July 6, 2020 | 55 minutes, 48 seconds
In This Article
Podcast Show Notes
Mary Flynn, PhD, RD, LDN is an Associate Professor of Medicine (Clinical) at Brown University where she teaches undergraduate course in nutrition and a research dietitian at The Miriam Hospital, where she has worked since 1984. She also lectures in the Warren Alpert Medical School on nutrition related topics. Her main research interest is how food can be used as medicine and her main food of interest is extra virgin olive oil, which she has been researching since 1998. In 2013, she founded The Olive Oil Health Initiative of The Miriam Hospital at Brown University that has a mission of educating the public and medical community on the health benefits of olive oil.
She is co-author of the books LOW-FAT LIES, high fat frauds and the healthiest diet in the world (Lifeline Press, 1999) and A Pink Ribbon Diet (Da Capo Press, October 2010) which is a weight loss program and cookbook for women who have had breast cancer based on her research of the plant based, olive oil diet that she has developed.
Olive Oil: The Heart’s Best Friend
Extra virgin olive oil is arguably the healthiest oil in the world. You would be hard pressed to find a study linking it to any health risks.
In fact, one study aimed to see if olive oil was safe for folks already having cardiovascular concerns. This study followed over 7,000 people ages 55 to 80 with high cardiovascular risk for almost five years. The results were astonishing!
Those who had the highest consumption of olive oil saw a 48% reduced risk of cardiovascular mortality. For each 10 gram increase in extra virgin olive oil consumption per day, cardiovascular disease and mortality risk decreased by 10% and 7%.1
Adding olive oil to your diet is great, but if you replace butter, margarine, and mayonnaise with extra virgin olive oil, you will see even more health benefits.
Olive Oil vs Coconut Oil
Even coconut oil, of which I am a fan, has issues. Unlike olive oil, studies on coconut oil show increased cardiovascular risk. (At the same time, many studies cite cardiovascular benefits.)4,5
Coconut oil and olive oil are grown in two very distinct climates: coconuts are tropical, whereas olives are Mediterranean. The indigenous diet, which supports the health benefits of coconut oil, is much different than the diet traditionally eaten in the Mediterranean. Foods that grew together may have been meant to be eaten together.
Wheat and olive oil, for example, are staples in the Mediterranean diet because both originated in Mediterranean countries. Wheat does not grow well in the tropics and was, therefore, not consumed with coconut oil.3 Traditional cultures figured out how to balance their macro and micronutrients from their traditional, time-tested wisdom and seasonally available foods. Many vegans, for example, do well with coconut oil because they have little saturated fat in their diet and have some of the lowest rates of heart disease of any diet.6
Introducing Olive Oil Researcher Dr. Mary Flynn
At Brown University, Mary Flynn, PhD has been researching the health benefits of extra virgin olive oil for decades. Her studies suggest consuming a minimum of two Tbs of extra virgin olive oil (EVOO) each day can improve your health. While her research was mostly done on just two Tbs per day, in my podcast with her, Dr. Flynn suggests that the benefits are even greater when we consume three Tbs of EVOO each day.
Dr. Flynn says, “Published studies show that no other food comes close to extra virgin olive oil for the prevention and treatment of chronic disease.”
In a meta-analysis of seven studies from 1998 to 2015, Flynn reports that extra virgin olive oil (EVOO), with a total phenol content of at least 161 mg/kg at a minimum intake of two Tbs (25 ml) a day, could significantly decrease systolic blood pressure in as little as three weeks. EVOO containing at least 300 mg/kg total phenols may also decrease diastolic blood pressure.
The study concluded that high-polyphenol content EVOO lowered blood pressure significantly more than polyunsaturated fats, refined olive oil, or canola oil. In each of these oils, polyphenols are removed during the refining process.
This study further reports that phenol-rich EVOO was more effective in lowering blood pressure than committing to a DASH (Dietary Approaches to Stop Hypertension) diet. The DASh diet recommends consumption of about nine serving of fruits and vegetables daily.10
Benefits of Two Tbs Extra Virgin Olive Oil Per Day8-11
- May lower blood sugar
- May lower inflammation
- May lower oxidation
- Can improve blood lipids (LDL, HDL)
- May help support weight loss
EVOO Helps Weight Loss
In another study published by Flynn, she followed 44 overweight women for six months and concluded that an olive oil-enriched diet brought about greater weight loss than a lower-fat diet. Moreover, these women overwhelmingly chose to continue the olive oil-enriched diet for six months during follow-up.11
Polyphenol Content Matters
Polyphenols are found not just in olives, but in many fruits, vegetables, nuts, seeds, roots, barks, leaves, herbs, whole grain products, and dark chocolate, as well as tea, coffee, and red wine.
