Consuming a daily spoonful of olive oil may decrease the risk of death from dementia, as revealed by a recent Harvard study.
In an observation spanning 28 years involving over 92,000 adults, it was found that daily intake of at least 7 grams of olive oil (slightly more than half a tablespoon) reduced the risk of dementia-related death by 28% compared to those who seldom or never consumed it, according to research published recently in JAMA Network Open.
The study, peer-reviewed and presented in finalized form after initial findings were shared at the American Society for Nutrition’s annual meeting in July 2023, marks the first research to explore the link between this Mediterranean diet essential and reduced death risk from the disease.
Anne-Julie Tessier, a Harvard University research associate, emphasized the findings support dietary advice that promotes vegetable oils like olive oil for not just heart but potentially brain health as well. She advised opting for natural olive oil over fats like margarine and commercial mayonnaise to potentially lessen the risk of fatal dementia.
Participants, averaging 56 years at the outset, included nearly 60,600 women from the Nurses’ Health Study (1990-2018) and about 32,000 men from the Health Professionals’ Follow-Up Study. Every four years, their diets were assessed through questionnaires and the Alternative Healthy Eating Index, which predicts chronic disease risks based on dietary scores.
Substituting 5 grams of margarine or mayonnaise with olive oil daily correlated with an 8% to 14% reduced dementia death risk, whereas replacements with other vegetable oils or butter showed no significant impact. Even considering the APOE e4 gene—a significant genetic risk for Alzheimer’s—the olive oil benefit remained significant after adjustment for this factor.
However, experts like Duane Mellor stress that the association found does not imply causation, calling for further research to establish a definitive link.
The antioxidant properties of olive oil, capable of crossing the blood-brain barrier, along with its cardiovascular benefits, are suggested mechanisms by which it could enhance brain health. Lifestyle factors also play a role, with olive oil consumers generally leading healthier lives, though other confounding factors cannot be entirely excluded.
