July 27, 2023 – If you could take a single pill that lowered your risk of heart disease, cancer, diabetes, neurological diseases like dementia and Parkinson’s, and early death in general, would you? Bad news: There’s no medication that can do all those things. But if you believe the headlines, one food can: Extra-virgin olive oil. It may be the ultimate superfood.
“There really is no other food that offers this range of benefits,” said Mary Flynn, PhD, an associate professor at Brown University who’s been researching olive oil for more than 20 years. “There’s no medicine.”
Just this week, new research out of Harvard University showed that people who eat more than half a tablespoon a day had a 28% lower risk of dying from dementia than folks who rarely eat it.
After decades of headline-making research, the olive oil bandwagon has plenty of passengers. On TikTok, videos about drinking daily shots of olive oil have received more than 1 billion views. Several companies now offer “medical-grade” olive oil that contains higher levels of beneficial compounds. Actors Brie Larson and Chloe Grace Moretz use it to clean their faces, and Jennifer Lopez credits olive oil, not Botox, for her age-defying glow. Earlier this year, Starbucks introduced a line of coffee drinks made with extra-virgin olive oil.
So how much is hype, and how much is backed up by research?
Olive Oil and Health: The Big Picture
For 6 decades, since the initial Seven Countries Study called attention to the Mediterranean Diet and its generous use of olive oil, researchers have been examining the health benefits of that golden fluid. And there are many.
A 2022 analysis of previous studies, covering hundreds of thousands of people, found that each additional 5 grams you eat daily – that’s a little over a teaspoon – can lower your risk of dying overall by 4%.
Extra-virgin olive oil is rich with polyphenols, a powerful group of antioxidants that fight inflammation.
“Inflammation is the base of any disease,” said Kristin Kirkpatrick, a registered dietitian nutritionist at the Cleveland Clinic. “So if we look at inflammation as the base, then we can see that olive oil can help with the reduction of a lot of different conditions.”
Researchers haven’t been able to pinpoint how, exactly, those polyphenols work, but they’ve consistently found similar effects across a wide variety of areas.
“As a scientist, I'm curious: What is the mechanism? How does this thing work?” said Tassos Kyriakides, PhD, an assistant professor at the Yale School of Public Health and one of the organizers of Yale’s annual Symposium on Olive Oil & Health. “But big picture, does it really matter if it's giving somebody a healthy outcome at the end? Does somebody who lives in a village in Sicily care about how this thing helps me be 95 and as sharp as ever?”
Olive Oil and Your Heart
The Seven Countries Study looked specifically at cardiovascular disease. Sixty-five years later, the notion that olive oil helps your heart is accepted as fact, because it’s high in heart-healthy monounsaturated fat and polyphenols. The European Food Safety Authority permits extra-virgin olive oils with enough of a certain polyphenol to make heart-related health claims on their labels.
“That’s a big, big statement, based on a lot of accumulated evidence,” Kyriakides says.
Kristin Koval, a 53-year-old writer from Boulder, CO, started eating olive oil daily 3 or 4 years ago. Her family has a history of heart problems related to genetically low HDL, the “good” cholesterol.
“There really isn’t a good drug to bring the level up, and I don’t love to take medicine if I don’t have to,” she said. “I read about some foods that help. I couldn’t eat salmon or sardines daily, but olive oil you can incorporate into your everyday life, so I did.”
Since she started, her HDL numbers have gone up. For the last 2 years, they’ve been in the normal range. “My doctor is happy, and so am I.”
Olive Oil and Your Brain
That new Harvard study on olive oil and dementia-related deaths builds on previous findings. Anne-Julie Tessier, PhD, a postdoctoral fellow at the Harvard T.H. Chan School of Public Health, presented the findings at the annual meeting of the American Society for Nutrition. She said they started the study because there’s so much evidence that the Mediterranean Diet helps with cognitive function, cognitive decline, and dementia risk.
“Olive oil is a significant proportion of the calories in the diet, so it made it very interesting to look at fatal dementia specifically,” she said. Replacing just one teaspoon of margarine or mayonnaise with the same amount of olive oil each day lowered the risk by 8%-14%.
