Paging Dr. Frischer: Olive oil

I spend a lot of time discussing nutrition with my patients, and get questions about olive oil every day. Is it the best oil? Does it have downsides?

Not all olive oil is the same. It comes in three grades: refined, virgin, and extra virgin (EVOO), which refer to the degree to which it has been processed with heat and chemicals. The more processing, the longer its shelf life at the market and in our homes. However, processing does alter its flavor and nutritional value.

Extra virgin is the least processed and freshest olive oil. It is often made with a cold press or stone press, so no heat is used. Avoiding heat helps to preserve its antioxidants. EVOO contains more healthy fat (unsaturated) than unhealthy fat (saturated). This helps to lower bad cholesterol, raise good cholesterol, and reduce the risk of heart disease and stroke.

Olive oil is the main source of fat in the Mediterranean diet, and is likely a major reason for the Mediterranean diet’s positive impact on heart disease, diabetes risk, and weight control. Along with being high in antioxidants and heart-healthy fats, EVOO is associated with decreased inflammation and a lowered cancer risk.

(A review of the importance of antioxidants: Antioxidants fight free radicals which lead to oxidative stress. Oxidative stress has been shown to cause increased signs of aging and the development of chronic disease.)

Ample research supports the benefits of olive oil. In one 2022 study, over a 28-year period high olive oil consumption was associated with an 8% to 34% lower risk of death related to disease. Participants who consumed higher quantities of olive oil were 19% less likely to die of cardiovascular disease and 17% less likely to die of cancer than were those who consumed less. There are likely additional benefits to bone health, diabetes prevention, cancer prevention, and brain health. (These areas are being studied.)

Is there a benefit to drinking EVOO? It doesn’t sound appealing to me, since we can incorporate it in our diet by cooking with it, drizzling it on salads, adding it to cooked vegetables or pasta, or dipping bread into it.

The downsides of extra virgin olive oil? It is more expensive, is faster to smoke, and can become bitter when heating. So, regular olive oil is a better choice for cooking at higher temperatures. Do note that even rancid olive oil is not known to have significant negative side effects, other than altered taste. The high number of calories in extra virgin olive oil is not considered to be a major health risk, because it keeps us feeling full, reducing hunger and food cravings. Nonetheless, all oil contains 126 calories per tablespoon. If your goal is weight loss, it is important to choose the best oil, but still to limit oil overall. Remember that olive oil is only oil, and contains no protein, no carbohydrates, and no fiber. (A tablespoon of EVOO does contain 13% of the RDA for vitamin E, and 9% of the RDA for vitamin K.)

EVOO is one of many foods that will help our bodies stay well and fight disease. I suggest that it be the primary source of fat in the foods we consume. Many have found that following the Mediterranean diet is the easiest way to do this.