The Health Benefits of Olive Oil

“Should I cease giving my oil, with which they honor God and men?” —Judges 9:9

Olive oil has been used since ancient times in food preparation and for other purposes, such as lamps or as an ointment. In the Bible, olive oil is mentioned as a blessing for those who consume it. In the book of Deuteronomy we read God’s pledge regarding the Promised Land:

“For the LORD your God is bringing you into a good land, a land of brooks of water, of fountains and springs, that flow out of valleys and hills; a land of wheat and barley, of vines and fig trees and pomegranates, a land of olive oil and honey…” —Deuteronomy 8:7-8, NKJV.

It is very likely that olive oil was used in preparation of manna, as alluded to in the following passage:

“Now the manna was like coriander seed, and its color like the color of bdellium. The people went about and gathered it, ground it on millstones or beat it in the mortar, cooked it in pans, and made cakes of it; and its taste was like the taste of pastry prepared with oil,” —Numbers 11:7-8, NKJV.

In biblical times, olive oil was derived by crushing olives with large stones, collecting the crushed olives and placing them under large stones to be squeezed. Olive oil would then flow into a basin below the crushing and squeezing area. The pictures below show a method of crushing olives (on the left) and stones used to squeeze the olives (on the right) to derive olive oil in ancient Israel.

Nutritional profile of olive oil

Olive oil contains mainly monounsaturated fatty acids. In one tablespoon of extra virgin olive oil, there are 10 grams of monounsaturated, two grams of saturated, and two grams of polyunsaturated fatty acids. Olive oil is also a relatively good source of two fat-soluble vitamins, vitamins E and K, and provides approximately 10 percent of the daily value per tablespoon. In addition to the fatty acid content, olive oil contains a variety of compounds called the phenolic compounds. In fact, no less than 66 different phenolic compounds have been identified. Phenolic compounds influence the color and taste of foods, among other things.

Many health effects of olive oil have been attributed more to its phenolic compounds content than its composition of different type of fatty acids. Several factors play a role in the content of these beneficial compounds in olive oil. They include the type of cultivar used, region where the trees are grown, age of the trees, olive storage conditions, stage of maturation of olives, type of processing, storage conditions, and heat. The phenolic compounds found in olive oil have been shown to have anti-oxidative, anti-inflammatory, anti-microbial, and anti-carcinogenic activities.

What are the health effects of olive oil?

Of all the oils available in grocery stores, olive oil is one of the most beneficial to human health. Research clearly shows that the use of olive oil helps reduce the risk of many chronic diseases such as heart disease, cancer, stroke, and hypertension. For example, a study published in the medical journal Archives of Internal Medicine showed that olive oil is effective in reducing blood pressure. In this experiment, patients were divided into two groups. One group was instructed to add olive oil to their diet (men: 4 tablespoons; women: 3 tablespoons), and the other group was advised to add the same amount of sunflower seed oil. After six months, 8 of the 11 patients who consumed olive oil no longer needed to take antihypertensive medications. However, none of those who ingested the sunflower seed oil discontinued using medications.

In a large Italian study of 29,689 women who were followed for almost eight years, those with the highest intake of olive oil, compared to those with the lowest intake, had a statistically significant 44 percent lower risk of coronary heart disease. In another study with more than 40,000 participants from Spain, intake of 10 grams (about 1/3 of an ounce) of olive oil was associated with 7 percent lower risk of coronary heart disease. Consequently, experts on the health effects of olive oil state that “exclusive use of olive oil during food preparation seems to offer significant protection against CHD [coronary heart disease], irrespective of various clinical, lifestyle and other characteristics of the participants.”

Research findings also indicate that olive oil can help reduce risk of some types of cancer. One such study was carried out with 755 women living in the Canary Islands. The women who consumed the highest amount of olive oil had a 48 percent lower risk of developing breast cancer compared to women consuming the least amount of olive oil. A study conducted in Italy and Switzerland assessed the impact of olive oil consumption on the risk of developing cancer of the colon (large intestine) and rectum. In this research, scientists assessed risk based on the amount of olive oil used in frying. From other studies, it is known that carcinogenic compounds, e.g. oxygen radicals, can develop when fats and/or oils are heated to a high temperature. Researchers compared the risk among 886 individuals with cancer to 4,765 individuals without cancer. The results indicated that olive oil users had a reduced cancer risk of 11 percent.

