- Opting for olive oil could reduce your risk of fatal dementia, according to a new study.
- Participants who included half a tablespoon of olive oil in their daily diet were 28% less likely to die of dementia.
- The study authors found that replacing a single teaspoon of margarine or mayonnaise with olive oil reduced the risk of fatal dementia by 8–14%.
Researchers have observed an association between daily consumption of olive oil — instead of margarine or mayonnaise — and a reduced risk of dying from dementia.
According to the
The leading form of dementia is Alzheimer’s disease (AD), which affects an estimated 6.7 million people over the age of 65 in the United States.
According to a news release, the new study found that people who consumed half a tablespoon of olive oil daily had a 28% reduced risk of dying from dementia compared to people who did not use olive oil.
The study analyzed health records from 1990 to 2018 for 60,582 females and
Replacing just a single teaspoon of margarine or mayonnaise with olive oil was associated with an 8–14% reduced risk of dying from dementia, according to the study authors.
The study’s full results will be presented at the NUTRITION 2023 conference this week.
The established healthfulness of the Mediterranean diet provided the inspiration for the study, said study author Dr. Anne-Julie Tessier, a registered dietitian and nutrition research fellow at the Harvard T.H. Chan School of Public Health.
“Given that olive oil is the primary source of added fat in a typical Mediterranean diet, we were interested in examining its association with fatal dementia,” Dr. Tessier told Medical News Today.
In their research, Dr. Tessier and her colleagues found that the association of olive oil with a lower risk of death from dementia persisted regardless of diet quality, including how closely people adhered to the Mediterranean diet.
Dr. Tessier speculated on what it is about olive oil that results in its brain benefits:
“Olive oil may play a beneficial role in cognitive health through its rich content in monounsaturated fatty acids, which may promote neurogenesis. It also contains vitamin E and
polyphenols that have antioxidant activity.”
Dr. Domenico Praticò, director and professor at the Alzheimer’s Center at Temple University, who was not involved in the study, noted that “other compounds such as oleocanthal and oleuropein are [also] considered beneficial.”
“There is also some evidence showing that it is the combination of all these different compounds more than a single element responsible for the positive effects,” Dr. Praticò added.
Dr. Amal Khalil Kaddoumi, a professor at the Harrison College of Pharmacy at Auburn University who was not involved in the research, has studied the link between olive oil and Alzheimer’s biomarkers. Her 2022 study evaluated the effects of olive oil on dementia, but not fatal dementia.
Dr. Kaddoumi and her colleagues found olive oil could protect the brain, improve memory, and reduce Alzheimer’s biomarkers. They suggest that oleic acid found in olive oil may contribute to the effect.
“EVOO [extra-virgin olive oil] enhanced the blood-brain barrier function and functional connectivity between different brain areas in individuals with mild cognitive impairment (MCI), which could emphasize EVOO-phenolics’ effect,” Dr. Kaddoumi told MNT.
Refined olive oil, or ROO, increased the functional brain activation for memory tasks in brain regions involved in cognition.
The new study found olive oil more brain-protective than margarine and mayonnaise.
Dr. Tessier pointed out some difference in levels of fatal dementia in her study may have to do with the fact that “until recently, commercial mayonnaise and margarine could contain artificial trans fats.”
Most research — Dr. Kaddoumi’s being an exception — involves only EVOO, so there is more data regarding its benefits, said Kristin Kirkpatrick, a registered dietitian.
“In general, extra virgin olive oil, which is prepared with a cold mechanical press, is considered the best for health benefits,” Dr. Praticò said.
This processing method, noted Kirkpatrick, “will retain the most nutrients from the olive, and is critical to the ‘extra virgin’ standard.”
Kirkpatrick cautioned that some manufacturers surreptitiously mix EVOO with other oils to lower their costs, and has posted guidance for choosing the best-quality olive oil and the best methods for storing it.
When it comes to the healthiest way to consume EVOO, said Dr. Dr. Praticò, “it is common opinion that the best way to use it for a health benefit is raw (on your salad, on a piece of bread, etc.).”
However, cooking olive oil is also fine, since, said Dr. Kaddoumi, it has a high smoking point, making it less likely to be heated enough to change its chemical composition.
According to Dr. Praticò, a healthy daily serving of olive oil is two tablespoons daily.
Noting that studies vary anywhere from 1 to 5 tablespoons daily, Kirkpatrick said, “I advise my patients to aim for at least 3 tablespoons a day for brain health.”
When asked if a person could consume too much olive oil daily, Dr. Tessier said:
“We did not observe an amount at which there was no longer an association, although it is important to note that few individuals consumed above 15 g/day — that is 15,000 mg/day — of olive oil,” Dr. Tessier said.
“We found a clear linear dose-response association between higher daily olive oil intake and lower risk of fatal dementia,” Dr. Tessier concluded.
