A team of researchers from the Harvard T.H. Chan School of Public Health has discovered evidence that consuming olive oil daily may reduce the likelihood of developing dementia.
The study, published in JAMA Network Open, analyzed decades of data and found that people who consumed at least a half-teaspoon (approximately 7 grams) of olive oil daily were significantly less likely to die from dementia-related causes.
The connection between olive oil and better health outcomes has been widely studied, particularly within the context of the Mediterranean diet.
This diet, known for emphasizing legumes, vegetables, nuts, fish, dairy, and olive oil, has been associated with a variety of health benefits, including improved heart health and reduced inflammation. The new study suggests that olive oil itself may be one of the key components driving these positive outcomes.
To investigate the relationship between olive oil and dementia, the researchers analyzed data from two large-scale health databases: the Nurses’ Health Study, which tracks more than 60,000 women, and the Health Professionals Follow-up Study, which includes data on over 31,000 men.
These databases include up to 30 years of historical information, including dietary habits and causes of death.
Among the 92,383 individuals in the study, 4,751 had died from dementia-related diseases.
When comparing dietary patterns, researchers found that those who consumed at least a half-teaspoon of olive oil daily were 28% less likely to die from dementia-related illnesses compared to those who did not. This significant reduction suggests that olive oil may play a protective role in brain health.
The study also highlighted an important aspect of the participants’ diets: many of those who consumed olive oil regularly used it as a replacement for other fats, such as butter, mayonnaise, and vegetable oils.
By substituting these less healthy fats, participants likely reduced their intake of harmful saturated fats and processed oils, which might have contributed to the lower risk of dementia.
The researchers believe that olive oil’s benefits may stem from its anti-inflammatory properties. Chronic inflammation is a known risk factor for many diseases, including dementia. Olive oil is rich in antioxidants and healthy fats, which may help reduce inflammation and protect brain cells from damage over time.
While the study’s findings suggest a strong link between olive oil consumption and a reduced risk of dementia, the researchers also emphasize that this does not prove causation.
Other factors, such as an overall healthy lifestyle or other dietary habits, may also play a role. However, replacing less healthy fats with olive oil is a simple dietary change that could potentially offer significant health benefits.
The research team also pointed out that a Mediterranean diet, which incorporates olive oil as a staple ingredient, remains one of the most well-researched and effective diets for promoting long-term health.
The diet’s emphasis on natural, unprocessed foods, combined with olive oil’s unique properties, may work together to reduce inflammation, support brain health, and lower the risk of developing dementia.
In conclusion, this study reinforces the growing body of evidence that olive oil is not only a heart-healthy fat but also a valuable addition to a diet aimed at protecting cognitive health.
Regularly incorporating olive oil into meals—whether in cooking, salads, or dressings—may be an easy and effective way to promote overall well-being and reduce the risk of dementia.
If you care about Alzheimer’s, please read studies about the likely cause of Alzheimer’s disease and new non-drug treatment that could help prevent Alzheimer’s.
For more information about brain health, please see recent studies about diet that may help prevent Alzheimer’s, and results showing some dementia cases could be prevented by changing these 12 things.
The research findings can be found in JAMA Network Open.
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