Olive Oil May Reduce Risk of Fatal Dementia
If you read anything about optimal nutrition or dementia, you probably already know that olive oil has been linked to plenty of benefits for the brain. But a new study has shown that participants who consumed half a tablespoon of olive oil daily had a 28% reduced risk of dying from dementia compared to people who didn’t use olive oil. In addition, the researchers found that replacing just one teaspoon of margarine or mayonnaise with the equivalent amount of olive oil per day was associated with an 8-14% lower risk of dying from dementia.
These are hopeful findings, considering that the World Health Organization estimates that there are more than 55 million people in the world living with dementia with another 10 million new cases yearly. Factor in that dementia is the seventh leading cause of death among older adults and it’s easy to see why the study is so important.
For the study, which was the first to investigate the relationship between diet and dementia-related death, scientists analyzed dietary questionnaires and death records collected from more than 90,000 Americans over three decades. During that time, 4,749 of the study participants died from dementia.
Although previous studies have linked higher olive oil intake with a lower risk of heart disease and some protection against cognitive decline when used as part of a Mediterranean dietary pattern, the relationship between olive oil and dementia mortality risk in this study was independent of overall diet quality. What could that mean? It may suggest that olive oil had properties that are uniquely beneficial for brain health.
“Some antioxidant compounds in olive oil can cross the blood-brain barrier, potentially having a direct effect on the brain,” explains lead author Anne-Julie Tessier, RD, PhD, and postdoctoral fellow at the Harvard T.H. Chan School of Public Health. “It is also possible that olive oil has an indirect effect on brain health by benefiting cardiovascular health.”
Limitations of the Study
To be clear, this observational research doesn’t prove that olive oil is the cause of the reduced risk of dementia. More studies—including randomized controlled trials—would need to be done to confirm the effects and determine the optimal quantity of olive oil need to reap these benefits. But overall, it’s probably a smart bet to assume that replacing your margarine or mayonnaise with olive oil will help support a healthy diet.
“Olive oil may play a beneficial role in cognitive health through its rich content in monounsaturated fatty acids, which may promote neurogenesis,” speculated Dr. Tessier. “It also contains vitamin E and polyphenols that have antioxidant activity.”
So, just how much olive oil should you consume in a day in hopes of capitalizing on the benefits?
1. Studies vary anywhere from 1 to 5 tablespoons per day but aim for 3 tablespoons as a general guideline.
2. Look for “extra virgin olive oil” on the label, which indicates that the contents were prepared with a cold press to retain the most nutrients from the olive.
3. Consume the olive oil raw (on a salad or piece of bread) or cooked, as the high smoking point of olive oil makes it less likely to be heated enough to change its chemical composition.
4. Choose olive oils where only one country of origin is provided to ensure that all processes—from harvesting to pressing to bottling—occur in one place.
5. If a harvest day is provided, look for an early or first harvest, which indicates that the olives were pressed before ripening. These early and first harvests tend to produce the best tasting and highest nutritional quality options.
Wendy Burt-Thomas writes about the brain, mental health and parenting.
Check out the press release: