Med Diet & Health
Scientists have intensely studied the eating patterns characteristic of the Mediterranean Diet for more than half a century.
Shortly after World War II, Ancel Keys and colleagues (including Paul Dudley White, later President Eisenhower's heart doctor) organized the remarkable Seven Countries Study to examine the hypothesis that Mediterranean-eating patterns contributed directly to improved health outcomes. This long-running study examined the health of almost thirteen thousand middle-aged men in the United States, Japan, Italy, Greece, the Netherlands, Finland, and then-Yugoslavia.
When the data were examined, it was clear that people who ate a diet where fruits and vegetables, grains, beans, and fish were the basis of daily meals were healthiest. Topping the chart were residents of Crete. Even after the deprivations of World War II – and in part, perhaps, because of them – the cardiovascular health of Crete residents exceeded that of US residents. Researchers attributed the differences to diet.
Out of this extensive work came an understanding that certain Mediterranean-eating patterns were remarkably connected with good health. From this conclusion emerged the concept of a "Mediterranean Diet" that could promote lifelong good health.
In subsequent years the body of scientific evidence supporting the healthfulness of the traditional Mediterranean Diet has continued to grow. Oldways tracks this research and shares it in two ways:
1) Med Diet in the News. We regularly post summaries of the latest research on our Health Studies page. Check there at least once a month, to learn about recent studies.
2) Overview of the Med Diet's Health Benefits. For those who are new to the health benefits of the Mediterranean Diet, it can be helpful to get the big picture. The following excerpts from a selection of leading medical and health journals demonstrate the enormous amount of evidence supporting the "gold standard" status of traditional Mediterranean eating patterns, which have been shown to:
Greater adherence to a Mediterranean diet is associated with a significant improvement in health status, as seen by a significant reduction in overall mortality (9%), mortality from cardiovascular diseases (9%), incidence of or mortality from cancer (6%), and incidence of Parkinson's disease and Alzheimer's disease (13%). These results seem to be clinically relevant for public health, in particular for encouraging a Mediterranean-like dietary pattern for primary prevention of major chronic diseases.
These results provide strong evidence for a beneficial effect of higher conformity with the Mediterranean dietary pattern on risk of death from all causes, including deaths due to CVD and cancer, in a US population.
The findings of this study in a northern European population of young women indicate that closer adherence to a Mediterranean dietary pattern reduces mortality even among young persons.
In this large, population-based cohort study, we found that a higher degree of adherence to the traditional Mediterranean diet was associated with a reduction in total mortality (17%) ... with respect to both deaths due to coronary heart disease and deaths due to cancer.
Trichopoulou et al. report the results of a population-based study involving 22,043 apparently healthy adults in Greece, in which adherence to a traditional Mediterranean diet was associated with significantly lower total mortality, mortality from coronary heart disease, and mortality from cancer.
Adherence to the principles of the traditional Mediterranean diet is likely to be associated with lower overall mortality. Moreover, key features of this diet appear to be transplantable to other dietary cultures and cuisines, and may have a substantial beneficial impact on the general mortality of elderly people who have the Westernized dietary habits. We conclude that a diet that adheres to these principles of the traditional Mediterranean diet is associated with longer survival.
Eating a Mediterranean-style diet rich in olive oil, whole grains, fish and fruit may protect aging brains from damage associated with cognitive problems. After reviewing brain MRI's of 712 octogenarians, researchers found that those following the Med Diet the most closely were up to 36% less likely to show brain damage from small strokes.
Nikolaos Scarmeas, M.D, associate professor, clinical neurology, Taub Institute, Columbia University Medical Center, New York City; Connie Diekman, R.D., director, university nutrition, Washington University in St. Louis; scheduled presentation, American Academy of Neurology annual meeting, Toronto, April 10-17, 2010
Defend you from chronic diseases
A Mediterranean diet pattern, high in plant-based foods and with healthful unsaturated:saturated fat ratio, is associated with lower abdominal obesity. This can reduce the risk of developing coronary heart disease.
We compared the 1-year effect of 2 behavioral interventions to implement the Mediterranean Diet vs. advice on a low-fat diet on Metabolic Syndrome status. A traditional Mediterranean Diet enriched with nuts could be a useful tool in the management of the Metabolic Syndrome.
... our findings emphasize the importance of the consumption of a dietary pattern "close" to the Mediterranean diet and the adoption of even light-to-moderate physical activity to reduce the prevalence of the metabolic syndrome at the population level.
These results provide strong evidence for a beneficial effect of higher conformity with the Mediterranean dietary pattern on a risk of death from all causes, including deaths due to CVD and cancer in a US population.