Another study conducted in Greece showed that those with the greatest long-term consumption of olive oil (consumption almost every day in a lifetime) had about 4 times lower risk of developing arthritis compared to those who consumed olive oil, on average, only about six times per month. The same researchers showed that increasing the consumption of olive oil to two times a week, reduced the risk of developing arthritis by half. Olive oil may also offer some protection against bone fractures. A study published in the European Journal of Clinical Nutrition conducted in Spain showed that people who had the greatest ratio of olive oil to omega-6 had an 80 percent reduced risk of fractures.

At a conference about the impact of olive oil on human health held in Cordoba in Spain, an organization called Centro de Excelencia Foundation sobre Aceite de Oliva y Salud stated that the use of olive oil reduces the risk of cardiovascular disease, probably protects against age-related decline in cognitive abilities and Alzheimer's disease, and is associated with healthier aging and longevity. In the conference’s report we also read: “The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life.”

Additionally, according to the recommendations of the Advisory Committee of the American Heart Association, “a diet high in MUFA [monounsaturated fatty acids — olive oil predominantly contains this type of fat] (versus a high-carbohydrate diet) improves glycemic control in individuals with NIDDM [non-insulin-dependent diabetes mellitus] who maintain body weight. Individuals with elevated triglycerides or insulin levels also may benefit from a high-MUFA diet.”

Is it true that olive oil detrimentally impacts arterial walls?

In recent years, some prominent advocates of vegan diets have claimed that the use of virgin olive oil detrimentally effects the epithelial cells of arteries, thus increasing risk of atherosclerosis. For that reason, the same individuals advocate the use of virtually no oil of any kind, including no olive oil in cooking or food preparation. Arterial walls are composed of three distinct layers. The most inner of these layers is called intima. This layer is lined with specialized epithelial cells called endothelial cells also referred to as the endothelium. The structure of arteries is illustrated below.

When endothelium gets damaged or when the endothelial cells die, the atherosclerotic process begins. Any factor that damages or cause these cells to die may increase risk of cardiovascular disease. Damaged endothelium triggers an inflammatory reaction (as is the case with any cuts on skin). Scientists are able to measure a degree of inflammation by assessing the levels of such compounds as C-reactive protein and cytokines (mainly a specific type of cytokines called interleukin-6).

The claim that virgin olive oil damages the endothelium is based on selectively picked findings. To date, a number of studies assessed the impact of olive oil on arterial function and structure. In 2015, a team of scientists from Austria and Germany published a meta-analysis of findings from 30 different studies based on 3,106 participants. A meta-analysis is a specific tool scientists use to evaluate and summarize findings of more than one study in order to assess their combined effect. The following is the conclusion these scientist reached: “Olive oil interventions (with daily consumption ranging approximately between 5 to 50 g) resulted in a significantly more pronounced decrease in C-reactive protein (mean difference: -0.64 mg/L, (95% confidence interval (CI) -0.96 to -0.31), p < 0.0001, n = 15 trials) and interleukin-6 (mean difference: -0.29 (95% CI -0.7 to -0.02), p < 0.04, n = 7 trials) as compared to controls, respectively.” A decrease in either C-reactive protein or interleukin-6 indicates a lower level of inflammation, which means healthier endothelium, better arterial function and lower risk of heart disease.

Similarly, scientists are capable of assessing the function of arteries by measuring how much blood is able to flow through them. Lower blood flow usually indicates a narrowing of arteries due to plaque formation inside the arterial walls. Assessment of blood flow is referred to as “flow-mediated dilatation” also sometimes called “flow-mediated vasodilatation.” In the above-mentioned meta-analysis, the authors stated, “Values of flow-mediated dilatation (given as absolute percentage) were significantly more increased in individuals subjected to olive oil interventions (mean difference: 0.76% (95% CI 0.27 to 1.24), p < 0.002, n = 8 trials).” An increase of blood flow indicates less atherosclerosis in the arteries and wider arterial lumen. Consequently, these researchers stated, “These results provide evidence that olive oil might exert beneficial effects on endothelial function as well as markers of inflammation and endothelial function, thus representing a key ingredient contributing to the cardiovascular-protective effects of a Mediterranean diet.” Thus, a conclusion that olive oil damages arterial endothelium is inconsistent with the best available evidence.

