Cretan Diet

History of the Cretan Diet.

A person’s health is the result of hereditary factors as well as of the influences that it accepts from its environment. Among all the environmental factors that affect the human organism (including smoking, toxins, physical activity etc), the role of nutrition is extremely important as we are constantly exposed to food, throughout our lives. Thus, nutrition is among the most important, if not the most important, environmental factor affecting the human organism. (Ordovas & Corella 2004).

Until quite recently in the history of mankind, different populations were dependent on food that was available in their immediate environment: i.e. foods whose cultivation or availability was favored by the climatic and ecological conditions of each area. Accordingly, different populations have managed to survive and develop in various climatic and ecological conditions, which have respectively led to the formation of different diets and nutritional habits. Different diets, even if they could ensure the good health of people until the age of reproduction, were not necessarily connected with wellness at a later age or with longevity. Thus, during the history of man on earth, there were various ecological, socio-economic and cultural factors which contributed to the formation of different digestive practices in various areas, which did not have, however, the same potential as far as health was concerned. (Willett 2006).

The island of Crete had attracted the attention of the scientific community as early as 1948, when researchers from the Rockefeller Foundation of the United States were summoned by the Greek Government in an attempt to improve, in the post-war era, the “bad” living conditions of the Cretan population. Within this framework, a detailed assessment of the Cretan diet was performed, and –to the surprise of the researchers– it proved to be nutritionally sufficient, with only a few exceptions which were limited to areas with a very low income and very limited food production by the families themselves (Allbaugh et al. 1953). In general, the researchers concluded that “in total, the way of nutrition and the nutritional habits were very well adapted to the natural and economic resources of the area, as well as to the needs of its inhabitants”.

The connection between the diet and the health of the inhabitants of Crete became widely known in later times, with the study of Seven Countries. This study was started shortly before 1960 by the American Acel Keys and his colleagues, due to the impressively low mortality and cardiovascular diseases rates observed in the area. Indeed, according to data of the United Nations, there was no other area in the Mediterranean with such a low percentage as Crete, both before and after World War II (Allbaugh et al. 1953). The study included approximately 13.000 men, which were selected from among 16 different areas of seven countries (Finland, Netherlands, Japan, United States, Italy, Yugoslavia and Greece), in order to examine the, still unclear then, connection between diet and occurrences of cardiovascular disease.

Comparisons conducted between different areas showed that the population of Crete presented the best health status and the lowest mortality rates from coronary disease and cancer compared to all other populations which took part in the study (Keys 1970;Keys et al. 1986; Menotti et al. 1990; Menotti et al. 1999). After 20 years of observation, Cretans demonstrated the lowest death rates from any cause (Menotti et al. 1990), and after 25 years the deaths due to coronary disease in Crete were impressively lower by comparison with deaths occurring in the populations of the United States and Northern Europe, as well as in comparison with other areas of Southern Europe, such as Italy, Yugoslavia, and Corfu (Menotti et al. 1999). As shown in Figure 1, deaths from coronary disease in Italy and Yugoslavia were almost three times greater, while in Corfu they were almost twice those observed in Crete.

Cretan diet or Mediterranean diet?

The traditional diet of people in the Mediterranean was the result of important developments taking place during two millenniums, primarily influenced by the Greeks, the Arabs, the Asians and the Americans (Padilla et al. 2001). Almost 20 countries, with quite a few differences between them, can be characterized as Mediterranean, with their food habits varying due to their religious, economic and cultural particularities. Thereby, the term “Mediterranean diet” can be a little deceptive, since in reality there are not only one but quite a few Mediterranean diets.

The term “Mediterranean diet”, as used today, was in fact introduced by scientists in the food industry to describe the Cretan diet, as well as other diets in various Mediterranean areas which presented common features with it, during the 1950s and the 1960s, when the impact of World War II had faded and the “fast food culture” had not yet appeared. As olive oil constituted the primary source of edible fat in the Cretan diet, the term “Mediterranean diet” describes in fact the nutritional pattern that prevailed in the Mediterranean areas which had been traditionally cultivated with olive trees (Willett et al. 1995).

Health and Cretan Diet.

Based on the Cretan diet, the scientific community in the fields of health and nutrition in the 1960s defined the Mediterranean diet pattern, which has been the object of intensive scientific research during the past years. Results from the studies suggest that individuals who adopt this nutritional pattern present reduced risk against several chronic diseases, while various health indicators are also improved in these individuals. This is particularly important as, according to the World Health Organization, 60% of total deaths worldwide are due to chronic diseases and the adoption of attitudes related to a healthy lifestyle, such as nutrition, can significantly decrease occurrence of these diseases (www.who.int). It is important to note that a healthy lifestyle is related to an 83% decrease in the occurrence of cardiovascular diseases, 91% decrease in the occurrence of diabetes in women and 71% decrease in the occurrence of large intestine cancer in men. Consequently, according to these data, returning to a traditional nutritional pattern should be considered as a necessity for all of us.

Mentioned below are only a few of the many results of studies conducted during the past years regarding the role of what is now referred as the Mediterranean diet in our health. The results displayed derive only from studies which evaluated the Mediterranean diet as a whole, and not based on its individual components.

