A raft of research suggests that olive oil is associated with heart health and an array of other benefits. Olive oil is also a key component of the Mediterranean diet, which is ranked No. 1 on U.S. News’ list of best diets overall for 2023 for the sixth consecutive year.

There are several olive oils typically available on U.S. store shelves, including:

Extra-virgin and olive oil are both grades of olive oil, says Alexandra Kicenik Devarenne, an international olive oil consultant, judge, writer and educator based in Petaluma in Sonoma County, California. Extra-light tasting olive oil, she adds, is not a grade; rather, it is a marketing term. This oil, she notes, is milder and more neutral tasting than extra-virgin olive oil because it is a blend of predominantly refined olive oil with some virgin olive oil.

Healthiest Olive Oil

Deciphering the differences between various kinds of olive oil can seem complicated if you’re not a researcher or if you don’t work in the olive oil industry. However, deciding which type of olive oil is the healthiest isn’t complex, experts say. Extra-virgin olive oil is clearly the healthiest because it’s the one that’s the least processed, says Jack Bishop, chief creative officer of America’s Test Kitchen in Brookline, Massachusetts.

Extra-virgin olive oil, like all olive oil products, is extracted from olive pulp mechanically, without the use of chemical solvents, explains Joseph R. Profaci, New York City-based executive director of the North American Olive Oil Association. To qualify as extra virgin, however, the extraction must be produced without excessive heat, typically with a centrifugal press and no chemicals. This process is referred to as “cold pressing.”

The process of refining olive oil destroys most of the antioxidants in virgin olive oil, but the healthy fatty acid profile remains intact, Profaci explains. Extra-virgin olive oil, he adds, is never refined. Antioxidants are natural compounds that may shield your body from cellular damage associated with chronic diseases, such as cancer.

Olive Oil Grades

What is an olive oil grade? Grades indicate the type of product, Profaci says.

The higher the grade, the higher the quality, adds Devarenne, who is also director of Extra Virgin Alliance, an international group of producers dedicated to making high-quality extra-virgin olive oil. Extra-virgin olive oil, for instance, is considered to be the highest grade and the highest quality.

There’s no industry-wide standard for olive oil grades. However, the U.S. Department of Agriculture has voluntary standards for olive oil grades, and, Devarenne says, individual olive oil organizations list several grades of olive oil. The International Olive Council, for example, lists seven grades of olive oil fit for consumption.

“All this talk of standards can be confusing, but the important thing to know is that extra-virgin is the best tasting and healthiest choice,” Devarenne says.

Overall, at least 75% of the extra-virgin olive oil marketed in the U.S. is sold by companies that say they apply the IOC or USDA standards, Profaci notes. Four states, including New York and California, enforce their own olive oil regulations, he adds. However, there’s no federal governmental agency enforcing these standards.

In 2022, the North American Olive Oil Association, the American Olive Oil Producers Association and Deoleo, a multinational Spanish olive oil processing company, filed a petition with the U.S. Food and Drug Administration asking for the establishment of a national standard of identity for olive oil. In other words, they requested regulations to ensure the purity and quality of olive oils in the U.S. The federal government has yet to take any action on it, Profaci says.

Health Benefits of Extra-Virgin Olive Oil

Extra-virgin olive oil is the healthiest kind of olive oil because it contains natural chemical compounds known as phenols or polyphenols, says Mary M. Flynn, a research dietitian at Miriam Hospital and associate professor of medicine at Brown University in Providence, Rhode Island.

“The phenols found in extra-virgin olive oil have (also) been shown to improve an impressive range of disease risk factors,” Flynn adds.

When it comes to improving those risk factors, phenols found in extra-virgin olive oil can contribute to:

For example, in a study published in the journal Biomolecules in January 2021, researchers suggest that extra-virgin olive oil “lowers blood pressure and reduces the risk of developing hypertension” partly because of phenols. Similarly, the FDA determined that the oleic acid in edible oils – including olive oil – may lower the risk of coronary heart disease.

In addition, research published in December 2022 in the journal Nutrients suggests that consuming extra-virgin olive oil is associated with enhanced brain function in people with mild cognitive impairment. Researchers also concluded that extra-virgin olive oil consumption is associated with improved blood-barrier function. This is notable because abnormal blood-barrier permeability is associated with brain atrophy and dementia.

Mitigating Concerns About Olive Oil

Olive oil, like many oils, is a fat in liquid form. While fats are generally viewed as bad for your health, the kind of fat is what matters. Saturated fat and trans fat, for example, raise your blood cholesterol levels and are linked to cardiovascular disease, according to the American Heart Association. Monounsaturated fatty acids, however, may actually improve cholesterol levels, which can then decrease your risk of stroke and heart disease, the AHA notes. Olive oil is high in monounsaturated fat.

