Olive Oil: The Great Healer

Olives, and olive oil, have been important foods for millennia. In fact, it was Hippocrates, the ancient Greek physician, who called olive oil “the great healer”.

The chemistry of olive oil is very similar to the oils of our skin, which may be why it has been used in beauty products for thousands of years. It contains vitamins E and K, and it is a mainly mono-unsaturated oil, so it doesn’t have negative effects on cholesterol. It is also rich in polyphenols*, those complex plant-based chemicals that are so good for your health.

The Mediterranean diet, considered by many to be one of the healthiest ways to eat, has olive oil at almost every meal. The American Heart Association has been recommending olive oil since 1961, with the first evidence-based data published in 1966. The health benefits of olive oil have continued to be validated by ongoing scientific research. More and more data is accumulating, showing that regular consumption of olive oil reduces all-cause mortality and is protective and beneficial in a wide range of health problems, including: 

• Cardiovascular disease

• Type 2 diabetes

• Fatty liver disease

• Anxiety and depression

• Breast cancer risk reduction

What does extra virgin olive oil mean? It is the first pressed oil of the olive, extracted without the use of heat or chemicals. Extra virgin first-pressed olive oil is like the pure juice of the olive fruit, providing the best quality, purity and nutrition, and it just tastes so much better!

After the first pressing, the remaining olive solids can then be further processed using heat and chemical extraction. This usually causes most of the vitamins and polyphenol content to be lost, as well as changing the flavour profile of the oil.

Buyer beware! 70% of commercial olive oil is “watered down” or adulterated with other less expensive oils. In fact, there is more “Italian olive oil” sold around the world than is made in the whole of Italy! However, in Chile, California, and Australia, it’s illegal to adulterate pure olive oil, so olive oil produced and bottled in those countries should be a pure product.

Many people have heard of the fridge test: the idea that pure olive oil solidifies in the fridge but adulterated olive oil does not. This is a myth. Adulterated oils can still solidify in the fridge. Peanut oil passes fridge test, as will olive oil cut with canola.

If in your travels you ever have a chance to sample high quality olive oil at the farm, check it out to taste the difference. It’s why simple dishes in Italy can taste so wonderful. Pasta olio aglio, a simple dish of olive oil, fresh garlic, fresh parsley and a few red pepper flakes, can be extraordinary when made with the best quality fresh olive oil.

Once any oil smells or tastes remotely rancid, throw it out. And don’t keep your precious olive oil on a sunny windowsill or right next to your hot oven, because it will be affected by heat and light. You’ve probably seen oils in a beautiful display with the sun shining through to show the lovely colour. Unfortunately, that sunlight is spoiling the quality of the oil, so always take a bottle from a darker shelf!

If you put butter on your veggies, switch up to using olive oil instead, or try our recipe for better butter:

Mix equal amounts of good quality olive oil with butter. Whip it up in a blender or Cuisinart, and store in the fridge. Your butter will go farther, and it spreads well straight from the fridge!

*Polyphenols Rich Food Chart

If you’d like to check out the research about olive oil and health, here are some references:

Nutrients.2025;17:570. doi.10.3390/nu17030570.

Mental Health--- Brit j Nutr.2024.doi.10.1017/S0007114524009299X.

Breast Cancer Risk Eur J Cancer.2025;24:115520. doi.10.1016.ejca.2025.115520

Olive Oil: Umbrella Review Nutr Rev.2025;83(3):e1311-1328. doi.10.1093/nutrit/nuae091.

Insulin Resistance and Seed Oils Front Nutr.2025.12:1532961.