What is the Mediterranean diet?
The term "Mediterranean diet" is used today to describe the traditional eating habits of the countries along the Mediterranean, mainly Greece and southern Italy. Nevertheless, it should be understood as not just a strict reference to the preferences shown by these people in their daily food choices, because the original meaning of the word diaita in Greek does not only refer to food or dietary choices, but a certain kind of "The way of life" is more in line with the modern concept of "lifestyle" .
It is relatively difficult to determine the origin of this diet, but it is likely that it has developed with the population living in the Mediterranean basin since the advent of civilization. Throughout history, the Mediterranean diet has incorporated some of the habits brought by the conquerors, while maintaining the vitality and function of most of the previous local traditions. The roots of the Mediterranean diet can be found in ancient societies belonging to the Fertile Crescent-the geographic region of the Near East between the eastern end of the Mediterranean Sea and the Persian Gulf, including Mesopotamia, Canaan, and according to some, northern Egypt .
Since the oldest times, food has spread between countries and cultures in the Mediterranean basin. Hieroglyphic records mention the export of wine and olives from Canaan to Ancient Egypt. The city-state of Athens uses the olive tree as its symbol, and the ancient Greeks left the olive branch to mankind as a symbol of peace. After Alexander the Great conquered this territory in the 4th century BC, the influence of Greek food was brought to the Near East . As a plant-based diet, the Mediterranean diet has been continuously influenced because continuous plant species are imported from other geographic regions of the world and adapted in the Mediterranean basin.
Where is the Mediterranean?
Mediterranean diet in English is the mediterranean diet . The mediterranean sea, the intercontinental sea that separates Europe and Africa from the Atlantic Ocean in the west and Asia in the east. It is often referred to as the incubator of Western civilization. This ancient "sea between land" is located in a deep, slender and almost inland irregular depression between 30° and 46° north latitude, 5°50' west longitude and 36° east longitude. The countries surrounding the Mediterranean in clockwise order are Spain, France, Monaco, Italy, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Albania, Greece, Turkey, Syria, Lebanon, Israel, Egypt, Libya, Tunisia, Algeria, Morocco; Malta And Cyprus is an island country on the sea.
Mediterranean food culture
The traditional eating habits seen in the geographic regions around the Mediterranean Sea, although they vary with certain food choices and cooking practices of each country and culture, share a common set of basic characteristics. The specific dietary dimensions of the Mediterranean lifestyle include plant-based foods that use vegetables, fruits, grains, nuts, and legumes, most of which are cooked with a large amount of olive oil, and moderate use of fish, seafood or dairy products, as well as meat and alcohol The intake is limited (mostly red wine). This unique diet pattern is the result of a complex and thousand-year interaction between the natural food resources available in the Mediterranean environment and the human elements that have historically lived in the Mediterranean basin. It has gained new value in the last century and has become a precious food. Medical tools in the contemporary world.
At the moment when people are generally aware of the health benefits associated with the Mediterranean diet, its paradoxical fate is that it may disappear on its native territory. Globalization, the introduction of Western habits, changes in lifestyles, and the unique environment of modern civilization have brought heavy costs to traditional Mediterranean diets. At the same time, when international guidelines included it as a recommended healthy eating pattern, the United Nations Educational, Scientific and Cultural Organization (UNESCO) regarded the Mediterranean diet as an "emergency protection of intangible cultural heritage." Given this contradictory position between universal medical recognition and cultural extinction.
The food patterns along the Mediterranean Sea are largely influenced by the three main monotheistic beliefs that have succeeded in the region: Judaism, Christianity, and Islam. These religions also adopt, sustain life, and regard some basic components of the Mediterranean way of life as sacred .
