The Mediterranean diet — rich in vegetables, fruits, fish, and unrefined foods — was linked in a study to a lower risk of heart attacks and strokes in people who already suffer from heart disease. The study, involving almost 15,500 patients in 39 countries, is titled “Dietary patterns and the risk of major adverse cardiovascular events in a global study of high-risk patients with stable coronary heart disease,” and published in the European Heart Journal.
Results also revealed that eating larger amounts of healthy foods was more important to this patient group than avoiding unhealthy foods, like the refined grains, desserts, sweets, sugared drinks, and deep-fried foods associated with a Western diet.
“After adjusting for other factors that might affect the results, we found that every one unit increase in the Mediterranean Diet Score was associated with a seven percent reduction in the risk of heart attacks, strokes or death from cardiovascular or other causes in patients with existing heart disease. In contrast, greater consumption of foods thought be less healthy … was not associated with an increase in these adverse events, which we had not expected,” Professor Ralph Stewart, the study’s leader author from Auckland City Hospital, University of Auckland in New Zealand, said in a press release.
“The research suggests we should place more emphasis on encouraging people with heart disease to eat more healthy foods, and perhaps focus less on avoiding unhealthy foods,” he added.
Researchers found that for every 100 participants who ate the highest proportion of Mediterranean foods, there were three fewer heart attacks, strokes, or deaths when compared to 100 participants who ate the least amount of healthy foods during nearly four years of follow-up since the study’s start.
For the research, the team surveyed 15,482 people with stable coronary artery disease (average age was 67). Participants were part of the STABILITY clinical trial — a trial designed to assess if a drug, darapladib, reduced heart attack, stroke and death risks — and filled out a lifestyle survey upon joining.
Simple questions on diet were part of the survey, with participants asked how many times a week they consumed servings of different kinds of meat, fish, dairy foods, whole grains or refined grains, vegetables (minus potatoes) and fruits – typical either of a Mediterranean or Western diet – and about alcohol consumption.
Participants, according to their answers, were attributed a ‘Mediterranean diet score’ (MDS), ranging from a low of 0 to a high of 24 depending on the amount of healthy foods they reported consuming, and a ‘Western diet score’ (WDS) reflecting intake of unhealthy foods.
After a 3.7-year follow-up, a major cardiovascular event (MACE), like a heart attack, stroke or death, was reported by 1,588 subjects (10.1%). Of the 2,885 people with an MDS score of 15 or greater (high healthy food consumption), MACEs occurred in 7.3% of them; of the 4,018 people with mid-range MDS scores (13-14), 10.5% reported MACEs; and of the 8,579 participants with MDS scores lower than 12, a MACE occurred in 10.8%.
“The main message is that some foods — and particularly fruit and vegetables — seem to lower the risk of heart attacks and strokes, and this benefit is not explained by traditional risk factors such as good and bad cholesterol or blood pressure,” Professor Stewart said. “If you eat more of these foods in preference to others, you may lower your risk. The study found no evidence of harm from modest consumption of foods such as refined carbohydrates, deep fried foods, sugars and deserts.” But, he added, “some harm cannot be excluded.”
Serving sizes were not specified in the survey, and left to participants’ interpretation. “This is a limitation because the estimates of foods eaten are relatively crude and imprecise, but also a strength because we were able to show that even though diet is very complex, a few simple questions can identify a dietary pattern associated with a lower risk of recurrent heart attacks or strokes,” Professor Stewart concluded.