About Botanical Oils
The use of botanical oils can be traced back thousands of years, with roots in cultures as diverse as the ancient Sumerians, Chinese and Roman Empire. Botanical oils are prepared from whole plant, preserving its scent, main active ingredients, and the essence of the plant. Botanical oils made from various plants have been used throughout history to honor gods, prepare bodies for funerals, preserve beauty, assist with hygiene and treat a wide variety of medical conditions. Instructions for the preparation and use of plants as medicine is catalogued in the works of Dioscorides, De materia medica, back in the first century.
Modern technology has allowed the active parts of plants to be identified and studied for their role in health and their usefulness against various medical conditions. The value of botanical oils has stood the test of time.
The Properties Of Olive Oil
Of all botanical oils, olive oil is the most ubiquitous in the diet and health literature. Its medicinal uses began with Hippocrates, who used olive oil for skin conditions and as a base for ointments of all kinds. The olive tree holds a deeply revered place in history.
In Greek mythology, Zeus promised Attica to the god or goddess who brought the Greek people the more useful invention. Poseidon’s gift, alternately described as the horse or salt water, was rejected in favor of Athena’s gift of the olive tree. The city was renamed Athens and the olive tree assumed a place of prominence in the city’s food, medicine and material production. The award for winning the early Olympic competitions, which were held in Athens, was not a medal, but an olive branch twisted into a crown.
The olive tree and the oil of olives are mentioned throughout the Bible. In the story of Noah and the great flood, the dove returns to the Ark carrying an olive branch, and the oils used to anoint and heal individuals throughout the Bible are made from olives. It was Franciscan missionaries who brought the olive tree to California. The hearty olive groves survived where the Mission San Fernando fell to ruins. They remain largely in Northern California where the cost of land is lower and they are not run out by the more profitable grape crops or housing.
Types Of Olives
The olive, like the peach and almond, is a drupe – a fruit surrounding wrapped in a skin and containing a hard seed.
The popularity of the olive, whose botanical name is Olea Europa, has inspired hundreds of varietals. Various types are cross bred to accommodate growing season and climate as they are for most fruit, but olives inspire refinement as a delicacy, much as grapes are cultivated for wine varieties. Plants are selected by the polyphenol and aromatic compound content. These traits, along with the degree of maturity at which the olives are picked, are the main determinants of the oil’s flavor, stability and yield.
Olive oil is the backbone of the well-researched Mediterranean diet. All of its calories come from its beneficial fats, including omega 9s, omega 3 and primarily, omega 6s.
Monounsaturated fats are the most beneficial to health, and of the dietary oils, olive oil is the richest source. Specifically, olive oil has up to 77% monounsaturated oleic and palmitoleic fatty acids, 14% saturated palmitic and stearic acids and 9% polyunsaturated linoleic and linolenic fatty acids.
Linoleic acid, abundant in olive oil, is an omega-6 fatty acid. While omega-3 fatty acids, such as linolenic acid, are better known for their health benefits, the diet and health of skin and hair require a balance of omega-6 and omega-3 fatty acids. The American diet tends to contain a large amount of omega-6s, which can convert to the inflammatory arachidonic acid, especially when the source of them is meat. Plant sources of omega-6 fatty acids convert to gamma-linoleic acid, which is anti-inflammatory, before becoming arachidonic acid. The Mediterranean diet, which is well recognized as an effective means of combating heart disease, is rich in plant sources of omega-6s, including olive oil.
In addition to fatty acids, olive oil contains the fat-soluble nutrients vitamin E, mostly as the potent antioxidant alpha-tocopherol, and vitamin K. Several minerals are found in olive oil as well, including calcium, iron, potassium and sodium, all in fairly small amounts.
Not only does olive oil not contain any cholesterol it is a good source of plant sterols, which have been shown to decrease cholesterol. Better clinical studies are needed to determine whether the change in cholesterol that comes from consuming plant sterol-rich foods prevent deaths from heart disease, but it has been shown that a diet rich in phytosterols improves LDL, the type of cholesterol identified as a risk factor for heart disease.
