- Olive oil is a staple of the popular Mediterranean diet.
- While past research has linked olive oil use to a decreased risk for several health concerns and conditions, the amount of olive oil a person should consume for the best health benefits is unknown.
- Researchers from the University of Florida found that following either a low or high-usage extra virgin olive oil (EVOO) diet resulted in lowered amounts of ‘bad’ cholesterol in the bloodstream.
- Scientists also discovered participants sticking to a low-use EVOO diet continued to see improvements in cardiometabolic markers during the 4-week carryover period.
Olive oil is a staple of the Mediterranean diet, which has become very popular over the last few years.
Previous studies have linked olive oil use to a decreased risk for several health concerns including
What hasn’t been clear up until now, say researchers from the University of Florida, is how much extra virgin olive oil (EVOO) in a diet is healthiest.
Through their new study recently published in the
However, researchers discovered in the 4-week carryover period, participants who followed a low-level EVOO diet continued to have significantly higher reductions in not only LDL-C levels, but also total cholesterol, high-density lipoprotein cholesterol (HDL-C),
For this study, researchers recruited 40 adults — 30 females and 10 males — between the ages of 18 to 79 years old who were at high risk for
Over 4 weeks, study participants were asked to follow a
“We know that plant based diets are better than the standard American diet,” Monica Aggarwal, MD, FACC, clinical associate professor, adjunct in the Division of Cardiovascular Medicine at the University of Florida and lead author of this study, told Medical News Today.
“We also have compelling data on the Mediterranean diet. What has not been clear [is] whether certain components of the diet are more or less beneficial,” she pointed out.
“One of the key differences between a Mediterranean diet and a whole food plant-based diet is the amount of fat and specifically olive oil in the diet,” Aggarwal continued. “I wanted to understand if the EVOO itself was good in a diet or just less bad than the alternative.”
At the end of the 4 weeks, researchers found study participants who followed either the high-use or low-use EVOO diets showed a significant reduction in blood LDL-C levels.
Additionally, both EVOO usage groups experienced similar reductions in
Aggarwal said they were not surprised by the study’s findings, as plant-based diets are associated with reduced LDL levels compared to a Western diet.
“LDL is the ‘bad’ cholesterol,” she explained. “It can build plaque in the blood vessels. Glycemic index is the blood sugars and are associated with diabetes. Inflammatory markers have been shown to be associated with increased event rates and reducing inflammatory markers is associated with reduced events.”
Additionally, Aggarwal and her team discovered that participants following the low-usage EVOO diet encountered even more reduction in LDL-C levels during the 4-week carryover period compared to those who followed the high-usage EVOO diet.
Higher reductions during the 4-week carryover period were also seen in total cholesterol, HDL-C, apolipoprotein B, and glucose levels in low-usage EVOO diet participants.
“This is the key finding,” Aggarwal said. “We found that with lower amounts of EVOO there were more significant reductions in LDL. That suggests that maybe EVOO itself is not the good part of a diet.”
“I would like to see a larger study looking at the same thing with larger washout periods to reduce carry over effects,” she added. “That is the next study that I would like to run.”
After reviewing this study, Jennifer Wong, MD, a board certified cardiologist and medical director of Non-Invasive Cardiology at MemorialCare Heart and Vascular Institute at Orange Coast Medical Center in Fountain Valley, CA, told MNT she felt the findings made sense that a diet lower in fat, even healthier monounsaturated fat like olive oil, lead to better metabolic profiles.
“Studies like these that look at both plant-based diet and the amount of oil — whether it’s monounsaturated healthy oils like olive oil or saturated fat — really help highlight the immediate metabolic effects that we see when people are randomized to healthier options,” Wong continued.
“I’d love to see the long term effects of these dietary changes not just in blood tests, but heart endpoints like heart attack, stroke, and death from cardiovascular causes,” she told us.
MNT also spoke with Monique Richard, MS, RDN, LDN, a registered dietitian nutritionist and owner of Nutrition-In-Sight, who agreed with this take.
“Initially I was not entirely surprised [by the findings] — the saying ‘more is not always better’ came to mind as a moderate amount of a good thing like EVOO is beneficial, more is not necessarily better. When participants had 4 tablespoons the benefits related to LDL levels were not as profound, and in fact adversely affected lipid levels related to cardiovascular risk compared to less than 1 teaspoon a day.”
– Monique Richard, MS, RDN, LDN
“Four tablespoons of olive oil equate to approximately 480 calories and 56 grams of fat — this is a significant portion of calories and fat in a 1500-2000 calorie diet from one source,” she explained.
“If the individual consumed any other whole plant-based foods such as nuts, seeds, avocado, coconut, etc., the lipid levels would be higher than recommended. Even though the fat sources would be derived from mono- and polyunsaturated sources versus saturated sources, too much of a good thing can become counterproductive and offset other nutrient levels and processes within the body,” said Richard.
She said it is also important to note that through the study’s dietary pattern methodology, adding 4 tablespoons of olive oil likely displaced other foods that may have been productive in lowering lipids, such as fiber-rich foods, protein-rich foods, or those lower in carbohydrates.
“Fat tends to be filling and takes longer to metabolize,” Richard added. “It may not have been solely the amount of EVOO but the other nutrient-dense foods that the higher amount of EVOO displaced.”
For those wondering how much EVOO is best for a healthy diet, Richard advised seeking out a registered dietitian nutritionist (RDN) or a credentialed nutrition expert to help calculate the type and amounts of fat a person should consume each day.
“In general, 450-540 calories from fat (50-60 grams per day) would be recommended for a 1500-1800 calorie diet daily, respectively,” she indicated.
“Keeping in mind that 1 tablespoon of EVOO provides approximately 120 calories and 14 grams of fat, it becomes apparent at how quickly recommended amounts can be reached or exceeded when factoring in other sources, lack of measuring when cooking or preparing recipes, or eating out where control of what was being added to the meal is out of your hands,” said Richard.
The nutritionist suggested readers ask themselves and family members questions like these to help garner more information on their overall intake of olive oil and fat intake in general:
- When cooking with olive oil am I measuring how much goes in the pan/recipe or meal or simply “eyeballing” what I think is the appropriate amount?
- Are there additional sources of olive oil I have overlooked included in the meal or day such as in salad dressings, condiments, hummus, breads, or sauces?
- What other sources of fats are consumed throughout the day — do I know what foods would be considered a fat?
“Unlike money these days, a little can go a long way with EVOO,” Richard continued. “Being meticulous with measuring amounts and calculating grams of fat is not necessary for most people, and in fact, is discouraged, as we don’t want to become obsessive or stifled with arbitrary rules and amounts.“
“However,“ she cautioned, “it is important to observe overall intake though and become aware of what may or may not be happening in your daily intake related to fat, fat sources, and quality.”