People who regularly eat a ‘Mediterranean diet’ are not at a risk of developing heart diseases, even if they consume ‘junk food’ at times. A new study published on 25th March in the BMJ claims long-term consumption of Mediterranean foods can nullify the harmful effects caused by eating a Western-style diet.

Junk or fast food consumption is known to disrupt the normal metabolic reactions in the human body, which as a result damages the heart and ultimately leads to the development of cardiovascular diseases. However, the study suggests a Mediterranean diet can neutralize such effects, so people can indulge in junk food, without any health risks.

The US Centers for Disease Control (CDC) has estimated 610,000 people die due to heart diseases which is 1 in 4 deaths in the United States every year. In contrast, epidemiological data has shown the incidence of heart diseases being lower in the Mediterranean countries when compared to the United States, which indicates the dietary pattern of the Mediterranean regions prevent coronary heart diseases.

A ‘Mediterranean diet’ is a collection of different foods from 16 countries bordering the Mediterranean Sea, so it cannot be restricted into a single category. Basically such a diet entails eating less saturated fats and eating more of monounsaturated fats, which does not raise the blood cholesterol and blood pressure, and can be characterized as the regular and increased consumption of some dietary items and the exclusion of others. For example, a person on a Mediterranean diet eats more fruits, vegetables, olive oil, bread, cereals beans, nuts, seeds, etc, and lowers the consumption of dairy products, fish, poultry (eggs), red meat, wine etc. A Western-style diet, on the other hand, is majorly made up of junk, processed or fast foods and has long been regarded as a contributing factor of poor general health and a short lifespan.

Dr Ralph Stewart, a professor at the University of Auckland in New Zealand, was the lead author of the study. “The study found no evidence of harm from modest consumption of foods such as refined carbohydrates, deep fried foods, sugars and deserts,” said Dr Stewart. “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.”

The large follow-up cohort study was carried out on 15, 482 people, with a mean age of 67 years from 39 different countries around the world. All of the study subjects had stable coronary heart diseases. The participants were asked to fill a lifestyle questionnaire with questions on their dietary habits e.g., amounts, types and frequency of different foods they consumed. The subjects were also followed up to find out the occurrence of adverse cardiovascular events e.g., non-fatal myocardial infarction, non-fatal stroke, or fatal cardiovascular events.

A Mediterranean diet score (MDS) which ranged from 0 to 24 was given to each participant. The higher the consumption of Mediterranean foods was recorded, the higher the score was awarded. The participants, whose diets included refined grains, sweets, desserts, sugary drinks, and deep fried foods, were also given a Western diet score (WDS). Individuals who consumed three or more fruits every day earned four MDS points and those eating fruit less than once per week did not get any points.

The results obtained after a 3.7-year follow-up showed people with a higher MDS had a lower risk of suffering from cardiovascular events. Since only 7.3% of the individuals with a 15% or higher MDS had experienced an adverse heart event. Likewise, 10.5% of the individuals had an adverse heart incident with a 13-14 MDS, while 10.8% of the individual suffered from a heart event with an MDS lower than 12. So as the MDS decreased in the subjects the occurrence of a major adverse cardiac attack increased. The data also showed 10% of the subjects drank a sugary carbonated drink every day. No significant difference adverse or fatal heart events were observed for people who had a balanced WDS and MDS.

“In a large geographically diverse cohort of high risk patients with stable coronary heart disease, a diet containing more food groups included in the traditional Mediterranean diet… was associated with a lower risk of major cardiovascular adverse events and all cause deaths,” said the researchers, led by Dr Ralph Stewart. “In contrast, greater consumption of foods thought to be less healthy and more typical of Western diets, was not associated with an increase in these adverse events, which we had not expected.”

Other than the high consumption of fresh produce, what makes the Mediterranean diet so beneficial for health? For instance, take ‘olive oil’ which is a staple of the Mediterranean cuisine, it has been found to contain compounds which are incredibly beneficial for the human body. The phenolic compounds called ‘oleuropein’ and ‘hydroxytyrosol’, found in extra virgin olive oil, have been shown to have an incredibly high antioxidant activity in preclinical studies against cardiovascular and metabolic diseases. When levels of oxygen or peroxide radical species increase in the body, they damage the cardiovascular cavity. The lipophilic and hydrophilic phenols present in olive oil act as free radical scavengers and radical chain breakers in the human body when consumed through diet.