Since the Mediterranean diet came on the scene, the recommended use of olive oil has been ubiquitous.
An analysis quoted (2014, Wikipedia) showed that elevated use of olive oil was associated with a reduced risk of all-cause mortality-cardiovascular events and stroke and type 2 diabetes. That olive oil use cut cancer death by 6% and that greater adherence to a Mediterranean diet is associated with a lower risk of Alzheimer’s disease, slower cognitive decline as well as Parkinson ’s disease.
One of the keenly cited benefits is the use of olive oil, which contains monounsaturated fats, most notably oleic acid. And the protection of olive oil is by way of the polyphenols against the oxidation of blood lipids.
[ii]Regular consumption of olive oil is associated with increased longevity and that the benefits include preventing cardiovascular risk factors including diabetes, metabolic syndrome and obesity as well as certain cancers including digestive and breast cancer. Though this article calls for more definitive research, this and another article says that olive oil is seen as being an:
Virgin olive oil is the one rich in phenolic compounds[iv] and is said that daily ingestion of this is beneficial and a key food for protection from cardiovascular issue. And it may be that extra virgin olive oil can be problematic as well because it is extremely perishable and can easily go rancid[v]. Perhaps semi-refined oil is better since when oil is exposed to light or air it oxidizes and the chlorophyll in extra virgin olive oil accelerates this oxidation. Spoiled oil will do more harm than good (Mercola) .
So keep your olive oil in a cool dark place and close the cap immediately--plus perhaps buy small amounts at a time or transfer to smaller containers to mitigate oxidation. Heating vegetable oil and cooking with olive oil is said to change it into an oxidant because at high temperatures, it burns. It is recommended to use coconut oil to cook with.[vi]
To tell if you have olive oil gone bad it:
- smells like crayons or putty
- tastes like rancid nuts and
- has a greasy mouthfeel.
Mercola indicates that corn, soy, safflower andcanola oil are highly damaged by heat and can clog arteries. He further warns as well about processed foods like potato chips, pre-made cookies and microwave dinners. They use of trans-fat which raises your LDL and is linked to heart disease.
Recently[vii] a review of 23 publications was done to see if heating vegetable oil increased the risk of chronic disease. The survey concluded that the myth of frying foods associated by the risk of cardiovascular disease is not supported by the evidence. That virgin olive oil significantly reduces the risk of cardiovascular clinical events and that high use of fried foods is related to higher risk of weight gain.
We recommend that you check with a nutritionist or do your own look up.