I used to avoid oils because I thought all fat was bad for me. But really I was just confused about what fats my body needed and which ones I should limit or avoid. Our bodies need fat for a balanced and healthy metabolism – and not all fats are the same. Olive oil has been shown in studies to support cardiovascular health as well as have protective benefits for certain types of cancers.
Olive oil is a key ingredient of one of the healthiest diets on the planet – the Mediterranean style diet – and I am not just saying that because of my Sicilian heritage! Studies show that the Mediterranean diet without olive oil did not produce the same positive results, and that the consumption of olive oil was associated with reduced glucose, low-density lipoprotein cholesterol and oxidized low-density lipoprotein blood levels in comparison to a control group that did not use the Extra Virgin Olive Oil (EVOO) with the Mediterranean diet. 1
Let’s take a closer look at the golden-green liquid.
There are 3 levels of processing quality EVOO, VOO and LOO – with EVOO having the maximum physiochemical quality.
It just so happens that one of my closest friends is an olive oil sommelier and her parents own an olive farm in Tuscany. She describes the process on her parents biodynamic, environmentally friendly farm saying “It takes us only three or four hours to get the olives from the trees, into crates, and into the mill. It must be a fast process so we can avoid oxidation. Air, light, and heat are the enemies of the olive.” When an olive oil says that it is ‘Italian”, be careful because it could be blended with oils from other places – there are over 1.500 types of olives! Extra Virgin Olive Oil EVOO is the only unrefined oil that exists – and it should be made with no heat, just crushing the fruit.2
Going back as far as 7th century bc olive oil was examined for its nutritional and medicinal properties. Produced all over the world but predominantly in Mediterranean counties; Spain, Greece, Italy, Turkey and Morocco – oil from each of the different regions of each country has a distinct polyphenal profile. Polyphenols are reducing agents that work together with other reducing agents, such as vitamin C, vitamin E and carotenoids, to protect the body against oxidative stress and associated pathologies such as cancers, coronary heart disease and inflammation. 3
There are also nutritional variations in subtypes of olive oil from USA, Chili, Argentina and Australia. In general total polyphenol content is highest in extra virgin olive oil EVOO (approximating 55 mg/100 g as opposed to 21 mg/100 g in virgin olive oil.) 4
One Tbs of olive oil contains 119 Kcal, 13.5 grams of fat, 10 grams monounsaturated fat, 0 carbs , fibers and proteins, 1.9 mg vitamin E, and 8.1 ug vitamin K. 98% of olive oil is triacylglyerols – a high portion of this is mono unsaturated such as oleic acid. In a Mediterranean diet olive oil can make up 25% of total calorie intake.5
As far as using olive oil for cooking and heat stability at high temperatures, a study looking at smoking points of a variety of oils found that EVOO was shown to be the oil that produced the lowest level of polar compounds after being heated closely followed by coconut oil. “Extra virgin olive oil (EVOO) and other common cooking oils were heated up to 240o C and exposed to 180o C for 6 hours, with samples assessed at various times, testing smoke point, oxidative stability, free fatty acids, polar compounds, fatty acid profiles and UV coefficients. EVOO yielded low levels of polar compounds and oxidative by-products, in contrast to the high levels of by-products generated for oils such as canola oil.” This was attributed to EVOO’s fatty acid profile and natural antioxidant content which allowed the oil to remain stable when heated – unlike oils with high levels of poly-unsaturated fats which tend to degraded more readily.” 6 and other virgin oils such as avocado and high oleic acid seed oils.
Olive Oil Benefits
1. Olive oil is associated with the prevention of hypertension, obesity, diabetes, CVD, hypercholesterolemia, cancer and metabolic disorder.
2. Olive Oil contains phenolic compounds which show strong protective benefits in relation to breast, colon and thyroid cancers.
3. Olive Oil inhibits food borne pathogens and stimulates the growth of probiotics like L. acidophilus and B. bifidum. Bacterial effects will vary depending on the region the olive oil is from. Studies in vitro and animal studies do show some variance when it comes to the effect of olive oil on the microbiota – but observational studies on human population looking at blood lipid profile and hypercholesterolemia – showed olive oil reduced oxidized low density lipo-protein concentrations, increasing bifida bacteria, antioxidant phenolic compounds leading to lower LDL and cardiovascular protection. 7
4. A meta- analysis of daily consumption of olive oil, which included 3106 individuals from 30 RCT trials showed a decrease in C-reactive protein and inflammation. Comparing the medD against control diets and comparing olive oil against other fats, there was significant decrease in CRP. 8
5. In another a meta analysis looking at ten studies which included over a million subjects, it was concluded that protective effects were seen in CVD and stroke, endothelial function, inflammation, breast cancer and diabetes. Some question does remain as to the whether or not olive oil is the key benefit, or the overall health promoting lifestyle of the Mediterranean diet. 9 I would suggest that it is a combination, but that a high quality, EVOO plays a key role in its benefits and medicinal effects.
So drizzle that gold onto your salad, roast and sauté your veggies and favorite dishes with a few tosses of EVOO and enjoy your healthy lifestyle!
References: 1.6. Gavahian M, Khaneghah AM, et al. Health benefits of olive oil and its components: Impacts on gut microbiota antioxidant activities, and prevention of noncommunicable diseases. Trends in Food Science & Technology. 2019;88:220-227 2. Laura LaVelle. http://newswhistle.com/olive-oil-a-boutique-hotel-our-qa-with-rastrello-ambassador-lydia-bourne/. Updated June 17, 2019. Uploaded June 19, 2019. 3.Tapiero H, et al. Polyphenols: do they play a role in the prevention of human pathologies? Biomed Pharmacother. 2002;56(4):200-7. 4. 7. 9. Foscolou A, Critselis E, et al. Olive oil consumption and human health: A narrative review.Maturitas. 2018;118:60-66 5. De Alzaa F, Guillaume C, et al. ACTA Scientific Nutritional Health. Evaluation of Chemical and Physical Changes in Different Commercial Oils during Heating. 2018;2(6): 8. Schwingshackl L, Christoph M, et al. Effects of Olive Oil on Markers of Inflammation and Endothelial Function—A Systematic Review and Meta-Analysis. Nutrients 2015, 7(9), 7651-7675; https://doi.org/10.3390/nu7095356