During the past decades a large body of evidence has related adherence to a Mediterranean diet with reductions in all-cause mortality, the prevalence of metabolic disorders such as obesity and high blood pressure, and the incidence of coronary heart disease and various types of cancer.
Adherence to a Mediterranean diet is associated with reduced odds of having hyper-cholesterolemia, hypertension, diabetes and obesity among elderly people.
Together with regular physical activity and not smoking, our analyses suggest that over 80% of coronary heart disease, 70% of stroke, and 90% of type 2 diabetes can be avoided by healthy food choices that are consistent with the traditional Mediterranean Diet.
Patients who followed a Mediterranean-type diet had reduced combined all-cause mortality, nonfatal cancer, and myocardial infarction compared with those who followed an approximate American Heart Association Step 1 diet. The Mediterranean-type diet also showed a trend toward a decreased risk for cancer.
The Mediterranean diet or its elements have repeatedly been shown to provide remarkable protection against chronic diseases.
Efforts to combat nutrient deficiencies have centered on supplemental nutrient administration and addition of selected nutrients to the food chain in the form of food fortification. In addition to supplementation or fortification with specific nutrients, the consumption of certain dietary patterns (such as the Mediterranean diet) is associated with a reduced risk of chronic diseases, particularly cardiovascular diseases."
Greater adherence to a relative Mediterranean diet is associated with a significantly lower risk for incident gastric adenocarcinoma (stomach cancer), according to the results of a prospective cohort study
Buckland G, Agudo A, Luján L, Jakszyn P, Bueno-de-Mesquita HB, Palli D, Boeing H, Carneiro F, Krogh V, Sacerdote C, Tumino R, Panico S, Nesi G, Manjer J, Regnér S, Johansson I, Stenling R, Sanchez MJ, Dorronsoro M, Barricarte A, Navarro C, Quirós JR, Allen NE, Key TJ, Bingham S, Kaaks R, Overvad K, Jensen M, Olsen A, Tjønneland A, Peeters PH, Numans ME, Ocké MC, Clavel-Chapelon F, Morois S, Boutron-Ruault MC, Trichopoulou A, Lagiou P, Trichopoulos D, Lund E, Couto E, Boffeta P, Jenab M, Riboli E, Romaguera D, Mouw T, González CA. American Journal of Clinical Nutrition. Adherence to a Mediterranean diet and risk of gastric adenocarcinoma within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study. Published online ahead of PMID: 20007304.
Adding as little as 10 teaspoons of olive oil to your daily diet could help protect women against breast cancer, Spanish researchers say. The findings show that olive oil mounts a multi-pronged attack on cancer tumours, stunting their growth, driving their cells to implode and protecting against potentially cancerous damage to DNA.
Source: Journal of the Federation of American Societies for Experimental Biology (FASEB)
A study following 65,374 women reported that eating a Mediterranean diet can reduce the risk of postmenopausal breast cancer when caloric intake remains within recommendations.
V Cottet, M Touvier, A Fournier, M Touillaud, L Lafay, F Clavel-Chapelon, MC Boutron-Ruault. Postmenopausal Breast Cancer Risk and Dietary Patterns in the E3N-EPIC Prospective Cohort Study. American Journal of Epidemiology. Published online ahead of print: DOI: 10.1093/aje/kwp257.
Data presented from a review of 20,000 cases affecting 20 cancer sites and 18,000 controls show that risk for most epithelial cell cancers was decreased with increased fruit, vegetable, whole grain and fish intake. Olive oil and other monounsaturated and unsaturated fats were inversely related to cancer risk at several sites. A Mediterranean diet pattern appears to be favorable for reduced cancer risk.
La Vecchia C. Association between Mediterranean dietary patterns and cancer risk. [Review] Nutrition Reviews. 2009; 67(5):126-130.
The Mediterranean diet is not a specific diet plan or diet program but a collection of eating habits that are traditionally followed by the people of the Mediterranean region. There are at least 16 countries bordering the Mediterranean Sea and food habits vary between these countries according to culture, ethnic background and religion. The Mediterranean diet, containing olive oil, fish, fruits and vegetables is associated with a low rate of cardiovascular and cancer diseases.
...an optimal diet for the prevention of both coronary heart disease and cancer is likely to extensively overlap with the traditional Mediterranean diet. It is not yet clear which components in the Mediterranean diet are more important for its apparent health effects, but olive oil, plant foods and moderate wine consumption are likely candidates.
