Mediterranean Diet Powers 'Good' Cholesterol's Abilities
The Mediterranean diet enriched with olive oil improves HDL function in adults at high risk for heart disease.
A Mediterranean diet rich in olive oil helps boost the functioning of good cholesterol, based on a recent study of patients at high risk for heart disease in Barcelona, Spain.
Published in the American Heart Association journal Circulation, this study looked at the impact of diet on the function of high-density lipoproteins (HDL). High-density lipoproteins, often referred to as “good” cholesterol, help remove bad forms of cholesterol from the bloodstream. A Mediterranean diet, which is rich in fruits, vegetables, whole grains and healthy fats, has been shown to improve cholesterol levels and heart health. But while high HDL levels are associated with lower risk of heart disease, exactly how HDL lowers heart risks is less clear.
To learn more, researchers analyzed data from the PREDIMED trial, which included 296 Spanish adults at high risk for heart disease. Participants were assigned to the Mediterranean diet enriched with olive oil or nuts, or a standard low-fat diet for one year.
Based on changes in blood tests from the start and end of the study, none of the diets had a significant impact on HDL levels among participants after one year. However, researchers did find improved HDL function among participants in the Mediterranean diet compared to the low-fat diet. For example, the Mediterranean diet improved the ability of HDL particles to remove cholesterol from the blood, a process called efflux capacity. The Mediterranean diet with olive oil also improved HDL’s ability to fight inflammation and widen the blood vessels.
However, authors note that the only significant differences in HDL function were between participants on the Mediterranean diet enriched with olive oil compared to those on the standard low-fat diet.
What findings suggest is that boosting HDL function, rather than HDL levels, may be the key to reducing cardiovascular risk. While there’s no question that a high HDL is associated with lower heart risks, studies suggest that raising HDL does not necessarily improve outcomes. This study may help explain why, as HDL function may be more important when it comes to heart health.
Questions for You to Consider
- What is the Mediterranean diet?
The Mediterranean diet is a way of eating rather than a formal diet plan. It features foods eaten in Greece, Spain, southern Italy and France, and other countries that border the Mediterranean Sea.
The Mediterranean diet emphasizes eating foods like fish, fruits, vegetables, beans, high-fiber breads and whole grains, and olive oil. Meat, cheese, and sweets are very limited. The recommended foods are rich with monounsaturated fats, fiber, and omega-3 fatty acids.
The Mediterranean diet is like other heart-healthy diets in that it recommends eating plenty of fruits, vegetables, and high-fiber grains. But in the Mediterranean diet, an average of 35-to-40% of calories can come from fat. Most other heart-healthy guidelines recommend getting less than 35% of your calories from fat. The fats allowed in the Mediterranean diet are mainly from unsaturated oils, such as fish oils, olive oil, and certain nut or seed oils (such as canola, soybean, or flaxseed oil). These types of oils may have a protective effect on the heart. For more information, read this overview of the Mediterranean diet.
- What are the risks associated with high cholesterol?
- High cholesterol can cause atherosclerosis, the build-up of plaque on artery walls. This accumulation of deposits can cause serious complications, such as chest pain, heart attack and stroke. High cholesterol is largely preventable and treatable, so getting screened and making healthy lifestyle choices can go a long way in controlling cholesterol levels.