Principles of the Mediterranean diet
The Mediterranean diet is not the unique diet that the term "diet" refers to today. Each region in the Mediterranean Basin has its own recipes, preferences and restrictions. The term "Mediterranean diet" is best understood as a special "eating pattern" with a specific set of interrelated characteristics. Descriptions that only include some foods that exist in popular culture while ignoring the lack of other traditional foods or allowing the addition of foods belonging to other food cultures and patterns should not be accepted as a suitable version of the Mediterranean diet. The true Mediterranean diet should be regarded as the "whole", including all its characteristics, not just a part of it. First, olive oil plays a central role in the cooking process and is therefore the main source of dietary fat. Cheese is used in limited supply, usually in salads. The percentage of meat, milk, and eggs is low and the quantity is small, and processed meat and sweets are almost non-existent. Therefore, the Mediterranean diet actually represents the only traditional diet in which saturated fats and trans fats are essentially small. Secondly, the consumption of olive oil is related to a higher intake of vegetables, such as salad cooking and the same high intake of legumes in food prepared by heating, which means that the Mediterranean diet is essentially a plant-based diet. . The other main components of the Mediterranean diet are whole grains, nuts, fresh fruits and moderate fish intake. However, there are indeed some differences in food intake between different countries. For example, the total fat consumption in Greece is very different. Greece has reached 40% or more of the total daily calorie intake, while the fat intake in Italy is restricted to less than 30% of the daily calorie intake. The constant feature between the different regions of the Mediterranean basin is the high ratio of monounsaturated fat to saturated fat, far exceeding the similar ratio in Northern Europe or North America. Different countries also have differences in the choice of other food sources. Features Italian pasta diet is a food with a higher amount, and the characteristics of the Mediterranean diet is the Spanish variant of fish and seafood food useThe amount is high. A literature review that takes into account the differences between Mediterranean diet countries found that from one case to another, it contains three to nine servings of vegetables, half to two servings of fruit, one to thirteen servings of grains, and as many as eight servings of olive oil. . However, the changes in nutritional composition seem to be smaller than the changes in the number of servings of different foods, because in most cases, the choices of different food groups complement each other to provide the above-mentioned overall single characteristic.
Due to this geographic difference in food choices, current guidelines consider different combinations of food groups to form a Mediterranean diet. There are three main variants of the diet pyramid to describe the Mediterranean diet: Oldway's Preservation and Exchange Trust pyramid, the traditional Mediterranean diet of the Greek nutrition guidelines, and the Mediterranean Diet Fund The pyramid (the Mediterranean Diet Foundation pyramid.). Some of these models retain the characteristics of traditional eating habits, while others have been modified in time to better adapt to the availability, nutritional needs and eating habits of today’s food supply.
Geographical origin of plant species of the Mediterranean diet
|Native plants of the Mediterranean||Olives, borage, beets, capers, lupins, asparagus, watercress, mallow, thistle, grapes, beets, tiger fruit, parsley, cumin, coriander, fennel, oregano, rosemary, sage Grass, lemon balm, coriander, fenugreek, bay leaf, saffron, mushroom|
|Plants from other parts of Asia||Rice, buckwheat, wheat, barley, chickpeas, soybeans, lentils, beans, onions, garlic, leeks, cabbage, broccoli, cauliflower, radish, spinach, cucumber, yam, arugula, banana, coconut, fig, apple, papaya , Pear, mango, plum, cherry, raspberry, lemon, cucumber, kiwi, almond, hazelnut, walnut, chestnut, marjoram, tarragon, pepper, saffron, turmeric, clove, ginger|
|Plants native to Africa||Millet, sorghum, artichoke, okra, watermelon, melon|
|Plants native to America||Corn, other beans, peanuts, tomatoes, peppers, eggplant, pumpkin, zucchini, potatoes, sweet potatoes, prickly pears, cashews, sunflower seeds, avocados, coffee, chocolate, chili, allspice, pink pepper|
Discovery and recognition of the health benefits of the Mediterranean diet
The person responsible for noting the health protection of the Mediterranean lifestyle and coining the term "Mediterranean diet" is Ancel Keys. As an expert in biology and animal physiology, Case focused on the effects of hunger on the human body at the end of World War II, looking for nutritional techniques that can restore health after hunger. While paying attention to the issue of hunger, data on morbidity and mortality in post-war Europe appeared in his eyes. He was surprised to note that in countries where the famine caused people to restrict the typical high-fat, high-calorie diet, acute coronary attacks dropped sharply, and when these countries recovered after the war and the population feeding changed again, the situation was reversed. the trend of. At the same time, Case was also aware of the high incidence of heart disease among wealthy middle-aged businessmen in the United States, so he began to suspect that diet might affect overall health, especially the risk of cardiovascular disease. In the era when the concept of risk factors has not yet been born .