The PERDIMED (Prevención con Dieta Mediterránea) study is a multi-center randomized clinical trial to determine the efficacy of the Mediterranean Diet on the primary prevention of cardiovascular disease. 1224 participants already involved in this study were recruited to either consume a Mediterranean diet and either 30g of nuts daily or 1L of olive oil weekly. Individuals who met the criteria for metabolic syndrome at the beginning of the trial showed a decreased prevalence in metabolic syndrome after one year of eating a Mediterranean diet plus 30g of nuts per day. Previous analyses of the data have shown that the Mediterranean diet coupled with nuts protects against oxidative damage and reduces cardiovascular risk factors better than a traditional low-fat diet.
Salas-Salvadó J, Fernández-Ballart J, Ros E, et al. Effect of a Mediterranean diet supplemented with nuts on metabolic syndrome status. Arch Intern Med. 2008;168:2449-2458.
We identified strong evidence of a causal relationship for protective factors, including intake of vegetables, nuts and monounsaturated fatty acids and Mediterranean, prudent and high-quality dietary patterns. The Mediterranean diet, rich in omega-3 fatty acids, and vitamins C, E and folate, is the only dietary pattern associated with a lower risk for heart disease.
A. Mente, L. de Koning, H.S. Shannon, S.S. Anand. A Systematic Review of the Evidence Supporting a Casual Link Between Dietary Factors and Coronary Heart Disease.
Our results suggest that adhering to a Mediterranean-type diet could contribute to the prevention of age-related changes in blood pressure.
Consuming a Mediterranean-type diet rich in fruits, vegetables, and low-fat dairy products and reduced in sodium and saturated fat represents an ideal eating pattern. Weight loss and increased physical activity contribute to ideal lifestyle conditions.
Experimental and epidemiological studies indicate that eating patterns, such as the traditional Mediterranean or Okinawan diets, that incorporate these types of foods and beverages reduce inflammation and cardiovascular risk. This anti-inflammatory diet should be considered for the primary and secondary prevention of coronary artery disease and diabetes.
Our results suggest that the more frequent consumption of foods from the Mediterranean pattern may reduce cardiovascular disease and ischemic heart disease risks and may be most beneficial for persons with diabetes.
Individuals at high cardiovascular risk who improved their diet toward a traditional Mediterranean Diet (TMD) pattern showed significant reductions in cellular lipid levels and LDL oxidation. Results provide further evidence to recommend the TMD as a useful tool against further risk factors for coronary heart disease.
Our results suggest that the healthy effects of the Mediterranean Diet observed in epidemiologic studies are exerted partly through plausible mechanisms: improved lipid profiles and reductions in blood pressure, insulin resistance, and systemic markers of inflammation...An increasing body of knowledge supports the Mediterranean diet as a useful tool in managing individuals who are at high risk for CHD (coronary heart disease).
The SUN study and the accompanying case-control study support the benefits of a Mediterranean diet and olive oil against coronary heart disease and hypertension.
The present study provides a pathophysiologic explanation to the growing scientific evidence for the beneficial effect of the Mediterranean diet on human health and, especially, atherosclerotic disease. We found that greater adherence to this traditional diet was independently associated with a reduction in the inflammation and coagulation indexes that are believed to have an important role in CVD. The World Health Organization reports that the three major components involved in preventing atherosclerotic disease are smoking, physical inactivity, and an unhealthy diet, as they are factors that can be changed. Our findings emphasize the need for actions from public health care professionals in order to prevent the development and progression of atherosclerotic diseases through the adoption of low animal fat diets, like the Mediterranean diet.
In the Lyon Heart Study, higher ALA [a type of healthy fat] consumption in the context of a Mediterranean diet dramatically reduced total and cardiovascular mortality as well as nonfatal myocardial infarctions. These trials strongly support the protective effects of omega-3 fatty acids, including both ALA and fish oil, in secondary prevention of CHD. Mediterranean diet enriched with ALA reduced death by more than 70 percent.
The traditional Mediterranean diet as outlined in this article is an ideal eating pattern for prevention of cardiovascular disease. We believe that current understanding and scientific evidence are adequate to recommend this diet widely as a practical, effective, and enjoyable strategy—the new "gold standard"—in heart disease prevention.
Eating a diet with omega-3 fatty acids can improve insulin sensitivity.
Abete, I., D. Parra, A.B. Crujeiras, E. Goyenechea, and J.A. Martinez. "Specific insulin sensitivity and leptin responses to a nutritional treatment of obesity via a combination of energy restriction and fatty fish intake." Journal of Human Nutrition and Dietetics 21.6 (Dec 2008): 591(10).
Adherence to a Mediterranean diet is associated with a reduced risk of diabetes.
