Emphasising healthy foods in your diet, not just banishing "bad" foods, may be the key to avoiding heart attack and stroke, a new study suggests.
A bit of unhealthy food
Researchers analysed the eating habits of thousands of older adults worldwide with heart disease and found results that might surprise you.
"Eating a healthy diet seems to have protective effects, but unhealthy foods don't seem to cause any harm," said lead researcher Dr Ralph Stewart, a cardiologist at Auckland City Hospital in New Zealand.
Nutritionists didn't agree with the latter notion, however, stressing that more research is definitely needed.
Read: Why doctors should be recommending a Mediterranean diet for heart health
The new study found that for every 100 people eating the healthful, Mediterranean-style diet, three fewer heart attacks, strokes or deaths occurred, compared with the same number of adults eating the so-called western diet, the study found.
A Mediterranean diet is rich in fruits, vegetables, fish and unrefined foods. A western diet includes sugary desserts, meat and fried foods – all the so-called "bad" foods, said Stewart.
"Traditionally, dietary advice has focused on avoiding unhealthy foods, but in terms of reducing risk, it's probably increasing more healthy foods rather than avoiding unhealthy foods," he said.
Other things more important than diet
"It's a lack of healthy foods in many people's diets that's the problem, not so much eating unhealthy foods."
However, unhealthy foods do increase the risk for obesity, especially in youth, and obesity is a major cause of health problems, Stewart said.
Read: Mediterranean diet benefits heart
"Once you've got heart disease, other things might be more important than diet," Stewart said.
The report was published in the European Heart Journal.
For the study, Stewart and his colleagues asked more than 15,000 people from 39 countries to complete a lifestyle questionnaire when they enrolled in a trial assessing treatment with the anti-cholesterol drug darapladib.
All had stable heart disease, and their average age was 67. GlaxoSmithKline, the drug's maker, helped to fund the study.
Participants were asked how many times a week they ate foods such as meat, fish, dairy, whole grains or refined grains, vegetables, fruit, desserts, sweets, sugary drinks, deep-fried foods and alcohol.
Nutrition expert objects
After nearly four years of follow-up, about 7 percent of those with the highest scores of adhering to a Mediterranean diet (eating the largest amount of healthy foods) suffered a heart attack or stroke or died, compared with almost 11 percent of those who scored the lowest on following that healthy diet, the researchers found.
Read: Sugar and carbs cause heart disease, not cholesterol
However, Stewart said no evidence of harm was seen from modest amounts of unhealthy foods, such as refined carbohydrates, deep-fried foods, sugars and desserts.
But one nutrition expert objected to that conclusion.
"To say that dietary advice should focus on only eating healthy foods and not on significantly limiting the unhealthy foods in the typical Western diet is absurd," said Samantha Heller, a senior clinical nutritionist at New York University Medical Centre, in New York City.
In general, foods commonly found in the Mediterranean diet can include hummus, yogurt, cucumbers, garlic, olive oil, pasta, nuts, beans, fish, fresh fruit, salads, and fresh and grilled vegetables like zucchini, tomatoes and eggplant, she said.
Research has linked the Mediterranean diet with many health benefits, said Heller, noting it's a lifestyle, not a specific diet.
Read: At risk of heart disease? You can safely eat six eggs a week
In contrast, the western diet is characterised by big portions, high intake of red and processed meats, refined carbohydrates like sugary cereals and cookies, highly processed foods, deep-fried foods like French fries, junk foods and sugary beverages, she said.
Results aren't ironclad
Many studies have shown that the western dietary pattern is associated with an increased risk of heart disease, obesity, autoimmune diseases, cancer, diabetes, mental decline and gastrointestinal diseases such as Crohn's disease, Heller said.
Another expert noted that the new study results aren't ironclad. "These findings are based on dietary questionnaires, so clinical trials will be required to confirm these conclusions," said Dr Gregg Fonarow, a professor of cardiology at the University of California, Los Angeles.
"However, clinical trials testing different diets to prevent or treat heart disease have, so far, yielded disappointing results," he said.
Stewart also warned that his study doesn't mean people could eat unhealthy foods with abandon. Noting that the researchers were unable to pinpoint serving sizes or quantities of food eaten, he said the findings may be skewed by the lack of detailed diet data.