Olive Oil Preparation
Olives have traditionally been collected by hand, which is the surest way to protect both the olive and the tree itself. Modern techniques that use sticks or machines to shake olives loose from the trees may be faster and more profitable, but they often bruise the fruit, compromising the flavor. Collection of olives can happen earlier in the season when the olive is transitioning from its green color to a purple hue, or later in the season, once the olive has turned purple, or at the very end of the season, when the olive has become fully black in color.
The olive fruit is very high in oleuropein, an intensely bitter compound, and much less sugary than fellow drupes. While oleuropurin is safe, it is utterly unpalatable. Olives must be cured before they can be eaten whole. This is accomplished by soaking or packing the olives in salt, salt water, water or lye. The curing process leeches the bitterness from the fruit and leaves a plump, firm fruit.
The abundant oil present in the olive is not from the seed, but the fruit itself. Only about 1% of the oil comes from the pit. To extract the oil, olives are washed, and then pressed under mechanical pressure into a paste. This breaks open the flesh of the fruit, releasing the oils. The paste is then stirred, or malaxed, to allow the small droplets of oil to form larger drops, and then spun to separate the oil. This separation used to be accomplished with presses, common in production of other oils, but very few olive oils are still collected this way.
Modern Oil Collection
Most modern processes for collecting olive oil use centrifuges. The first spin in the centrifuge removes the oil from the wet paste of malaxed olives. The second centrifugation is done at a higher speed and it removes water and other solids from the oil. The oil is then left to sit and allow gravity to remove remaining impurities. A final filtration step may be used in creating the finished oil. Oils that are filtered are usually filtered either through fine paper or diatomaceous earth. Filtration does remove more of the sediment that might accumulate in the bottle, but it also removes some beneficial phenolic compounds and shortens the oil’s shelf life.
Olive Oil Varieties
It is these nuances of preparation that create the varieties of olive oil on the shelf. Extra virgin olive oil, referred to as EVOO, is extracted via one cycle of cold pressing. True extra virgin olive oil will be labeled by the North American Olive Oil Association (NAOOA), an independent group that tests the quality of olive oils.
Virgin olive oil is also from a first pressing, but it has a higher acidity. An EVOO has about 1% acidity, but a virgin olive oil may have up to 2%.
Other blends may include Fino, which combines extra-virgin with some virgin oil, Light, which has been filtered to remove most potential sediment, and Pure, which is a combination favoring virgin mixed with some extra-virgin oils.
Medicinal Uses For Olive Oil
Olive oil is the only plant oil that can be used and consumed raw and untreated. Its use as a medicine was first noted by Hippocrates and is still vigorously explored in modern science.
Uses In Ayurvedic And Chinese Medicine
Olive oil is taken internally and applied topically. Being a Western herb, it does not have a long history of traditional use in Ayurvedic or traditional Chinese medicine. Olive oil can be used in Ayurvedic massage, where it is considered a warming oil that will encourage the dosha Kapha, a constitution that is oily, cool, heavy, slow and smooth. In traditional Chinese medicine, the olive is considered a neutral food, and may be used to heal sore throats, treat laryngitis or combat dysentery.
Olive oil is an important component of the Mediterranean diet, which is widely studied for its ability to reduce cardiac events and mortality from those cardiac events. Olive oil has been shown to reduce myocardial infarctions, strokes, high blood pressure and atrial fibrillation. It improves HDL – the “good cholesterol” – while decreasing LDL – the “bad cholesterol” – reducing the risk of atherosclerosis. Olive oil has been shown to reduce the risk of diabetes in elderly people who are at high risk for cardiovascular disease, and improve insulin sensitivity in middle aged people. It is also helpful for preventing metabolic syndrome and obesity.
