By Daniel Dawson

Olive oil has long been considered the healthiest fat around. The Greek poet Homer called it “liquid gold,” while Hippocrates, widely considered the father of medicine, referred to it as “the great healer.”

However, not all olive oil is created equally. Most celebrated health benefits of olive oil belong to a single grade : extra virgin olive oil (EVOO).

Extra virgin olive oil is made solely by mechanical methods, without heat or powerful petrochemical solvents used to produce refined olive oil and nearly every other edible oil. As a result, extra virgin olive oil retains the compounds that endow its numerous health benefits.

Thousands of studies have been published linking extra virgin olive oil consumption with a wide range of benefits, from its well-known heart-healthy qualities to more obscure ones, such as increasing testosterone in men with insufficient levels.

But what is it that makes extra virgin olive oil better than the rest? And why exactly is Homer’s “liquid gold” good for you?

Monounsaturated fats promote heart health

For thousands of years, the people of the Mediterranean basin have consumed olive oil as the main source of dietary fat.

Anecdotal evidence suggested they lived longer and healthier lives than their animal-fat-consuming neighbors to the north and across the Atlantic.

In 1958, Ancel Keys, a physiologist at the University of Minnesota, postulated a correlation between people’s diets and the observed incidents of coronary heart disease.

Keys’ landmark Seven Countries Study was the first to suggest that not all dietary fats are created equal.

The study’s findings showed that Greeks had lower rates of heart disease despite their high-fat diet, with olive oil being the main source of fat.

Other countries with high-fat diets from meat had higher rates of heart disease, suggesting that the type of fat consumed made a difference. The findings propelled the Mediterranean diet to popularity and fame outside of the Mediterranean basin.

Olive oil is about 73 percent monounsaturated fat by volume. The other 25 percent is saturated fats (14 percent) and polyunsaturated fats (11 percent).

Monounsaturated fats are fat molecules with fewer hydrogen atoms bonded to their carbon chain and a curved double-carbon bond, which makes them liquid at room temperature.

All fats – from saturated and trans to monounsaturated and polyunsaturated – help the body absorb vitamins and minerals, build cell membranes and are essential for the mechanisms that cause blood clotting, muscle movement and inflammation.