A Pesco-Mediterranean Diet With Intermittent Fasting

JACC Review Topic of the Week

James H. O'Keefe, MD; Noel Torres-Acosta, MD; Evan L. O'Keefe, MD; Ibrahim M. Saeed, MD; Carl J. Lavie, MD; Sarah E. Smith, PHD; Emilio Ros, MD, PHD


J Am Coll Cardiol. 2020;76(12):1484-1493. 

In This Article

Other Key Components of the Mediterranean Diet: EVOO, Nuts, and Legumes

Unrestricted use of EVOO in the kitchen and at the table is the foundation of the traditional Mediterranean diet, although olive oil quality is crucial.[23] Unlike the common variety of olive oil and most edible seed oils—which are refined, EVOO is unrefined. It is obtained by cold pressing olives, and in this sense is equivalent to a pure olive juice. EVOO retains hydrophilic components of olives, among them highly bioactive polyphenols, which are believed to underlie many of EVOO's cardiometabolic benefits, such as reduced LDL-C and increased high-density lipoprotein cholesterol, improved vascular reactivity, enhanced high-density lipoprotein cholesterol functionality, and a lower diabetes risk.[23,32] Importantly, the EVOO arm of the PREDIMED trial provided first-level scientific evidence of its cardioprotective effects within the context of the Mediterranean diet.[23]

Given the bitter taste of polyphenols, their presence in olive oil is readily perceived as a tingling or burning in the back of the throat that appears a few seconds after swallowing a sample of the EVOO.[32] Since vegetables are at the basis of the Pesco-Mediterranean diet, generous use of EVOO (along with vinegar) for dressing salads and vegetable dishes encourages the consumption of higher amounts of these plant foods. EVOO is also recommended for simmering minced tomatoes, garlic, onions, and aromatic herbs as a "sofrito" sauce to use on vegetables, pasta, rice, fish or legumes, as recommended in the PREDIMED Mediterranean diets (Table 2).[23]

Tree nuts are an integral component of the traditional Mediterranean diet.[33] Nuts are nutrient-dense foods rich in unsaturated fats, fiber, protein, polyphenols, phytosterols, tocopherols, and nonsodium minerals. This unique nutritional profile makes nuts one of the most effective foods for improving long-term health outcomes.[34] RCTs have shown that diets enriched with nuts produce cardiometabolic benefits including improvements in insulin sensitivity, LDL-C, inflammation, and vascular reactivity.[33,34] Observational studies have suggested that nut consumption is associated with decreased incidence and mortality rates from both CVD and CAD, as well as decreased risks of atrial fibrillation and diabetes.[35] In 1 arm of the PREDIMED trial, 1 daily serving of mixed nuts resulted in a 28% reduction in CVD risk, again providing first-level scientific evidence for the cardioprotective effect of nuts within the context of the Mediterranean diet.[23] Generous intake of nuts does not promote weight gain because of increased satiety and reduced metabolizable energy (part of nuts' fat is lost in the feces because of incomplete digestion).[33,36]

Legumes also play a central role in the traditional Mediterranean diet, and they are an excellent source of vegetable protein, folate, and magnesium and fiber, and like other seeds, are rich in polyphenols.[37] Consumption of legumes has been linked to a reduced risk of incident and fatal CVD and CAD, as well as improvements in blood glucose, cholesterol, blood pressure, and body weight.[37] Legumes, like fish, are a satiating and healthy substitute for red meat and processed meats.

Two important sources of protein in the usual diet, dairy products and eggs, need to be mentioned. Dairy products contribute important nutrients to the diet, including protein, nonsodium minerals, probiotics, and vitamin D. Although there is no clear consensus among nutrition experts on the role of dairy products in CVD risk, they are allowed in this Pesco-Mediterranean diet. Fermented low-fat versions, such as yogurt, kefir, and soft cheeses, are preferred; butter and hard cheese are discouraged, because they are high in saturated fats and salt.[38]

Eggs are composed of beneficial nutrients including all essential amino acids, in addition to minerals (selenium, phosphorus, iodine, zinc), vitamins (A, D, B2, B12, niacin), and carotenoids (lutein, zeaxanthin). Although each yolk contains about 184 mg of dietary cholesterol, large prospective cohorts suggest that egg consumption is unrelated to serum cholesterol, and does not increase CVD risk.[39,40] Eggs are allowed in the Pesco-Mediterranean diet, preferably no more than 5 yolks/week (egg whites can be consumed without limit). Eggs are another satiating and healthy substitute for red meat and processed meats.

Whole grains, such as barley, whole oats, rye, corn, buckwheat, brown rice, and quinoa, are an integral part of the traditional Mediterranean diet. Anecdotally, Americans often consider pasta, pizza, and white bread to be central components of the Mediterranean diet. Commercial, precooked pasta or pizza should be consumed only in small amounts in the Pesco-Mediterranean diet, but homemade pizza and mixed pasta dishes, or mixed rice dishes like paella, a staple in many regions of Spain, are legitimate and healthy Mediterranean foods.[41] Pasta is an example of a starchy food that has a low glycemic index despite being a refined carbohydrate. In the context of a low glycemic index dietary pattern such as the Mediterranean diet, pasta does not adversely affect adiposity and may even help reduce body weight according to a recent meta-analysis of RCTs.[42] The results of 2 recent large Italian cross-sectional studies concur with the RCTs' findings.[43,44] Likewise, there is no evidence that consumption of pasta promotes cardiometabolic risk factors.[41,44,45]

Concerning white (refined) rice, its consumption was not associated with CVD or CAD in an analysis of 3 large U.S. cohorts.[46] According to the meta-analysis by Hu et al.,[47] white rice consumption was associated with an increased risk of type-2 diabetes in 3 Asian cohorts but not in 4 Western cohorts. This geographically contrasting diabetes risk is likely due to the way rice is prepared in Asia (plain cooked) and in Western cultures (cooked in mixed dishes with vegetables and vegetable oil). In Mediterranean cultures, white rice, like pasta, is usually prepared with a sofrito sauce including EVOO, tomatoes, other vegetables, and aromatic herbs, thereby adding beneficial nutrients and bioactives to these starchy but nutritive foods that are likely to further lower their glycemic index. So, if homecooked and prepared the Mediterranean way, mixed pasta and white rice dishes are both tasty and healthy ingredients to the Pesco-Mediterranean diet.

The staple beverage of this diet is water—either still or carbonated, which can be flavored but not sweetened. Unsweetened tea and coffee are noncaloric beverages rich in antioxidants, particularly polyphenols, and are associated with improved CVD outcomes.[48,49] If alcohol is consumed at all, dry red wine is recommended, with the ideal amount being a single glass (≤6 oz) for women and 1 or 2 glasses/day for men (6 to 12 oz) consumed with meals.[50]