In the news: Olive Oil May Help Protect Against Death From Dementia

Olive Oil Intake Lowers Risk of Dying From Dementia

Olive oil, an important component of the Mediterranean Diet, has been linked to various health benefits. Its ability to help lower LDL cholesterol along with the protective antioxidant and anti-inflammatory compounds it contains, may be why it’s associated with a lower risk of chronic diseases such as cancer and heart disease.

Results of a newly published study(1) from Harvard suggests that olive oil intake might also play a protective role for the brain.

To learn more about olive oil’s possible association with dementia mortality, the researchers analyzed the diets and health outomes of over 92,000 men and women who previously participated in two large studies: the Nurses’ Health Study II and the Health Professionals Follow-Up Study.

Participants in those studies reported on their food intake, including olive oil, every 4 years for 28 years

For the analysis, olive oil intake was categorized as never consuming the oil or less than once per month, consuming about 4.5 grams (1 teaspoon) daily, consuming 4.6 to 7 gram per day, or more than 7 grams daily.

The researchers found that consuming at least 7 grams of olive daily – slightly less than a half tablespoon – was linked to a 28% lower risk of dementia related death compared to participants who never or rarely use olive oil.

While the association held true for both men and women, it was particularly strong in women. Understanding why there might potential sex differences on how oil impacts brain health will require more research.

The protective effect of olive oil was also seen regardless of whether particpants had a genetic predisposition (homozygous for apolipoprotein E4) for one kind of dementia, Alzheimer’s.

Interestingly, the effect was seen regardless of diet quality, which was measured by how well participants stuck to the Mediterranean diet or the Alterntive Healthy Eating Index.

This finding implies that olive oil may be doing something to help safeguard against dementia mortality that augments or goes beyond the benefit of having a healthy diet alone.

The invesigators also reported that switching out 5 grams of margarine or mayo with an equivalent amount of olive oil lowered the risk of dementia mortality by 8-14%. Replacing olive oil for butter or other vegetable oils did not lower risk.

This analysis was comprehensive, taking into account lifestyle and sociodemographic factors (e.g age, ethnicity, income, etc) that can nfluence health outcomes. According to the researchers, that allowed them to isolate as much as possible the effect that olive oil use may have on dementia-related death.

Dietary Factors Influence Dementia Risk

Including olive oil on a daily basis may be part of a good strategy to stave off dementia, especially as part of Mediterranean diet. Keep in mind that research suggests that other factors such as eating healthy whole foods may influence dementia risk as well.

A recent study(2), for example, found that people eating the most ultraprocessed foods have a 28% faster decline in cognitive scores, including memory, verbal fluency, and the ability to plan and execute goals. Ultraprocessed foods are those with a lof additives like fats, sugars, artificial flavors and stabilizers, and which have undergone multiple processing methods.

References

1. Tessier A-J, et al. Consumption of olive oil and diet quality and risk of dementia-related death. JAMA Open. 7(5):e2410021, 2024.
2. Goncalves NG, et al. Association between consumption of ultraprocessed foods and cognitive decline. JAMA Neurol. 80(2):142–150, 2023.