The lower risk associated with a Mediterranean-type diet suggests that diet could help reduce incidence of pre-diabetes after a myocardial infarction. Many, though not all, trials have indicated that a Mediterranean-type diet lowers risk factors linked to insulin resistance and diabetes, including serum triglycerides, HDL cholesterol, systemic inflammation, endothelial function, and insulin sensitivity.
Several mechanistic links offer potential explanations of the Mediterranean diet's protective effect on obesity and type 2 diabetes. High consumption of vegetables, fruits, legumes, nuts, fish, cereals and olive oil, together with moderate consumption of alcohol, predominantly, wine, leads to high ingestion of dietary fiber, antioxidants, magnesium and unsaturated fatty acids. Additionally, this diet is characterized by a low degree of energy density overall, which might be particularly important for the prevention of weight gain.
Replacing saturated fats with monounsaturated fats (MUFA) in a diet is a healthy alternative to a low-fat, high carbohydrate diet in overweight individuals with type 2 diabetes. High-MUFA diets (20% of total fat as MUFA) are typical of the Mediterranean region and emphasize vegetables, fruits, whole grains, legumes, nuts and olive oil. Our study results suggest that high-MUFA diets can replace conventional lower-fat diets without a negative impact on body weight, body composition, cardiovascular risk factors, or glycemic control.
Brehm, B J, Lattin, B L, Summer, S S, Boback, J A, Gilchrist, G M, Jandacek, R J, & D'alessio, D A. One-year comparison of a high-monounsaturated fat diet with a high-carbohydrate diet in type 2 diabetes. Diabetes Care. 2009; 32(2): 215-16.
Mediterranean and low-carbohydrate diets may be effective alternatives to a low-fat diet. Consumption of monounsaturated fats is thought to improve insulin sensitivity, an effect that may explain the favorable effect of the Mediterranean diet on glucose and insulin levels.
We found that a simple but targeted nutrition intervention promoting the Mediterranean food pattern can be effective in modifying food habits and can contribute to a reduction of energy density of the diet. The current study also shows that the adoption of a Mediterranean food pattern in a North American context can be achieved without significant increase in food cost or food energy.
The main finding of this study is that high adherence to the traditional Mediterranean dietary pattern, characterized by high intakes of vegetables, fruits, legumes, fish, cereals, and nuts and low and moderate consumption of meat and wine, respectively, is associated with a lower prevalence of obesity in men and women in this Mediterranean population. This association held even after controlling for age, leisure time physical activity, educational level, smoking, and alcohol consumption.
Long-term success in weight loss with dietary treatment has been elusive. A moderate-fat, Mediterranean-style diet, controlled in energy, offers an alternative to a low-fat diet with superior long-term participation and adherence, with consequent improvements in weight loss.
Keep away depression
The adherence to a Mediterranean Dietary Pattern ensures an adequate intake of fruits, nuts, vegetables, cereals, legumes or fish, important sources of nutrients linked to depression prevention.
When combined with physical activity on a regular basis, adhering to a Mediterranean diet pattern can reduce the risk of developing Alzheimer's disease by 48 percent.N. Scarmeas, J. Luchsinger, N. Schupf, A. Brickman, et al. Physical activity, diet and risk of Alzheimer disease. JAMA. 2009;302(6):627-637.
Higher adherence to the Mediterranean diet is associated with a trend for reduced risk of developing Mild Cognitive Impairment and with reduced risk of Mild Cognitive Impairment conversion to Alzheimer Disease.
Adherence to the Mediterranean diet (MeDi) may affect not only risk for Alzheimer disease (AD) but also subsequent disease course: Higher adherence to the MeDi is associated with lower mortality in AD. The gradual reduction in mortality risk for higher MeDi adherence tertiles suggests a possible dose-response effect.
The Mediterranean Diet... has been associated with lower risk for several forms of cancer, obesity, dyslipidemia, hypertension, abnormal glucose metabolism, coronary heart disease, and overall mortality. In a recent study, we demonstrated that higher adherence to the Mediterranean Diet at baseline evaluation was associated with lower risk of developing Alzheimer's disease during follow-up. Similarly to our previous findings, in this different Alzheimer's disease population we observe that higher adherence to the Mediterranean Diet is associated with reduced disease odds. Similarly to our previous report, we note a gradual reduction in Alzheimer's disease risk for higher tertiles of Mediterranean Diet adherence, suggesting a possible dose-response effect. Additionally, in accordance with our previous results, the associations between Mediterranean Diet and Alzheimer's disease remain unchanged and significant even when simultaneously adjusting for the most commonly considered potential confounders for Alzheimer's disease, such as age, sex, ethnicity, education, APOE genotype, caloric intake, and BMI. Higher adherence to Mediterranean Diet reduced risk for probable Alzheimer's disease either with or without coexisting stroke.
