Health Benefits
Olive oil is a key part of the Mediterranean diet and is believed to have health benefits, such as reducing the risk of heart disease. But how did southern European countries come to introduce it into their food and what are its health benefits?
Olive oil has been the basis of the Mediterranean diet for thousands of years. The ancient Greek poet Homer even referred to olive oil as "liquid gold", while Hippocrates called it the "great healer" and prescribed it for many medical conditions.
It has been found that people living in the Mediterranean live longer and suffer less from heart disease than the Nordics and Americans. One of the reasons lies in their diet: most of the oils and fats consumed in the Mediterranean are healthier unsaturated fats than saturated fats. This observation, made by the American physiologist Ancel Keys in the late 1950s, led to the formalisation of what we now call the Mediterranean diet, which characteristically includes a lot of olive oil.
One of the benefits of olive oil is that it is very low in saturated fats: up to 85% of the fats in olive oil are monounsaturated fats (mostly oleic acid or omega-9) or polyunsaturated fats such as omega-6 and omega-3, while only about 15% are saturated fats. It also contains vitamin E which strengthens the immune system and vitamin K which helps wound healing, as well as phenolic antioxidants which improve health in many ways. For example, the polyphenols in olive oil contribute to the protection of blood lipids from oxidative damage, a health claim recognised and approved by the European Food Safety Authority (EFSA).
Different processes affect the quality of olive oil, resulting in different "types": refined or unrefined. Extra virgin olive oil is unrefined and obtained directly from olives using only mechanical processes and is full of healthy antioxidants. Chemically processed olive oils are cheaper (such as "virgin olive oil", "olive pomace oil" or simply "olive oil") and tend to have a bland taste, a lighter colour and fewer antioxidants, which means they probably offer fewer health benefits compared to extra virgin olive oil. Refined olive oil is the lowest quality form of olive oil, with little aroma, flavour or colour; it cannot be sold to consumers directly, but can be sold if blended with virgin olive oils.
Olive oil provides a greater health benefit when consumed raw, as the polyphenols and antioxidants it contains begin to break down when cooked at high temperatures. When heated, free fatty acids can also break down and form harmful, carcinogenic chemicals such as aldehydes, but olive oil contains mainly monounsaturated fats that are quite resistant to heat, so it is still a good choice for cooking.
