Pesco-Mediterranean Diet With Intermittent Fasting

Authors:
O’Keefe JH, Torres-Acosta N, O’Keefe EL, et al.
Citation:
A Pesco-Mediterranean Diet With Intermittent Fasting: JACC Review Topic of the Week. J Am Coll Cardiol 2020;76:1484-1493.

The following are key points to remember from this review about the Pesco-Mediterranean diet with intermittent fasting:

  1. Humans are evolutionarily adapted to obtain calories and nutrients from both plant and animal food sources. Many people overconsume animal products, often-processed meats high in saturated fats and chemical additives. In contrast, while strict veganism has gained popularity for many reasons and has value in certain groups, it can cause nutritional deficiencies (vitamin B12, high-quality proteins, iron, zinc, omega-3 fatty acid, vitamin D, and calcium), and predispose to osteopenia, loss of muscle mass, and anemia. This is not true of a lacto-ovo vegetarian diet, which allows no animal-based food except for eggs and dairy. A 6-year study of 73,308 North American Adventists reported a decreased incidence of all-cause mortality when comparing vegetarians with nonvegetarians. However, when the vegetarians were stratified into vegans, lacto-ovo vegetarians, pesco-vegetarians, and semi-vegetarians, the pesco-vegetarians had lowest risks for all-cause mortality, cardiovascular disease (CVD) mortality, and mortality from other causes.
  2. The authors propose a plant-rich diet rich in nuts with fish and seafood as the principle source of animal food. Known as the Pesco-Mediterranean diet, it is supplemented with extra-virgin olive oil (EVOO), which is the principle fat source, along with moderate amounts of dairy (particularly yogurt and cheese) and eggs, as well as modest amounts of alcohol consumption (ideally red wine with the evening meal), but few red and processed meats.
  3. Both epidemiological studies and randomized clinical trials indicate that the traditional Mediterranean diet is associated with lower risks for all-cause and CVD mortality, coronary heart disease, metabolic syndrome, diabetes, cognitive decline, neurodegenerative diseases (including Alzheimer’s), depression, overall cancer mortality, and breast and colorectal cancers.
  4. The traditional Mediterranean diet has been endorsed in the most recent Dietary Guidelines for Americans and the American College of Cardiology/American Heart Association guidelines. The 2020 U.S. News & World Report ranked it #1 for overall health based upon it being nutritious, safe, relatively easy to follow, protective against CVD and diabetes, and effective for weight loss.
  5. Fish and seafood are important sources of vitamins protein and omega-3 fatty acids, of which the higher blood and adipose tissue are associated with reduced fatal and nonfatal myocardial infarction. When not fried, fish consumption has been associated with reduced risk of heart failure, and the incidence of the metabolic syndrome, coronary heart disease, ischemic stroke, and sudden cardiac death, particularly when seafood replaces less healthy foods.
  6. Unrestricted use of EVOO in the kitchen, on salads (with vinegar), cooking vegetables, and at the table is the foundation of the traditional Mediterranean diet, although olive oil quality is crucial, which makes it expensive. EVOO retains hydrophilic components of olives including highly bioactive polyphenols, which are believed to underlie many of EVOO’s cardiometabolic benefits, such as reduced low-density lipoprotein cholesterol (LDL-C) and increased high-density lipoprotein cholesterol (HDL-C), improved vascular reactivity, enhanced HDL particle functionality, and a lower diabetes risk.
  7. Tree nuts, an integral component of the traditional Mediterranean diet, are nutrient dense rich in unsaturated fats, fiber, protein, polyphenols, phytosterols, and tocopherols. Nut consumption is associated with decreased incidence and mortality rates from both CVD and coronary artery disease (CAD), as well as atrial fibrillation and diabetes. Randomized controlled trials have shown that diets enriched with nuts produce cardiometabolic benefits including improvements in insulin sensitivity, LDL-C, inflammation, and vascular reactivity. A 1-daily serving of mixed nuts resulted in a 28% reduction in CVD risk. Generous intake of nuts does not promote weight gain because of increased satiety and incomplete digestion.
  8. Legumes are an excellent source of vegetable protein, folate, and magnesium and fiber, and like other seeds including peanuts, are rich in polyphenols. 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. Legumes, like fish, are a satiating and healthy substitute for red meat and processed meats.
  9. Dairy products and eggs are important sources of 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 and soft cheeses, are preferred; butter and hard cheese are high in saturated fats and salt.
  10. 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. Eggs are allowed in the Pesco-Mediterranean diet; egg whites are unlimited and preferably no more than 5 yolks/week.
  11. Whole grains, such as barley, whole oats, rye, corn, buckwheat, brown rice, and quinoa, are an integral part of the traditional Mediterranean diet. 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 and there is no evidence that pasta promotes cardiometabolic risk factors. White rice is associated with type 2 diabetes mellitus in Asians but not in Western cohorts, possibly because it is cooked and served plain in Asia and in Western cultures cooked in mixed dishes with vegetables and vegetable oil including EVOO.
  12. The staple beverage of the Pesco-Mediterranean diet is water—which can be flavored but not sweetened. Unsweetened tea and coffee are rich in antioxidants and are associated with improved CVD outcomes. 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 (6-12 oz) consumed with meals.
  13. Time-restricted eating, a type of intermittent fasting, is the practice of limiting the daily intake of calories to a window of time usually between 6-12 hours each day. Intermittent fasting when done on a regular basis has been shown to decrease intra-abdominal adipose tissue and reduce free-radical production. This elicits powerful cellular responses that improve glucose metabolism and reduce systemic inflammation, and may also reduce risks of diabetes, CVD, cancer, and neurodegenerative diseases. After a 12-hour overnight fast, insulin levels are typically low, and glycogen stores have been depleted. In this fasted state, the body starts mobilizing fatty acids from adipose cells to burn as metabolic fuel instead of glucose. This improves insulin sensitivity. Time-restricted eating is not more effective for weight loss than standard calorie-restriction, but appears to enhance CV health even in nonobese people. Fasting may also lower blood pressure and resting heart rate and improve autonomic balance with augmented heart rate variability.
  14. The evidence regarding time-restricted eating is mostly based on animal models and observational human studies. The most popular form of time-restricted eating involves eating two rather than three meals and compressing the calorie-consumption window. No head-to-head studies have been performed to assess the optimal time window.

Clinical Topics: Diabetes and Cardiometabolic Disease, Dyslipidemia, Prevention, Lipid Metabolism, Nonstatins, Diet

Keywords: Adipose Tissue, Blood Glucose, Caloric Restriction, Cheese, Cholesterol, Coronary Disease, Diabetes Mellitus, Dairy Products, Diet, Diet, Mediterranean, Eggs, Fasting, Fatty Acids, Omega-3, Metabolic Syndrome X, Neoplasms, Nuts, Primary Prevention, Vegetables, Vitamins, Weight Loss


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