What is Olive Oil and Extra Virgin Olive Oil?
Olive oil is pressed from olives and is most commonly mechanically extracted.
The solid parts of the plant material and its water content are separated from the mix to leave behind the oil.
"Refined", "unfiltered", "virgin", "extra-virgin" and many other terms are then used to describe how it has been produced and the alleged quality of the final product.
This includes whether, or not, the manufacturers used solvents in their process.
In the simplest terms, extra-virgin and virgin are terms used to sell an olive oil as healthier and less manufactured than other oils.
This said, it is well established that olive oils are highly fraudulent and that many products sold as olive oil, simply are not.
According to Forbes, "It's reliably reported that 80% of the Italian olive oil on the market is fraudulent." (1)
Are there Health Benefits to Extra Virgin Olive Oil?
Within the lesser adulterated oils, there are some beneficial plant compounds.
"An increase in consumption of virgin olive oil and other plant products rich in polyphenolic compounds [...] does seem to be rational and provide diverse health benefits." (2)
The above study finds polyphenols are associated with health benefits.
Extra Virgin Olive Oil contains higher concentrations of these polyphenols than other forms of the oil.
However, many plant-based food sources - including non processed, refined or oil-based sources - are rich in these polyphenols too.
"If you want nutritional value, you will find it by eating the whole olive—not by consuming it in its almost unrecognizable extracted oil form."(3)
If heart health is the goal then a whole olive with fibre, polyphenols, water, phytocompounds etc. is far more beneficial than an isolate or extraction which would see some of these reduced or even lost.
"All oils, both animal and plant derived, tend to worsen endothelial function. Within hours of ingesting fat, arteries stiffen and the ability to dilate is impaired."(3)
A further study (source 4) found it did not matter which oil was in question; olive, palm and soybean oil all caused a "detrimental effect" as refined oils.
It seems less the case that extra virgin olive oil is beneficial for health, and more that polyphenols are. In addition, plants rich in polyphenols can bring about these benefits without adding refined oils into our regular diet.
As a nutritionist, my recommendations are to be oil-free, or at the very least as close to that as possible.
Olive Oil and The Mediterranean Diet
According to the Harvard Health Blog the first point made in defining a Mediterranean diet is, "an abundance of plant foods, including fruits, vegetables, whole grains, nuts and legumes, which are minimally processed, seasonally fresh, and grown locally".(5)
Why so often, then, is the case made for this diet as a result of its lashings of olive oil?
There is "evidence of reductions in the risk for CVD (both heart disease and stroke) and lower risk of type 2 diabetes, lower blood pressure, lower LDL-cholesterol, as well as some cancers" associated with higher fibre intake.(6)
Conclusions: Is Olive Oil Healthy or Not Healthy?
When aiming for nutrient density, polyphenols, beneficial plant consituents and more specifically a way to reduce your risk of certain conditions a predominantly plant based to fully plant-based diet is a significantly better option than refined and processed oils.
Oils can change form when heated, they can often lead to altered CV health and while some may contain certain polyphenols they certainly do not replace whole plants as a food source.