Recent findings showing that elderly African Americans and Japanese living in the USA have a much higher prevalence of Alzheimer's disease (6.24% and 4.1%, respectively) than those still living in their ethnic homelands (< 2%) suggest that the prevalence of Alzheimer's disease is more strongly influenced by diet and nutrition, environment and/or lifestyle than by genetics... In conclusion, the Mediterranean diet pattern based on complex carbohydrates, fibre and non-animal fat appears to protect against age-related cognitive decline and cognitive decline of vascular or degenerative origin.
In conclusion, the results of this large prospective study suggest that dietary patterns with high intake of fruit, vegetables, legumes, whole grains, nuts, fish, and poultry and a low intake of saturated fat and a moderate intake of alcohol may protect against PD [Parkinson's disease].
Diet is associated with wheeze and asthma but not with allergic sensitisation in children. These results provide further evidence that adherence to the ‘Mediterranean diet’ may provide some protection against wheeze and asthma in childhood.
Gabriele Nagel, Gudrun Weinmayr, Andrea Kleiner, Luis Garcia-Marcos, David P Strachan, the ISAAC Phase Two Study Group; Institute of Epidemiology, Ulm University, Helmholtzstr April 6, 2010
High adherence to traditional Mediterranean diet increased the likelihood of asthma to be under control in adults.
Our results support a protective effect of a high level of adherence to the Mediterranean Diet during pregnancy against asthma-like symptoms and atopy in childhood.
In the large prospective cohort of US men, two distinct dietary patterns were identified using principal component analysis: the prudent [Mediterranean-style] pattern (loaded by a high consumption of fruits, vegetables, fish and whole grains) and the Western pattern (loaded by a high intake of refined grains, cured and red meats, desserts and sweets and French fries). During 12 years of follow-up, the risk of newly diagnosed chronic obstructive pulmonary disease (COPD) decreased as the prudent [Mediterranean-style] pattern score increased, whereas the risk of newly diagnosed COPD increased as the Western pattern score increased.
We showed a general protective effect of a high level of adherence to the Mediterranean diet on allergic rhinitis, asthma and atopy.
The Mediterranean dietary pattern seems to be associated with reduction in the risk of offspring being affected by spina bifida.
Nearly a third of babies born in India are low birth weight (LBW). Researchers followed 676 women there to explore if low seafood consumption is a risk factor for LBW. Women who did not eat fish during the third trimester had a significantly higher risk of LBW. One possible reason for this is the omega-3s fatty acids in fish may speed up how fast a baby grows by increasing blood flow to the placenta.
S. Muthayya, et al. St. John’s National Academy of Health Sciences, Bangalore, India
European Journal of Clinical Nutrition, March 2009
The children of women who ate fish two or more times per week while pregnant revealed higher cognitive scores than the children whose mothers ate less than 2 servings per week or none at all.
A Mediterranean diet reduces the risk of the most common cause of poor eyesight in older people, A new study by the Centre for Eye Research Australia (CERA) found that people who consume at least 100 millilitres of olive oil a week are almost 50 per cent less likely to develop macular degeneration than those who eat less than 1 millilitre per week.
Source: Centre for Eye Research Australia. CERA is affiliated with the University of Melbourne and the Royal Victorian Eye and Ear Hospital, where it is based. Report author: Dr Elaine Chong
Omega-3 fatty acids of marine and plant origin were found to have strong anti-bacterial activity against a range of oral pathogens, according to findings published in Molecular Oral Microbiology.
EPA (eicosapentaenoic acid), DHA (docosahexaenoic acid) and ALA (alpha-linolenic acid), as well as their fatty acid ethyl esters could inhibit the growth of oral pathogens, including Streptococcus mutans, Candida albicans, and Porphyromonas ginigivalis at relatively low doses.
Source: Molecular Oral Microbiology Volume 25 Issue 1, Pages 75 – 80 “A novel bioactivity of omega-3 polyunsaturated fatty acids and their ester derivatives” Authors: C.B. Huang, J.L. Ebersole
To investigate associations between preconception dietary patterns and infertility treatment outcomes, researchers followed 161 couples in Netherlands undergoing fertility treatment. It was found that the one-third of women who scored highest in adherence to the Mediterranean diet had a pregnancy rate of 30 percent following IVF or ICSI.
Journal of Fertility and Sterility Feb. 2010 Vujkovic M, de Vries JH, Lindemans J, Macklon NS, van der Spek PJ, Steegers EA, Steegers-Theunissen RP. Department of Obstetrics and Gynecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
For more excerpts from medical and scientific journals, please contact Georgia Orcutt.