Moreover, consuming olive oil in moderation could help prolong your life, according to research published in January 2022 in the Journal of the American College of Cardiology. Researchers noted that higher consumption of olive oil was associated with lower risks of total cause and specific-cause mortality. They also determined that replacing butter, margarine, mayonnaise and dairy fat with olive oil was associated with a lower risk of mortality.

In recent years, some have also expressed concerns about olive oil’s smoke point and that heating olive oil to high temperatures could release harmful compounds, remove the oil’s healthy benefits and perhaps even pose health risks.

However, 2018 research published in Acta Scientific Nutritional Health suggests that extra-virgin olive oil is safe when cooked at high heat (just over 400 degrees Fahrenheit). Researchers also found it more chemically stable at higher temperatures than other common cooking oils.

Taking Advantage of Health Benefits

To maximize the health benefits of extra-virgin olive oil, experts recommend these strategies:

Buy directly, in stores or online, from the producer when possible

When you buy directly from the person who is making the oil – which will usually mean buying online if you’re outside the olive oil-producing areas of the U.S. – you have a greater assurance of attention to quality, Devarenne says. Many producers have a website that will tell you about their farm and products. Although some of the online sellers are just bottlers of other people’s oil, you can find online olive oil boutiques that carry a small range of high-quality imported and domestic extra-virgin olive oil straight from the producer. The gold standard is “estate production,” which denotes an extra-virgin olive oil grown and milled by the brand owner. However, a seal indicating “estate grown,” in which milling is done by a third party, is also good, Devarenne says.

Shop at specialty stores

Your chances of finding high-quality extra-virgin olive oil are best if you shop at a boutique store that takes food – and olive oil – seriously, Devarenne says. Ethnic markets and gourmet stores or well-curated grocery outlets can be good bets. Look for good turnover in the stock by checking best-before dates. Also, check for display conditions that protect the oil from fluorescents and sunlight, avoid exposing the oil to air and keep the ambient temperature cool (more on that below).

Look for a harvest or best-before date

Ideally, you can opt for the freshest olive oil by looking for a harvest date. Here are the times of year that olives are harvested in different parts of the world:

Harvest dates, however, may not be on the bottle, so best-before dates are important to look for, explains Selina C. Wang, department vice chair and associate professor of cooperative extension in small-scale fruit and vegetable processing in the Department of Food Science and Technology at the University of California, Davis.

Timing can be particularly important with consuming olive oil in its peak condition. “With enough time, all olive oils, even the highest-quality oils, will become rancid from oxidation,” Wang says. “The bright flavors and health benefits in olive oil will diminish with time.”

It’s best to finish a bottle of extra-virgin olive oil between six weeks and four months of purchasing it, depending on how many people are consuming it and the size of the bottle. “Don’t save it for special occasions,” Wang says. “The oil will never get fresher or better. The earlier you can use it, the better.”

Know the taste of fresh oil, and sample it before or just after you buy it

Extra-virgin olive oil is a minimally processed food and should taste of fresh olives, not cured ones, Devarenne says. (Traditional table olives are cured by fermentation, which is not a good thing in olive oil.) The fruity notes in olive oil can be green, with grassy, herbaceous or artichoke flavors, or ripe, with a nutty, buttery or banana taste.

In general, olive oils with higher phenol content will have a bitter and/or peppery taste as well, Devarenne adds.

If the store doesn’t allow you to taste the oil before you buy it, take it home and taste it right away, Profaci advises. If you don’t like it, take it back. Return policies may vary, but supermarkets will generally take such products back and not charge the customer, he says. “Just don’t use half the bottle before returning it,” he recommends.

Choose a product in a protective container that excludes light

Extra-virgin olive oil’s biggest enemy is oxidation, which is caused by light, heat and oxygen. Therefore, it’s best to purchase olive oil that’s in a container that can keep the product as fresh as possible, Profaci says.

If given the choice, consider that olive oil in a light-resistant (typically dark) container would be better protected from light, he notes. Keep in mind that not all olive oil containers are bottles. Some olive oil is sold in metal tins or a bag-in-box, the way some boxed wines are sold.

Store the oil in a cool and dark place

To protect olive oil from oxidation, store it in a cool and dark place, such as a kitchen cabinet, Wang says. It’s not necessary to refrigerate olive oil, but it’s best not to leave it out on the kitchen counter near the stove either.

Look for a seal denoting high quality

When you’re shopping, look for olive oil bottles that have a quality certification seal, such as the ones from the California Olive Oil Council or the North American Olive Oil Association, Profaci says. Such seals confirm the product meets the standards of those organizations. This means the manufacturer has had the organization issuing the seals test its oils for compliance, though it doesn’t mean every batch is examined.