Polyphenols are abundant in nature, with over 8,000 polyphenols identified and a couple of hundred in edible plants. However, polyphenols in olives are unique. Researchers like Flynn believe strongly that olive polyphenols are the key to the health benefits of olive oil.
Arguably, bioactive plant polyphenols are the primary cause of health benefits associated with olive oil. In olive oil, the content of polyphenols ranges from 50 to 1,000 mg/kg, depending on the soil, how they are grown (organic or conventional), ripeness at harvest, and extraction techniques, along with storage and packaging processes.7
Again, based on the range of polyphenols from one olive oil to another, it is critical to get the highest quality olive oil possible to ensure the greatest health benefits. Read on to see what olive oil won the LifeSpa olive oil test taste!
Bioactive Plant Polyphenol Benefits7
- Can reduce overall sickness/morbidity
- May slow development of cardiovascular and neurodegenerative disease
- Strong antioxidant against damaging reactive oxygen species
- Anti-atherogenic and anti-thrombotic
- Can boost immunity
The Olive Oil Diet
Professor Flynn suggests adding two to three Tbs EVOO each day, especially in combination with other healthy fats like nuts and seeds. She also recommends eating vegetables at each meal, with a particular Mediterranean emphasis on those with deep color and those from the cruciferous family. She also suggests consuming whole grains with minimal animal protein.
New Research on Cooking with Olive Oil
There has been much confusion around the safety of cooking with olive oil, as many studies find the smoke point of olive oil to be quite low. New research suggests that high-grade extra virgin olive oil is very stable at high heat and has a smoke point approaching 400°F.12
Past research may have suggested that olive oil should not be used for cooking, which is true when you use off-the-shelf grocery store-bought olive oil. This oil is likely not 100% pure extra virgin olive oil, as it says on the label. Research on these will result in an inaccurate conclusion with regards to whether olive oil can be used for cooking or not!
Most smoke point tests have been done on low-quality, adulterated olive oils purchased off a supermarket shelf. Studies on verified high-quality extra virgin olive oil have demonstrated low acidity, more stability, higher smoke point, higher resistance to oxidation, and longer shelf life.
See also Is Your Olive Oil Real?
The stable properties of high-quality EVOO are primarily due to the polyphenols. Refining the oil or taking lower-quality oil from later stages of pressing significantly reduces polyphenol content. In one study, certain store-bought olive oils had as much as five times the polyphenol content as others.13
In a 2015 study on cooking with extra virgin olive oil, researchers found that frying with olive oil and water not only preserved, but boosted antioxidant content of both the oil and the vegetables that were cooked.13,14
Olive Oil Taste Test
A few years ago at LifeSpa, my team and I organized an olive oil taste test using the best oils we could source from around the world, including France, Italy, California, and other countries. While there were amazing oils from Europe, the organic oils from California undoubtedly tasted the best. The winner of our taste test was from a small, family-owned farm in California named Fandango. Turns out we were not the only ones to taste test their olive oil: in the last nine years, they have won 95 olive oil competition medals. Check our all their awards here.
After investigating why their oil was so good, we found that just getting an organic certification in California is a major accomplishment, due to stringent toxin, heavy metal, and pesticide residue requirements laid out in the state’s Proposition 65.
At Fandango, on harvest day, olives are hand-picked when perfectly ripe, put into a certified organic mobile mill, then pressed immediately into oil. This process preserves the highest content of polyphenols and allows them to tout the lowest levels of oxidation on the market. Thank God for small farmers who care about small-batch quality, not quantity!
See also Dr. John’s Favorite Olive Oil
Over the years, the folks at Fandango have become good friends of ours, but LifeSpa has no business relationship with them other than that we love, trust, and highly recommend their award-winning olive oil.
How to Guarantee the Best Olive Oil
When sourcing olive oil, look for a harvest or press date. It is ideal to ingest the current year’s harvest.
If it is a California olive oil, make sure it is certified organic by California Certified Organic Farmers (CCOF) and certified extra virgin by the California Olive Oil Council (COOC).
If the oil is from Italy, look for a DOP seal (Protected Designation of Origin), which means the olives are from where they say they are.
Additional Resources on Olive Oil Health Benefits
- How Much Olive Oil (EVOO) a Day Keeps the Doctor Away?
- How to Choose the Best Olive Oil (Beyond Organic + Extra Virgin)
- The Scary Facts about Polyunsaturated Fats (Vegetable Oils)
- Olive Oil Removes Debris + Toxins from the Brain
- Cooking with Olive Oil: Know Your Fats
- Dr. John’s Favorite Olive Oil
- Canola Oil: A GMO Marvel
- Is Your Olive Oil Real?
- Don’t Use These Oils