All the information included applies also to the Cretan diet of 1960s, since the Mediterranean diet was based on it. On the contrary, one could not claim as easily that the diet of other Mediterranean countries during the same period is connected to similar health benefits.

Longevity.

Old age is the result of biological changes occurring by the accumulation of non-reversible damages to the cells of our organism and nutrition is one of the most important factors which affect the course of this process (Canella et al. 2009). The study of Seven Countries, followed by several other ones, was the first to demonstrate that the Cretan, and consequently Mediterranean, diet, contributes to longevity and deceleration of ageing. Individuals who adopt the Mediterranean diet present a longer lifetime, reduced mortality by any cause and particularly reduced mortality due to both coronary disease and cancer (Trichopoulou et al. 2003, Knoops et al. 2004, Trichopoulou et al. 2005, Bamia et al. 2007, Mitrou et al. 2007, Sofi et al. 2008).

Cardiovascular disease.

Cardiovascular diseases are at present the primary cause of death worldwide, and among them coronary disease, with myocardial infarction being its basic clinical onset, which holds the first position (www.who.int). The study of Seven Countries was the first to show the connection between Cretan diet and coronary disease, while these findings were also confirmed by several later studies (Martinez-Gonzalez et al. 2002, Panagiotakos et al. 2008, Fung et al. 2009). Apart from coronary disease and myocardial infarction, the Mediterranean diet has been also proved to have a protective effect against the occurrence of cerebral ischemic attack (Fung et al. 2009). Moreover, the adoption of Mediterranean diet has been connected with lower arterial pressure levels (Psaltopoulou et al. 2004) as well as with reduced occurrence of hypertension in some studies (Panagiotakos et al. 2003).

The adoption of this also appears to be related to lower levels in several indicators which increase the danger of cardiovascular disease, such as homocysteine and inflammation indicator levels (Panagiotakos et al. 2004, Panagiotakos et al. 2005, Salas-Salvado et al. 2007).

Obesity.

According to the World Health Organization 1/3 of adults worldwide can be characterized as hyperbaric and 1/10 as obese (www.who.int). By those rates, obesity appears to be one of the crucial problems of public health, since it is the 6th more important factor in the occurrence of diseases worldwide. Although the connection between the Mediterranean diet and obesity is still under investigation and the conclusions are yet unclear, certain studies demonstrate that individuals who follow the Mediterranean diet weigh less (Schroder et al. 2004, Shubair et al. 2005, Panagiotakos et al. 2006) and present a lower fat storage in the abdominal area (Panagiotakos et al. 2006). The above mentioned is particularly important since the accumulation of intestinal fat is a crucial factor in the danger of occurrence of metabolic disorders which can lead to diabetes and cardiovascular diseases. Furthermore, the adoption of this diet has appeared to be related to a decrease in the rate of weight gain and in the occurrence of obesity over the years. (Sanchez-Villegas et al. 2006, Mendez et al. 2006).

Type 2 diabetes and metabolic syndrome.

The increased rates of obesity observed during the past years have lead to respectively increased rates of metabolic syndrome and diabetes (Gregg et al. 2005). Metabolic syndrome is now a very common disorder which increases the possibility of diabetes and cardiovascular disease, and is characterized by central obesity, increased glucose levels, increased triglycerides levels, increased arterial pressure levels and low HDL cholesterol levels (Alberti et al. 2006). The adoption of the Mediterranean diet has been connected with reduced occurrence of metabolic syndrome (Panagiotakos et al. 2004, Rumavas et al. 2009, Babio et al. 2009), and diabetes (Martinez-Gonzalez et al. 2008). Furthermore, in diabetic patients, the adoption of the Mediterranean diet has been connected with a better control of the disease (Esposito et al. 2009), while in patients who have just been diagnosed with diabetes it appears to delay the beginning of the pharmaceutical treatment. (Esposito et al. 2009).

Cancer.

The adoption of the Mediterranean diet appears to be connected with decreased occurrence of cancer in general (Benetou et al. 2008), as well as with decreased occurrence of specific forms of cancer. It is thus connected with decreased occurrence of cancer in the upper respiratory tract and more specifically in oral cavity, pharynx, (Fransceschi et al. 1999), oesophagus (Bosetti et al. 2000) and larynx (Bosetti et al. 2002). Moreover, it seems to be connected to reduced occurrence of breast cancer (Murtaugh et al. 2008, Cottet et al. 2009) and colorectal cancer (Reedy et al. 2008).

It has been estimated that over 25% of colorectal cancer cases, over 15% of breast cancer cases and over 10% of cases of cancer of the prostate, pancreas and endometrium could be prevented by the adoption of the traditional Mediterranean diet (Trichopoulou et al. 2000).

Alzheimer’s and Parkinson diseases.

Recent studies suggest that the Mediterranean diet is also connected to the onset of Alzheimer’s and Parkinson diseases, whose frequency has been increased during the past years. The adoption of the Mediterranean diet has been proved to reduce occurrence of both these disorders, as well as mortality by Alzheimer’s disease (Scarmeas et al. 2006, Scarmeas et al. 2007, Sofi et al. 2008).