In 1951, during a one-year leave of work in Oxford, he heard that the incidence of heart disease in southern Italy was very low. Case went to Naples and opened a portable laboratory there. He quickly confirmed the stories he heard about the low incidence of coronary ischemic disease, and he also noticed that most local people showed low cholesterol levels. Case conducted similar assessments in other European and African countries, and gradually discovered that a diet rich in saturated fat was associated with elevated serum cholesterol levels and a high risk of coronary heart disease.
In 1955, when Ancel Keys first proposed the idea that his diet causes heart disease at an international conference of the World Health Organization, he was met with suspicion, even the world-renowned cardiologist George Picker. Sir George Pickering also asked him to provide more evidence. It is temporarily impossible to do so, he used this as a motivation to design and implement a research project, which will become the so-called Seven Nations Research. He chose to examine tobacco use, diet, physical activity, weight status, blood pressure, heart rate, vital capacity, blood cholesterol levels, and electrocardiogram readings in seven cohorts of all 40 to 59-year-old men living in some carefully selected rural communities in the United States. Evaluate. The former Yugoslavia, Italy, Greece, Finland, the Netherlands, the United States and Japan. Yugoslavia was chosen because it offers the possibility of studying people with two different dietary patterns in the coastal and inland regions of the country. Italy is the country where Ancel Keys made preliminary observations of the low incidence of heart disease in the context of a typical (though not yet designated) Mediterranean lifestyle. Greece offers an opportunity to evaluate people who have a high-fat diet but very low intake of saturated fat, because the main source of fat is olive oil, which is rich in monounsaturated fatty acids. The population of Finland is very healthy, but the incidence of heart disease is high and the intake of saturated fat is very high. The Netherlands is a representative of a mild diet, mixing meat, butter and vegetables. A sample of the US population was selected as a representative of the high incidence of cardiovascular disease and geographic stability. Japan offers the possibility of studying people with the least dietary fat intake. A total of 12,763 subjects were screened. After 5 and 10 years, respectively, the research team returned to all the populations initially screened and collected data on participants who experienced a coronary attack at the same time.
When medical data was submitted for statistical analysis, the results showed significant differences between geographic regions. In this order, Crete, Japan and Corfu have the lowest rates of heart disease. On the other hand, Finland has the highest ratio, and the United States ranks second. A direct comparison between Crete and Finland shows that the incidence of coronary heart disease in the latter is almost 100 times higher (0.1% vs. 9.5%). 77% of Finns have a total cholesterol level higher than 200 mg/dL, compared to only 3% of Japanese. Dietary calories from total fat account for 9% to 40% of total daily intake, but these numbers are not always related to the incidence of heart disease, because Greece is one of the countries with the highest total fat intake. Calories from saturated fat vary from 3% to 22%; the correspondence between heart attack rate and saturated fat is convincing. Therefore, in Finnish and American communities, the high intake of saturated fat is related to the high incidence of cardiovascular disease.
Ancel Keys then realized that the dietary habits inherited in the traditional Mediterranean population (especially Greece and southern Italy) are associated with a reduced risk of cardiovascular disease. He created these eating habits under the term "Mediterranean diet" and co-authored two books on the subject: Eat well and stay healthy and How to eat well and stay healthy in the Mediterranean way. He adopted his own Mediterranean dietary advice and died in 2004 at the age of 100. His efforts and research have also been recognized and respected all over the world.
Further confirm the health benefits of the Mediterranean diet
The Seven-Country Study has an observational design and limited ability to prove cause and effect. Keys and his team focused on the relationship between total serum cholesterol levels and the dietary factors that affect them, rather than the possibility that the entire Mediterranean diet would be beneficial to cardiovascular health. Although studies in seven countries pointed out a link between eating habits and cardiovascular risk, the concept of "Mediterranean diet" remained in the background until the early 1990s.
The Lyon Diet Heart Study is a secondary prevention randomized controlled trial designed to evaluate the impact of a modern, French adapted version of the Mediterranean diet on patients who have already suffered from acute myocardial infarction. In order to best mimic the characteristics of the Greek diet, which is naturally rich in omega-3 alpha-linolenic acid but lacks omega-6 linoleic acid, the author decided to combine rapeseed oil with olive oil. Surprisingly, the results of this study not only showed a 50% reduction in new acute coronary attacks, but also reduced new cancer cases and all-cause mortality. The health benefits of the Mediterranean diet cannot be ignored, and the concept of "Mediterranean diet" has entered medical consciousness.
