They noted the types of fruits, vegetables and meats the participants consumed, placing them into categories such as organic or not or whole-grain or not. They also recorded the way the meals were prepared, marking them fried, baked, boiled and so on.
At the end of the nearly five-year period, there were 5,256 heart disease events.
After analyzing the all of the data, scientists found that the Mediterranean diet was most beneficial to those with higher incomes or levels of education.
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Why the disparity?
Researchers believe quality of foods may play a role.
"We also found that higher-SES [socioeconomic] 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, as compared with conventionally grown foods,” the study said. “We might then speculate that the quality of the bundle of foods that make up the MD [Mediterranean diet] actually differs across SES.”
They also think the way foods are prepared can change the diet’s effectiveness.
“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,” the study read.
To close the gap, researchers say more strategies should be in place to reduce socioeconomic imbalances in health. That includes “facilitating access to foods with higher nutritional values likely associated with improved health outcomes.”
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