While the Mediterranean diet itself, which is rich in fruits and vegetables, low in meat intake and high in whole grains, is beneficial for these conditions, it is specifically the supplementation with additional polyphenol-rich extra virgin olive oil that confers these benefits.
Olive oil has been used for constipation. A study showed olive oil to be an effective replacement for mineral oil in the treatment of constipation in patients undergoing hemodialysis. As interest and research into the microbiome and immune system of the GI tract expands, olive oil is being studied for its role in protecting the GI tract. It has been found to stimulate the local immune system of the gut  and support a beneficial shift towards healthy bacteria in the gut.
Olive oil, when used in high doses to augment the Mediterranean diet, has been shown to prevent breast cancer. This is probably due to its vitamin E and polyphenol content.
Olive oil is used to stimulate release of bile from the gall bladder in the popular protocol called the “Gall Bladder Flush.” This protocol is not recommended unless the presence of gall stones has been ruled out, as they may become lodged in the bile duct, causing a painful attack and risking the need for an emergency procedure.
Questions About Olive Oil
What should I look for in an olive oil?
Unrefined, extra virgin olive oil will contain the best profile of nutrients and fats. It may be darker in color and stronger in scent than a refined oil, but the overall scent and taste should still be fairly mild. There may be sediment that forms in the bottle.
If I am allergic to olives can I use olive oil?
Olive allergies are not common, but if you are allergic to olive, do not use olive oil topically or internally. Olive oil is made from whole olives.
Is it safe to give olive oil to kids?
Olive oil does not tend to be allergenic and can safely be added to children’s diet or used topically. If your child does have an allergy to olives, do not use olive oil with your child. Ask your doctor about testing for olive allergies.
Can I cook with olive oil?
Absolutely, and many people do. Extra virgin olive oils smoke at fairly low temperatures, so they are best used for cold dishes or recipes prepared with little heat. Virgin olive oil is good for lower temperature cooking, but is more stable against heat than an EVOO. The healthy phenols of olive oil break down under heat, so for health benefits they are best used in salad dressings or recipes that are not prepared with heat.
How long is the shelf life of olive oil?
Kept under proper storage conditions, olive oil will last up to two years. The high vitamin E content of olive oil actually works to protect it from the oxidative stress that forms as oil begins to go rancid, extending its shelf life. Olive oil should be kept in cool conditions, as it will break down at higher temperatures. It has been suggested that oils that solidify when left in the refrigerator are good quality. This test is really measuring the content of saturated fat in the oil, since all saturated fats will solidify as they cool. The amount of saturated fat is the result of the type of olive used, not the oil’s freshness.
Will I gain weight from the calories in olive oil?
Most studies show that weight loss is the result of more olive and olive oils in the diet. As a nutrient-dense food, it can help you feel full sooner, replacing higher carbohydrate foods that are lower in nutrients overall.
Caution And Considerations
Extra-virgin olive oil is frequently found to be fraudulently prepared. It may be adulterated with less expensive, more allergenic oils, such as soybean, corn or nut oils. If you have food allergies to any of these common additives, buy olive oil locally from a trusted source that can identify the grower and guarantee the purity.
 Bill T. Arnold, H. G. M. Williamson. Dictionary of the Old Testament: Historical Books. InterVarsity Press, Sep 26, 2011. P 33
 University of Maryland Medical Center.