Is it true that olive oil should not be heated?

One of the most common questions asked about olive oil is regarding its use in frying and baking. This is because in some sources, including many websites, one can find information that olive oil should not be used for frying or baking due to the fact that this oil has relatively low smoking and burning temperatures. According to the International Olive Oil Council, the smoke temperature of olive oil is 210 degrees C (410 F), and according to the Institute of Shortening and Edible Oils, it is 215 degrees C (420 F). In comparison, the smoke temperature of canola seed oil is approximately 205 degrees C (400 F). Smoke temperatures of oils and fats have been known for many decades. In 1940, two scholars, Detwiler and Markley, published oil burning temperatures in the Journal of the American Oil Chemists Society. The smoke and burning temperatures of selected oils are included in the table below. The values are based on the above mentioned publication.

As can be seen from values found in the table, smoke and burning temperatures of olive oil are comparable to those of other commonly used oils. Based on this data, it can be concluded that olive oil can be used in place of other vegetable oils for frying, baking, and other kinds of food preparation.

Table 1: The smoke and burning temperatures of selected oils

What is the difference between olive oil and extra virgin olive oil?

There are several types of olive oil available in grocery stores. Several of these are listed and described in the table below. The main difference between them has to do with the production method of these oils. The process of production also affects the content of bioactive compounds found in these oils. Similarly, the olive oils differ somewhat in terms of the chemical structure of the oil. In nature, the bulk of fats and oils come in a form of triglycerides. Triglycerides are compounds composed of a glycerol backbone with three attached fatty acids. A simplified structure of triglycerides is depicted below.

Due to the exposure to environmental factors, such as temperature or sunshine, fatty acids may become detached from the glycerol backbone. The more fatty acids get detached from glycerol, the more acidic the oil becomes (the acidification of the oil is called rancidity). The term “virgin” means that it has been derived by mechanical pressing of olives without any use of chemicals or temperature. The term “extra” as in “extra virgin” refers to the oil’s acidity or the content of free floating (detached from glycerol) fatty acids. Thus, “extra virgin olive oil” means that the oil was obtained by mechanical pressing of olives without the use of temperature or solvents. It also means that it has lower acidity than virgin olive oil and higher acidity than extra, extra virgin olive oil. The health effects of olive oil described above refer to olive oil that has been obtained by mechanical pressing (e.g. virgin olive oil, extra virgin olive oil, etc.). Olive oil that has been obtained by heat and/or the use of chemical solvents may not have the same health effects, mainly because of lower content of phenolic compounds. The table below contains a list of different types of olive oils available in grocery stores along with their description.

Table 2: Characteristics of different types of olive oil

Summary and recommendations

Virgin olive oil has been used in food preparation since ancient times. Virgin olive oil offers several health benefits, including lower risk of cardiovascular disease and reduced risk of some cancers. These benefits are a result of the nutritional profile of olive oil, mainly the content of phenolic compounds. Olive oil enhances the flavor of food, and it can be used raw and in cooking, baking or frying. Although olive oil is considerably more expensive than most other types of plant-derived oils, it seems to be a good investment in our health since it offers health benefits that are not obtained by using other types of oils.

Notes & References:

Delgado-Rodríguez M. Dietary fat intake and the risk of osteoporotic fractures in the elderly. European Journal of Clinical Nutrition, 2007;61:1114–1120.

Detwiler S., Markley K. Smoke, flash, and fire points of soybean and other vegetable oils. U.S. regional soybean industrial products laboratory. Urbana, IL.

Dybkowska E., Waszkiewicz-Robak B., Świderski F. Assessment of n-3 and n-6 polyunsaturated fatty acid intake in the average Polish diet. Polish Journal of Food and Nutrition Science, 2004;13/54(4):409–414.

Ferrara A., Raimondi S., d'Episcopo L., Guida L., Russo A., Marotta T. Olive Oil and Reduced Need for Antihypertensive Medications. Archives of Internal Medicine, 2000;160:837-842.

Garcia-Segovia P, Sanchez-Villegas A, Doreste J. Olive oil consumption and risk of breast cancer in the Canary Islands: A population-based case-controlled study. Public Health Nutrition, 2006;9(1A):163-167.

Galeone C., Talamini R., Levi F., Pelucchi C., Negri E., Giacosa A., Montella M., Franceschi S., Vecchia C. Fried foods, olive oil and colorectal cancer. Annals of Oncology, 2007;18(1):36-39.