Kyriakides, too, has researched olive oil’s effects on the brain. One small study produced promising results: Daily consumption significantly improved dementia symptoms in people with mild cognitive impairment.
Olive Oil and Cancer, Diabetes, and More
While olive oil’s effects on cardiovascular and brain health have received the most attention, researchers have found numerous other benefits:
- Cancer: An analysis of 45 studies found that people who consumed the most extra-virgin olive oil had a 31% lower cancer risk than those who consumed the least.
- Diabetes: Research has shown that eating extra-virgin olive oil can lower fasting blood sugars and insulin resistance. One study found that eating 25 grams a day (just under two tablespoons) lowers your risk of type 2 diabetes by 22%
- Pain relief: Oleocanthal, a polyphenol found in extra-virgin olive oil, has anti-inflammatory qualities similar to ibuprofen. Kyriakides considers himself living proof of this: Since he started using exclusively extra-virgin olive oil 9 years ago – yes, even for baking – he hasn’t taken a single ibuprofen or other common pain medicine, even after completing triathlons.
- Skin care: The research is less clear here – nobody’s proved that olive oil can clear acne, for instance – but those celebrities may be on to something. Olive oil’s phenolic compounds have higher antioxidant qualities than vitamin E, which has long been used in skin care, and its anti-inflammatory effects seem to help, too.
- Gut health: Researchers are just getting started here, but the results are promising. “The gut microbiome will see a lot of research activity going forward,” Kyriakides said. “Anything that has to do with the immune system, that’s where it’s processed. A healthy environment will give rise to a healthy system, which then affects everything else.”
How to Choose and Use Olive Oil for Your Health
To get these health benefits, you must use extra-virgin olive oil (EVOO). It comes from the first pressing of the fruit, made with no heat or chemical extractions – consider it the fresh-squeezed juice of the olive. Because it’s so fresh, it contains the highest levels of polyphenols.
There’s no universally agreed-upon dosage, but most clinical trials aim to replicate the amount in the average Mediterranean diet: two to four tablespoons a day. That adds up to quite a bit. In Greece, for example, the average person consumes two liters a month! Here in the U.S., we average a paltry one liter each per year.
“If we all had two tablespoons of extra-virgin olive oil a day, we’d be at a liter a month,” says Kyriakides. “That’s a magnitude of difference.”
And you may see some benefits take effect in as little as 3 weeks, according to Flynn.
Now that you know to look for EVOO, use these tips to choose one with plenty of those helpful polyphenols:
- You can absolutely buy polyphenol-rich olive oil at the supermarket. Expensive doesn’t necessarily mean best, but cheap almost certainly means you won’t get the benefits. “Think of the work involved in picking olives, producing the oil, bottling it, and sending it to be sold,” says Flynn. “With all that, a standard bottle of 500 ml can’t cost less than $10 for American oil, and from Europe more like $12-15.”
- For the highest-quality oil from the U.S., check the ingredients list. It should say “California olive oil.” That state set higher standards for EVOO than the U.S. Department of Agriculture and the International Olive Council, which covers Europe and the Mediterranean.
- One way to spot a high-quality bottle: It has a harvest date printed on the label. The fresher, the better.
- In addition to time, light and temperature can also degrade the quality of EVOO. Buy it in metal cans or dark bottles, and store it in a cool, dry place. If you must have some next to the stove, use a small jug and refill as necessary.
- Phenols have flavor! If you’d describe your olive oil as mild, it’s probably not EVOO.
- If the idea of taking a shot of olive oil the way they do in those TikTok videos makes you cringe, never fear. No studies have shown that taking it straight provides more benefits. In fact, some vegetables need to be cooked in oil in order to access their nutrients. Sauté or roast in EVOO, and you’re getting double the benefit.
Can you have too much EVOO? In terms of calories, perhaps – each tablespoon has 120 of them. But in terms of it harming your health in some way, the answer seems to be no.
“There are no ill effects from extra-virgin olive oil,” Flynn says. “In fact, more benefits can be found with more extra-virgin olive oil.”