 Rocha VZ, et al. “Effects of phytosterols on markers of inflammation: A systematic review and meta-analysis.” Atherosclerosis. 2016 May;248:76-83. doi: 10.1016/j.atherosclerosis.2016.01.035. Epub 2016 Jan 28. http://www.ncbi.nlm.nih.gov/pubmed/26987068
 AR Ness. Commentary: Is olive oil a key ingredient in the Mediterranean recipe for health? Int. J. Epidemiol. (2002) 31 (2): 481-482 doi:10.1093/ije/31.2.481
 Marta Guasch-Ferré, et al. Olive oil intake and risk of cardiovascular disease and mortality in the PREDIMED Study. BMC Medicine201412:78
DOI: 10.1186/1741-7015-12-78. http://bmcmedicine.biomedcentral.com/articles/10.1186/1741-7015-12-78
 M. Ruiz-Canela and M. A. Martínez-González, “Olive oil in the primary prevention of cardiovascular disease,” Maturitas, vol. 68, no. 3, pp. 245–250, 2011. http://www.maturitas.org/article/S0378-5122(10)00450-0/abstract
 Schwingshackl, Lukas, and Georg Hoffmann. “Monounsaturated Fatty Acids, Olive Oil and Health Status: A Systematic Review and Meta-Analysis of Cohort Studies.” Lipids in Health and Disease 13 (2014): 154. PMC. Web. 4 May 2016.
 Storniolo CE, et al. “A Mediterranean diet supplemented with extra virgin olive oil or nuts improves endothelial markers involved in blood pressure control in hypertensive women.” Eur J Nutr. 2015 Oct 8. [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/26450601
 Martínez-González MÁ, et al. “Extravirgin olive oil consumption reduces risk of atrial fibrillation: the PREDIMED (Prevención con Dieta Mediterránea) trial.” Circulation. 2014 Jul 1;130(1):18-26. doi: 10.1161/CIRCULATIONAHA.113.006921. Epub 2014 Apr 30. http://circ.ahajournals.org/content/130/1/18.long
 Fernández-Castillejo S, et al. Polyphenol rich olive oils improve lipoprotein particle atherogenic ratios and subclasses profile: a randomized, crossover, controlled trial. Mol Nutr Food Res. 2016 Mar 15. doi: 10.1002/mnfr.201501068. http://www.ncbi.nlm.nih.gov/pubmed/26992050
 Tresserra-Rimbau A, et al. “Intake of Total Polyphenols and Some Classes of Polyphenols Is Inversely Associated with Diabetes in Elderly People at High Cardiovascular Disease Risk
- Nutr. 2016 146: 4 767-777; first published online March 9, 2016.
 Buckland G, Gonzalez CA. “The role of olive oil in disease prevention: a focus on the recent epidemiological evidence from cohort studies and dietary intervention trials.” Br J Nutr. 2015 Apr;113 Suppl 2:S94-101. doi: 10.1017/S0007114514003936.
 Ramos CI, et al. “The short-term effects of olive oil and flaxseed oil for the treatment of constipation in hemodialysis patients.” J Ren Nutr. 2015 Jan;25(1):50-6. doi: 10.1053/j.jrn.2014.07.009. Epub 2014 Sep 17. http://www.ncbi.nlm.nih.gov/pubmed/25238699
 Martín-Peláez S, et al. “Influence of Phenol-Enriched Olive Oils on Human Intestinal Immune Function.” Nutrients. 2016 Apr 11;8(4). pii: E213. doi: 10.3390/nu8040213.
 Gutiérrez-Díaz I, et al. “Mediterranean diet and faecal microbiota: a transversal study.”Food Funct. 2016 May 3. http://www.ncbi.nlm.nih.gov/pubmed/27137178
 Potentas, Elżbieta, Anna Maria Witkowska, and Małgorzata Elżbieta Zujko. “Mediterranean Diet for Breast Cancer Prevention and Treatment in Postmenopausal Women.” Przegla̜d Menopauzalny = Menopause Review 14.4 (2015): 247–253. PMC. Web. 4 May 2016.
 Myriam Fezai, Laura Senovilla, Mohamed Jemaà, and Mossadok Ben-Attia, “Analgesic, Anti-Inflammatory and Anticancer Activities of Extra Virgin Olive Oil,” Journal of Lipids, vol. 2013, Article ID 129736, 7 pages, 2013. doi:10.1155/2013/129736
By Dr. Keri Layton, Naturopathic Medicine