In the following years, the confirmation of the cardiovascular benefits of the Mediterranean diet became more powerful. In the large cohort of the European Prospective Survey on Cancer and Nutrition (EPIC)-Elderly Prospective Cohort Study, 74,607 healthy participants from nine European countries were recruited who were 60 years or older and used the Mediterranean diet score The variants estimate compliance with the Mediterranean diet. The score is obtained by adding up the nine partial scores of 0 or 1, which represents the intake of nine specific dietary ingredients, so it varies between a total of 0 (lowest compliance) and 9 (highest compliance) . After 4 years of follow-up, it was found that a 2 point increase in the Mediterranean diet score was associated with a significant 33% reduction in cardiovascular death. The other two Spanish cohort studies, as well as the Transnational Healthy Aging: Longitudinal Study in Europe (HALE) project, confirmed a higher adherence to the Mediterranean diet and a reduction in the number of cardiovascular events, also in a primary prevention setting. A reduction in the incidence of cardiovascular events has also been found in several secondary prevention studies.
The most recent large trial that provided strong evidence for the Mediterranean diet was the Spanish Preventive Mediterranean Diet (PREDIMED) study. As a primary prevention randomized controlled trial, it recruited 7447 subjects without clinical symptoms of cardiovascular disease. One of them was a control group recommended to follow a low-fat diet, and the other was a Mediterranean diet supplemented with extra virgin olives. The active experimental group is oil or mixed nuts. Although all three groups showed relatively few acute cardiovascular events, because all three groups’ diets were healthy cardioprotective diets, the group randomly assigned to the Mediterranean diet still showed a 30% reduction in the risk of cardiovascular complications, so People are impressed with a 40% reduction in stroke risk. In PREDIMED, a specialized and validated 14-item screening tool (Mediterranean Diet Compliance Screener, or MeDiet Score) was used to measure compliance with the Mediterranean diet, and it was found to be negatively correlated with the incidence of cardiovascular events. Other analyses of the PREDIMED study population further indicate that the Mediterranean diet appears to reduce the expression of pro-atherosclerosis genes, surrogate markers of cardiovascular risk, such as waist-to-hip ratio, lipid fraction, lipoprotein particles, oxidative stress, and inflammatory markers , But there is also the risk of metabolic syndrome and type 2 diabetes. However, due to the low incidence of cardiovascular events in all three intervention groups, the preliminary results of the PREDIMED study have been challenged, which may cause the above-mentioned statistically significant differences on the basis of imperfect randomization procedures. This allows some of the characteristics of the baseline group to be biased. The author chose to withdraw the first paper and reanalyze the data after excluding random deviation sites; the final results still showed a significant reduction in the incidence of cardiovascular events (31% in the group after supplementation with extra virgin olive oil and in the group after supplementation with mixed nuts 28%).
Attempts to adapt to the Mediterranean diet and find related cardiovascular benefits are now far beyond the borders of the Mediterranean region. Another randomized trial included Indian patients with previous coronary heart disease or high cardiovascular risk. The trial used a so-called "Indo-Mediterranean diet" rich in whole grains, fruits, vegetables, walnuts, almonds, mustard, or soybean oil. High levels of alpha-linolenic acid were obtained and compared with a control group randomly assigned to the Step I National Cholesterol Education Program (NCEP) diet. The cardiovascular mortality rate of patients following the "Indo-Mediterranean diet" was reduced by approximately 60%, and the risk of non-fatal myocardial infarction was reduced by approximately 50%. In a large cohort study of 23,902 British participants for an average of 12.2 years, adherence to the Mediterranean diet was associated with a significant reduction in the incidence of cardiovascular events; the beneficial effects in this study were statistically significant, but not as good as those in PREDIMED Significantly, this may be due to the imperfect and limited transferability of the eating habits contained in the typical Mediterranean diet to the British population. Two cohort studies conducted in the United States confirmed that the incidence of cardiovascular events was also significantly reduced in the American population who adhered to the Mediterranean diet.
