods, as well as more whole grains, organic produce, and fish, which can be expensive, per CTV News. They also prepared vegetables in healthier ways. Together, this means they benefited from a "more adequate intake of essential nutrients," says study author Giovanni de Gaetano. He suggests experts should stop promoting the diet "if we are not able to guarantee an equal access to it." (Read about its brain benefits here.)