Jakobsen M., O’Reilly E., Heitmann B., Pereira M., Balter K., Fraser G., Goldbourt U., Hallmans G., Knekt P., Liu S., Pietinen P., Spiegelman D., Stevens J., Virtamo J., Willett W, Ascherio A. Major types of dietary fat and risk of coronary heart disease: a pooled analysis of 11 cohort studies. American Journal of Clinical Nutrution, 2009;89:1425–1432.

Kalmijn S., Launer L., Ott A., Witteman J., Hofman A., Breteler M. Dietarv Fat Intake and the Risk of Incident Dementia in the Rotterdam Study. Annals of Neurology, 1997;42:776-782.

Kontogianni M., Panagiotakos D., Chrysohoou C., Pitsavos C., Zampelas A., Stefanadis C. The impact of olive oil consumption pattern on the risk of acute coronary syndromes: The CARDIO2000 case-control study. Clinical Cardiology, 2007;30 (3):125-129.

Kris-Etherton P. Monounsaturated Fatty Acids and Risk of Cardiovascular Disease. Circulation, 1999;100:1253-1258.

Linos A., Kaklamanis E., Kontomerkos A., Koumantaki Y., Gazi S., Vaiopoulos G., Tsokos G. Kaklamanis P. The effect of olive oil and fish consumption on rheumatoid arthritis - a case control study. Scandinavian Journal of Rheumatology, 1991;20(6):419-426.

Mozaffarian D, Katan MB, Ascherio A, Stampfer MJ, Willett WC. Trans fatty acids and cardiovascular disease. New England Journal of Medicine, 2006;354:1601-1613.

Perez-Jimenez F. International conference on the healthy effect of virgin olive oil. European Journal of Clinical Investigation, 2005;35(7):421-424.

Reiner Z., Catapano A., De Backer G., Graham I., Taskinen M., Wiklund O., Agewall S., Alegria E., Chapman J., Durrington P., Erdine S., Halcox L., Hobbs R., Kjekshus J., Filardi P., Riccardi G., Storey R., Wood D. The Task Force for the management of dyslipidaemias of the European Society of Cardiology (ESC) and the European Atherosclerosis Society (EAS). European Heart Journal, 2011;32:1769–1818.

Zatonski W., Willett W. Changes in dietary fat and declining coronary heart disease in Poland: population based study. British Medical Journal, 2005;331;187-188.

Zatonski W., McMichael A., Powles J. Ecological study of reasons for sharp decline in mortality from ischaemic heart disease in Poland since 1991. British Medical Journal, 1998;316;1047-1051.

Żbikowska A. Formation and properties of trans fatty acids – a review. Polish Journal of Food and Nutrition Science, 2010;60(2):107-114.

Xu J. Eilat-Adar S., Loria C., Goldbourt U., Howard B, Fabsitz R., Zephier E., Mattil C., Lee E.

Dietary fat intake and risk of coronary heart disease: the Strong Heart Study. American Journal of Clinical Nutrition, 2006;84:894 -902.

Roman Pawlak, Ph.D, RD is Associate Professor of Nutrition in the Department of Nutrition Science at East Carolina University.

Main image credit: Pexels.com. Additional images supplied by the author.

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This is a companion discussion topic for the original entry at http://spectrummagazine.org/node/8737
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this is so interesting and informative…i’ve appreciated the health articles we’ve been seeing lately…

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Timely for me and thank you very much, Roman. Just yesterday I was perusing articles on the web concerning food oils. I appreciate your greater in depth relation of health benefits, charts and nomenclature of the arterial composit.
Here is one that also lists which oils to avoid:
The ugly truth about vegetable oils (and why they should be avoided.

