A Pesco-Mediterranean diet rich in plants, nuts, whole grains, extra-virgin olive oil, and fish and/or seafood is ideal for optimizing cardiovascular health, according to a cumulative review published today in the Journal of the American College of Cardiology. Intermittent fasting is recommended as part of this diet.

The traditional Mediterranean diet has been endorsed by national guidelines as well as the 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease. The Mediterranean diet consists of plant foods (fruits, vegetables, legumes, whole grains, seeds, tree nuts and olives), fish/seafood, olive oil, and moderate amounts of dairy products (yogurt and cheese) and eggs. Multiple studies and randomized clinical trials have indicated that the diet is associated with lower risk for heart disease, diabetes, cognitive decline, depression and some cancers.

"Although humans are omnivores and can subsist on a myriad of foods, the ideal diet for health remains a dilemma for many people," said James H. O'Keefe, MD, director of preventive cardiology at Saint Luke's Mid America Heart Institute, and lead author of the study. "Plant-rich diets reduce cardiovascular disease risk; however, veganism are difficult to follow and can result in important nutrient deficiencies. On the other hand, many people in modern Western cultures over-consume meat, particularly highly processed meat from animals raised in inhuman conditions. We propose the Pesco-Mediterranean diet as a solution to this 'omnivore's dilemma' about what to eat."

Previous studies have supported including fish as a part of a heart-healthy diet. The 2015-2020 Dietary Guidelines for Americans recommend adults consume fish at least twice a week in place of red meat, poultry or eggs. A pescatarian diet includes fish and/or seafood as the primary source of protein and minimizes the consumption of red meat or poultry. A meta-analysis of five prospective dietary studies found that compared to regular meat-eaters, coronary artery disease mortality was 34% lower in those following a pescatarian diet.

A Pesco-Mediterranean diet also emphasizes using extra-virgin olive oil in place of butter or other fats. Extra-virgin olive oil is a higher-quality, unrefined olive oil, and has been shown in previous studies to have cardiometabolic benefits, such as reducing low density lipoprotein ("bad") cholesterol and increasing high density lipoprotein ("good") cholesterol. The researchers recommend using generous amounts of extra-virgin olive oil (high in polyphenol antioxidants) along with vegetable dishes. To provide an additional source of healthy fats and fibers, the Pesco-Mediterranean diet includes tree nuts. The PREDIMED trial, a randomized clinical trial of primary heart disease prevention, showed a daily serving of mixed nuts resulted in a 28% lower risk of heart disease.

"There is no clear consensus among nutrition experts on the role of dairy products and eggs in heart disease risk, however we allowed for them in the Peso-Mediterranean diet," O'Keefe said. "Low-fat yogurt and cheeses are preferred; butter and hard cheese are discouraged due to a high concentration of saturated fats and salt. Eggs contain beneficial nutrients and can be a healthy substitute for red meat; however, we recommend no more than five yolks be consumed per week."

Intermittent fasting, the practice of limiting daily intake of calories in a specific time window (usually between eight to 12 hours) each day, has been shown to reduce inflammation and improve insulin sensitivity by forcing the body to switch from burning glucose to fatty acids (usually from belly fat) as the primary metabolic fuel. The most common form of intermittent fasting is timed-restricted eating, consisting of limiting to two, rather than three, meals per day and shortening the calorie-consumption window. Evidence regarding time-restricted eating is preliminary and requires more research.

"Our ancient ancestors did not have access to an unlimited supply of food throughout the year. Nor did they routinely eat three large meals, plus snacks, daily. Focusing on fresh whole foods, along with fish, bestows a range of health benefits, particularly when it comes to cardiovascular health. The Pesco-Mediterranean diet with daily time-restricted eating is an ideal cardioprotective diet," O'Keefe said.