At the top of the evidence pyramid, successive meta-analysis of previous cohort studies also acknowledged the association of the Mediterranean diet with reduced cardiovascular morbidity and mortality. A meta-analysis of randomized controlled trials comparing the effects of a Mediterranean diet and a low-fat diet on cardiovascular risk factors showed that the former has an effect on body weight, body mass index, blood pressure, fasting blood sugar, total cholesterol, and high-sensitive C-reactive protein. There is no statistically significant difference in lipoprotein (LDL)-cholesterol and high-density lipoprotein (HDL)-cholesterol levels. Another meta-analysis of randomized controlled trials aimed to find the effect of Mediterranean food patterns on the primary prevention of cardiovascular disease, showing that it has a beneficial effect on total cholesterol and low-density lipoprotein cholesterol levels.
Separate studies have confirmed that adherence to the Mediterranean diet is associated with favorable evolution of abdominal obesity, favorable weight changes, and reduced incidence of overweight and obesity. A systematic review and meta-analysis taking into account several dietary patterns confirmed the protective effect of the Mediterranean diet on the development of type 2 diabetes. Two prospective clinical trials included in this meta-analysis, one in healthy volunteers and the other in patients with a history of myocardial infarction, are specifically designed to evaluate the benefits of the Mediterranean diet in preventing type 2 diabetes. Both trials found that greater adherence to the Mediterranean diet was associated with a reduced risk of diabetes. The sub-analysis in the EPIC study also described the inverse relationship between adherence to the Mediterranean diet and the risk of diabetes. There are few studies on patients diagnosed with type 2 diabetes, mainly cross-sectional and small-scale, which may explain why only some people can prove that the Mediterranean diet is good for evaluating the parameters of blood sugar control, while others are neutral result. However, no harmful effects were found, and the benefits in reducing cardiovascular risk have been confirmed in patients with type 2 diabetes. Nonetheless, several meta-analyses, including clinical trials in patients with diagnosed type 2 diabetes, have also shown that the Mediterranean diet is beneficial for blood sugar control, as assessed by the evolution of plasma glucose and glycosylated hemoglobin (HbA1c) levels.
After research showing the protective effects of the Mediterranean diet on cardiovascular and metabolic diseases, subsequent analysis focused on the possible benefits of other chronic diseases. In the second analysis of the Lyon Diet Heart Study, the first indication is that the Mediterranean diet may have a beneficial effect on cancer incidence and mortality. Several subsequent studies in Swedish and American populations found a reduction in cancer mortality. According to a recent systematic review and meta-analysis, higher adherence to the Mediterranean diet appears to be inversely associated with overall cancer mortality and the risk of colorectal cancer, breast cancer, gastric cancer, liver cancer, head and neck cancer, gallbladder cancer, and cholangiocarcinoma . Another key review showed that the Mediterranean diet reduced the incidence of all gastrointestinal cancers, except for pancreatic cancer. The EPIC study is a large-scale prospective cohort study conducted in 10 European countries, including 521,468 adults, and a 15-year follow-up of various cancer, cardiovascular, metabolic, neurodegeneration, and nutritional results; multiple tasks The group’s research is still ongoing, and it is expected that current or future publications will shed light on ways to connect cancer and nutrition. At present, some people believe that certain components of the Mediterranean diet are closely related to the benefits of primary and secondary cancer prevention.
Some data seem to indicate that the Mediterranean diet has a protective effect on non-alcoholic fatty liver. Higher compliance is associated with lower liver steatosis severity and cross-sectional and some low levels of alanine aminotransferase. Quantity, short-term prospective research. Last but not least, the Mediterranean diet may prevent the development of neurodegenerative diseases. In European and American populations, it has been found that better adherence to the Mediterranean diet is associated with a lower risk of cognitive decline and the development of Alzheimer's disease. A large prospective study of 131,368 participants in the Health Study of Health Professionals and Nurses in the United States showed that the higher the Mediterranean diet compliance score, the lower the risk of Parkinson's disease by 25%. According to a 2014 systematic review and meta-analysis, increased adherence to the Mediterranean diet is associated with a 33% reduction in the risk of mild cognitive impairment or Alzheimer's disease and a decrease in the progression from mild cognitive impairment to clinically apparent Alzheimer's disease related.
