A new study from Harvard University suggests that consuming just a spoonful of olive oil each day could significantly reduce the risk of dementia-related death. The findings, published in the Journal of the American Medical Association (JAMA) Open Network, add to the growing body of evidence supporting the powerful health benefits of this Mediterranean diet staple.
Researchers from the Harvard T.H. Chan School of Public Health, in collaboration with colleagues in China, analyzed data from two long-term studies on diet and health that began in 1990. The combined data from 92,000 participants, with an average age of 56 at the study's onset, revealed that those who consumed at least seven grams (about half a tablespoon) of olive oil per day were 28% less likely to die from dementia-related causes compared to those who never or rarely used olive oil.
"Olive oil may exert anti-inflammatory and neuroprotective effects due to its high content of monounsaturated fatty acids and other compounds with antioxidant properties such as vitamin E and polyphenols," lead author Anne-Julie Tessier, a nutritionist at Harvard University, explained to Healthline.
The protective effect of olive oil appeared to be particularly strong among women and remained consistent even if participants were more genetically prone to developing dementia. Interestingly, the researchers found that the association held regardless of overall diet quality. "Typically, people who use olive oil for cooking or as a dressing have a better overall diet quality, but interestingly, we found the association to be regardless of this factor," Tessier noted.
The study also revealed that replacing just five grams per day of margarine and mayonnaise with an equivalent amount of olive oil was associated with an 8% to 14% lower risk of dementia mortality. This finding highlights the potential benefits of making simple dietary substitutions to improve overall health.
While the study's results are promising, it is important to note that the participants were primarily White and educated, limiting the generalizability of the findings across diverse populations. Additionally, as an observational study, the researchers cannot directly link the outcomes to olive oil consumption alone.
However, this study is not the first to suggest a connection between olive oil and brain health. Previous research has indicated that people who regularly consume olive oil have about a 30% lower risk of dying from a neurodegenerative disease.
Domenico Praticò, a neuroscientist at Temple University who was not involved in the study, told Medical News Today in 2023 that there is "some evidence showing that it is the combination of all these different compounds more than a single element responsible for the positive effects."
As rates of dementia continue to rise globally, with no cure currently available, preventative measures through diet, physical activity, and mental exercises remain the best hope for mitigating these diseases, which already affect more than 55 million people worldwide.
The study's authors emphasize that the findings extend current dietary recommendations, suggesting that choosing olive oil and other vegetable oils may have cognitive-related health benefits beyond heart health.
While olive oil is a key component of the Mediterranean diet, which has been consistently associated with positive health outcomes, not everyone has equal access to this comprehensive dietary pattern. Understanding which specific elements of the Mediterranean diet have the most significant health impacts can help vulnerable populations improve their well-being through targeted dietary changes.