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Thanks for your kind comments. If you enjoyed these articles, you will enjoy the content of my website: www.drromanpawlak.com where you will find other articles, videos, etc.
As for the article, I wouldn’t recommend it. There are several problems with the content. I will give an example below. The author claims that virtually all refined oils are “bad” while butter is ok. The problem is, there is plenty of data to show that when items, such as butter, is replaced with vegetable oils, cholesterol levels are improved and cardiovascular disease rates drop. This effect is seen in small and large studies, and in population based data. For example, in Poland, under communism, the production of animal products was subsidized, thus, they were cheap and their intake, including butter, was rising in proportion to the raise in death due to cardiovascular disease. When communism was overturned, the subsidies stopped, the prices went up, while in the same time, inexpensive vegetable oils from western Europe were brought in. The rates of cardiovascular disease have been dropping ever since 1991. A similar impact has been seen in Finland, when saturated fat (butter contains mainly this type of fat) was largely replaced with refined, plant based oils. Have you also noticed a list of “Good fats to cook?” It includes the worst type of fat out there, when it comes to health effect. The first one listed is a coconut oil, animal fats follow. Big misconceptions (I have a serious of lectures on nutritional misconceptions and one of them has to do with coconut oil). Anyway, you get a picture, I hope.

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Olive oil is not only good for humans, it’s good for pets too. I put a little olive oil on my dogs food a couple times a week. Helps her digestion, and makes her fur smooth and glossy.

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It is unfortunate that this article doesn’t contain numbered references, but just a bibliography. Readers can’t readily determine which of the claims are supported by publications (and by which authors) and which are not.

Thus, for example, I can’t tell which vegan proponents of low oil consumption Pawlak is referring to. One prominent author and practitioner with that perspective (and once affiliated with St. Helena Hospital, though not an SDA), is Dr. John McDougall, MD. He is a strong advocate for minimizing use of free fats in one’s diet, and one of his co-lecturers often points out that olive oil contains high levels of saturated fats. McDougall notes that there is an association of obesity with those countries consuming high amounts of olive oil. I know from my own personal experience that during periods when I consumed high amounts of olive oil (any oil would have done this, but that was my oil of preference), I gained significant weight. McDougall, however, has discussed a number of published studies along these lines, not to mention his own clinical experience.

Here are a few links to McDougall’s comments on this (there are many more if you search his website), so you can form your own opinion:
https://www.drmcdougall.com/misc/2013other/news/oil.htm
https://www.drmcdougall.com/misc/2007nl/aug/oils.htm
https://www.drmcdougall.com/misc/2008nl/dec/fat.htm

Other vegan opponents to free oils including olive oil include Caldwell Esselstyn, Michael Greger and Michael Klaper. A quick online search will identify others. Many of these are doctors and other health practitioners speaking to a lay audience, but they based their conclusions on publications as well as clinical experience. I love olive oil! I suspect, however, that these guys are on the right track, and I have drastically curtailed my consumption. As McDougall wrote about studies supporting oil consumption, “The popularity of this message proves once again that ‘people love to hear good news about their bad habits.’”

I’m not sure about the independence of the Center of Excellence Foundation on olive oil and health, cited by Pawlak. From what I can see, it sounds like a center set up to support a regional agricultural economy based on olive oil. They may or may not publish objective research. However, it sounds about like the dairy or meat industry publishing studies on the benefits of milk and beef. Conclusions to be considered with a grain of salt…

In a different vein, I noticed the work of the above foundation, and several of Pawlak’s comments, pertain to trace nutrients (polyphenols and other allegedly beneficial phytochemicals). There is a place for that kind of work, but it must be balanced by wholistic studies. Trace chemicals may have beneficial effects, but the whole food may produce a different effect. Thus, we see numerous publications on the benefits of trace chemicals in chocolate, coffee, tea, various spices and herbs, etc., but that doesn’t mean these are all healthful foods, especially in quantity. This reductionist approach to science is great for cranking out publishable research papers and dissertations, but is of limited value for guiding dietary choices within a population. It is all too easy for an industry-sponsored research foundation to find a trace chemical in the sponsor’s food, whether it be milk, almonds, avocados, chocolate, coffee, you name it, and then publish papers on the benefits of that chemical, while giving scant notice to harmful effects of other components.

Finally, I am puzzled by the author’s discussion of smoke and burning temperatures; how is that relevant to his point that olive oil is safe to use for frying/cooking? I am not saying it is or isn’t; I’m just arguing that smoke temperature seems a totally inadequate basis for drawing any conclusions along those lines. If heated olive oil is unhealthful, the toxic or carcinogenic components should be looked for in the remaining oil. What smokes out of the pan is irrelevant low volatility components (whether naturally occurring or resulting from decomposition). Furthermore, the presence of smoke itself is not an adequate indication of the prevalence of an oil to decomposition, or whether that decomposition is purely thermal or is thermal-oxidative (accompanied by production of numerous oxygen-centered radicals and peroxidic species). Thermo-gravimetric analysis (TGA) is commonly used to measure loss of volatile species in heated compounds. There is not necessarily a correlation between the temperature for onset of weight loss (which smoking would cause) and the onset of chemical decomposition; it all depends on what the smoke is.

My little Chihuahua gets an extra portion of a special ground meat every evening with some extra virgin olive oil on it. No wonder she is so healthy… LOL

Thanks Dr. Pawlak for this article. So informative and a great help to keep our health in good shape. :+1::+1:

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Robert. I am referring to all of the individuals you mentioned. If you carefully review the references I included, you will find that, contrary to the views expressed by these individuals, my conclusions are based on the best available evidence as expressed by meta-analyses. No evidence from any individual studies or anyone’s clinical experience outweighs what we learn from meta-analysis. It is a pity to see, otherwise prominent health promoters, to promote views consistent with their personal bias over the best available evidence. As for your suggestion that olive oil may promote weight gain, anything if ingested in high quantities will do that. Having said that, nobody should be ingesting cups of olive oil. A couple to a few table spoons would likely what is needed. If you follow this recommendation along with eating an overall balance and healthy diet, coupled with regular physical activity, would make weight gain unlikely.

I have read the first link Robert included in his comment to one of the articles McDougall has written. Here is my reply:

McDougall: Common knowledge is using olive oil (monounsaturated fat) and eating nuts (polyunsaturated fats) are protective against heart disease, but there is evidence that questions the real life benefits:
Roman: Actually, most nuts contain more mono than polyunsaturated fats, walnuts are the exceptions.
McDougall:* Serial angiograms of people’s heart arteries show that all three types of fat—saturated (animal) fat, monounsaturated (olive oil), and polyunsaturated (omega-3 and -6 oils)—were associated with significant increases in new atherosclerotic lesions over one year of study.3 Only by decreasing the entire fat intake, including poly- and monounsaturated-oils, did the lesions stop growing.
Roman: 1) This is not what the data in the cited manuscript showed. Here is a quote: “Each quartile of increased consumption of total fat and polyunsaturated fat was associated with a significant increase in risk of new lesions. Increased intake of lauric, oleic, and linoleic acids significantly increased risk.”
2) Olive oil is not the only dietary source of monounsaturated fats or oleic acid. In fact, among the 10 top sources of the oleic acid, items such as grain based deserts, burgers, cheese, chips, chicken, sausages, etc. are found. Olive oil is NOT among the top 10 sources.
3) The protective effect of virgin olive oil is mostly attributed to the phytochemical content of the oil and less so to the type of fat found in it.
McDougall: * Dietary polyunsaturated oils, both the omega-3 and omega-6 types, are incorporated into human atherosclerotic plaques; thereby promoting damage to the arteries and the progression of atherosclerosis.4
Roman: Atherosclerosis is a byproduct of repairing the endothelial damage. The only thing that this data is telling us is that these fats may be used in this process. This data does not tell us that these fats promote the onset of atherosclerosis.
McDougall: * A study in African green monkeys found when saturated fat was replaced with monounsaturated fat (olive oil), the olive oil provided no protection from atherosclerosis.5
Roman: Irrelevant. There are many studies in humans that have shown protective effect.
McDougall: * One of the most important clotting factors predicting the risk of a heart attack is an elevated factor VII. All five fats tested—rapeseed oil (canola), olive oil, sunflower oil, palm oil, and butter—showed similar increases in triglycerides and clotting factor VII.6
Roman: In the mountain of manuscripts that have been published on the impact of olive oil on atherosclerosis and cardiovascular disease, there are outliers that have shown the opposite effect. Anyone can pick any of these outliers and prove his/her bias. Here is an example of a study that have shown the opposite effect: https://www.ncbi.nlm.nih.gov/pubmed/10584041
McDougall: Most likely, the heart benefits of a Mediterranean diet are due to it being a nearly vegetarian diet. The Mediterranean diet is a good diet in spite of the olive oil and added nuts.7
Roman: This is an isolated opinion that is contrary to the opinion of the vast majority of researchers/scientists and, most importantly, contrary to the best available evidence from reliable studies, which, with few exceptions, point in one direction: extra virgin olive oil is cardioprotective.