Olive oil is an ancient food that has been used by people for thousands of years. It is the only oil that is extracted from a fruit rather than a seed, nut, or grain. Olive oil is mostly produced in Europe (Spain, Italy, France and Greece) and a small amount is produced in California and North Africa. Olive oil is sometimes called sweet oil.

Olive oil varies in color and flavoring depending on the ripeness of the olives, climate, type of soil and producers preferences. Color, which can vary from dark green to almost clear, depends on the refining process and is not a good indicator of flavor. A good quality olive oil will be thicker than refined products, but not too thick.

Olive oil contains no carbohydrates or protein. All of its' calories come from fat, mostly monounsaturated, making it an extremely heart healthy addition to your diet.

Nutrition Facts

The following nutrition information is provided by the USDA for one tablespoon (15g) of olive oil.

Calories: 119
Fat: 14g
Sodium: 0.3mg
Carbohydrates: 0g
Fiber: 0g
Sugars: 0g
Protein: 0g

One tablespoon of olive oil contains about 119 calories and 14 grams of fat, making it a high calorie food product. The good news is that the fat is healthy, mostly monounsaturated, around 6.7 grams and polyunsaturated, 4.6 grams. A small amount of calories come from saturated fat. But, although the fat is the healthy kind, you should still portion control your olive oil. Use it moderately in cooking and dressing food. And if you are using it in a single serving, note that one serving of fat is about one teaspoon of olive oil.

Health Benefits

Olive oil is rich in vitamin E, a fat soluble vitamin that supports normal nerve conduction and plays a role in immunity. It is also a good source of vitamin K, which is another fat soluble vitamin that is responsible for blood clotting.

In addition, olive oil is high in monounsaturated fat, which has been shown to increase good cholesterol (HDL) and lower bad cholesterol (LDL).

Some studies suggest that adding extra virgin olive oil to the diet, about one to two tablespoons per day, can have anti-inflammatory effects by reducing c-reactive protein.

Another way olive oil may help to protect the heart is based on its content of polyphenols. Some of the polyphenols in olive oil can prevent blood platelets from clumping together, which is a cause of heart attacks. The FDA supports the claim that "eating 2 tablespoons of olive oil each day may reduce the risk of coronary heart disease."

Other research suggests that consuming olive oil could protect us from cognitive decline, osteoporosis, and even improve the balance of bacteria in our guts.

It is important to note that many of the healthy components of olive oil, such as phytonutrients, are present in high amounts only in virgin and extra-virgin olive oil.

What Is Extra-Virgin Olive Oil?

The label designations virgin, extra-virgin, and pure olive oil refer to the level of acidity of the oil as well as the extent of processing used to extract the oil. General rule of thumb is the lower the acidity, the better.

Virgin olive oil is 100 percent unadulterated olive oil, meaning it is not heated or chemically processed. Instead, it is extracted from the olives purely by mechanical means (either by pressing or spinning the olives after they are mashed into a paste). The most superior "extra virgin" has the most nutrition, a lower acidify than virgin olive oil, very low rancidity, and strongest olive flavor.

Pure olive oil is processed from the pulp after the first pressing using heat and chemicals. It is lighter in flavor and less expensive. The benefit here is that it has a more neutral flavor and a higher smoke point. Virgin and extra virgin olive oil have lower smoke points and will start to break down when heated too high, yielding an off flavor.

Picking and Storing Olive Oil

The fats in olive oil make it susceptible to going rancid. Therefore, it is very important to protect it from light and heat. Once olive oil is opened, you should use it within six months. You know an oil is rancid when it smells or tastes off. To keep oil in the best condition aim to do the following:

Purchase olive oil in dark glass bottles. Certain hints of yellow and green block the damaging light rays that can cause an oil to go rancid.
Avoid purchasing bottles of oil that are dusty or have been sitting on the shelves for months.
Look to see if there is a date on the label, and try to get the freshest oil you can.
Store olive oil in a dark, cool place or the refrigerator until ready to use. When refrigerated, don't be alarmed if the oil appears cloudy and thick, it will become a liquid again once it is at room temperature.

If stored properly, olive oil with maintain its flavor and nutrition properties.

Healthy Ways to Use Olive Oil

Olive oil is a staple in Mediterranean and European cuisine. Use extra-virgin olive oil to drizzle vegetables, soups, stews, bean dishes, meats, fish, and poultry. Or, use it to make light saute or your own, lower sodium salad dressing.

If you are looking to cook at higher heats, such as grilling, you can use extra virgin olive oil. However, you are probably better off using vegetable oil, canola oil, virgin, or pure olive oil, due to their higher smoke points and more neutral flavor.

Heating extra virgin olive oil too hot can cause it to lose the properties that make it extra virgin. But it is important to note that some of the alternative oils are processed. Avoid extremely high heat cooking altogether, such as frying, as this type of cooking is rich in calories and may produce carcinogenic compounds.