The aforementioned data comes from people living in India, the United Kingdom and the United States, and it is not the only attempt to adapt to the Mediterranean diet abroad. Countries in the Mediterranean Basin. A 12-month longitudinal study of healthy male workers in Chile, in which the implementation of the Mediterranean diet in the workplace canteen improved waist circumference, high-density lipoprotein cholesterol and blood pressure, thereby reducing the prevalence of metabolic syndrome by 35% . Another 2-year longitudinal study of obese Israeli workers obtained important weight, triglyceride and total cholesterol reductions in subjects randomly assigned to a calorie-restricted Mediterranean diet; During the additional 4 years of follow-up, total body weight loss was significantly more important than a low-fat, low-calorie diet or a low-carbohydrate diet, thus indicating that these metabolic benefits may stem from better long-term compliance. In a set of studies on American firefighters, this occupation is a high-risk occupation for cardiometabolic diseases. Adherence to the Mediterranean diet is associated with significant improvements in body weight, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol, total weight reduction, and body fat. The prevalence of compartment and metabolic syndrome, as well as higher popularity scores and better compliance among firefighters. The indulgence and attractive lifestyle characteristic of the Mediterranean diet may justify these data. This lifestyle does not completely fast any food group nor does it include calorie counts.
The research trying to decipher the positive influence mechanism of the Mediterranean diet on cardiometabolic, cognitive or tumor risk has covered more and more publications in recent years. Perhaps the best way to explain the benefits of the Mediterranean diet is to view it as one of the best examples of the concept of "food synergy", which is a basic principle of modern nutrition. Various nutrients and foods exhibit multiple interactions and mutually enhance their positive effects. Under this measure, no single food principle can be separated from the background of the entire diet pattern or used as an isolated explanation of the benefits of the Mediterranean diet. In short, the pathways leading to the beneficial effects of the Mediterranean diet on various diseases can be systematized into one or more of the following: lipid-lowering and regulating effects; anti-inflammatory, anti-oxidant and anti-aggregation effects; regulating mediators that are susceptible to cancer, such as Hormones or growth factors; reduce the stimulation of hormones or other extracellular and intracellular transmission pathways involved in the development of metabolic diseases and cancers, due to changes in the amino acid content of the diet, compared with other diets; changes in the intestinal microbiota, promote Changes in bacterial metabolites. A sub-analysis in the PREDIMED trial found that an increase in polyphenol intake was associated with a decrease in all-cause mortality; there was a statistically significant difference between stilbene and lignans, and there was no difference between flavonoids or phenolic acids and total mortality. Significant relationship. Other data from the PREDIMED trial also point to the benefits of eating a lot of olive oil in the diet; adding 10 grams of extra virgin olive oil per day can reduce the incidence of non-fatal cardiovascular events by 10% and reduce cardiovascular mortality by 7% ; In this report, cancer and all-cause mortality were not significantly affected. Olive oil should be understood as not only vegetable fats mainly containing monounsaturated fatty acids such as oleic acid, but also polyunsaturated fatty acids such as linoleic acid. Since olive oil is the main source of dietary fat (because the intake of milk, butter, cream, cheese or meat is significantly reduced in the traditional Mediterranean diet compared to other diets), the use of olive oil in cooking can make saturated fat The total amount reached as low as 8%, sometimes throughout the entire life of an individual. The high content of polyphenols and phytochemicals in olive oil can exert a sustained antioxidant effect and reduce the oxidation of unsaturated fatty acids in its ingredients. In addition, the total antioxidant potential of the Mediterranean diet is accomplished by the phytochemicals in whole grains and the antioxidant vitamins in vegetables and fruits. In addition to olive oil, the healthy balance of fatty acids in the Mediterranean diet is achieved through continuous consumption of nuts, seeds, and whole grains, as well as moderate or large amounts of polyunsaturated fatty acids from fish intake. The high content of plant fiber brought by large amounts of whole grains, beans and fruits can reduce insulin resistance, inhibit the absorption of cholesterol in the intestines and the synthesis of cholesterol in the liver, thereby contributing to overall cardiovascular protection. The plant sterols contained in nuts, whole grains, seeds, vegetables and fruits also help control the absorption of cholesterol in the intestines.
A systematic review of experimental studies investigating the relationship between the Mediterranean diet and the activities of the transcriptome of various organizations found evidence supporting this association, despite the relatively small number of research papers provided. In addition to the anti-inflammatory effects of monounsaturated fatty acids found in virgin olive oil, phenol derivatives in olive oil, such as tyrosol, hydroxytyrosol, bicyclic iridoids, and lignans, seem to affect cells Periodic expression, and terpenes such as oleanolic acid and in animal models, maslinic acid have a regulatory effect on genes that act on the circadian clock.