High consumption of olive oil is associated with reduced dementia-related deaths

A new study suggests that high olive oil intake is associated with a significantly lower risk of dementia-related death, regardless of overall diet quality.

Data from a prospective study of more than 92,000 people showed that consuming at least 7g (about half a tablespoon) of olive oil per day was associated with a 28% lower risk of dementia-related death.

They found that replacing one teaspoon of margarine and mayonnaise with the same amount of olive oil reduced the risk of dementia-related death by 8% to 14%.

“Choosing olive oil, a natural product, instead of processed fats such as margarine and mayonnaise is a safe choice and may reduce the risk of fatal dementia,” said lead researcher Anjulie. – said Anne-Julie Tessier, MD, Research Scientist, PhD. in nutrition, Harvard University's TH Chan School of Public Health in Boston. Medscape Medical News.

However, she added, “intervention studies are needed to confirm causality and the optimal amount of olive oil intake.”

research has been published online on may 6th JAMA network open.

a spoonful of olive oil

There is a growing body of evidence linking the Mediterranean diet to health. Maintaining cognitive function Reduce risk cardiovascular disease (CVD). However, the association with dementia mortality was unclear.

Researchers studied more than 92,000 participants (66% female, mean age 56 (years old) was analyzed.

Both studies were conducted between 1990 and 2018 and used food frequency questionnaires to assess olive oil intake every four years. Dementia-related mortality was ascertained from death records.

The researchers also assessed the association between diet quality (particularly adherence to the Mediterranean diet and Alternative Healthy Eating Index scores) and olive oil intake with dementia-related mortality risk. They then estimated the difference in risk of dementia-related death when other dietary fats were replaced with the same amount of olive oil.

During the 28-year follow-up period, there were 4,751 dementia-related deaths. People with two copies of apolipoprotein ε4 (Apoe ε4) alleles — known risk factors Alzheimer's disease — Five to nine times more likely to have dementia-related death.

Compared with no or very little olive oil consumption, consuming 7 g or more of olive oil per day was associated with a 28% lower risk of dementia-related death (adjusted hazard ratio). [HR],0.72; P < .001), after adjusting for lifestyle and socio-economic factors. This result is Apoe ε4 Allele.

Each 5 g increase in olive oil intake was inversely associated with dementia-related mortality in women (HR, 0.88; 95% CI, 0.84-0.93) but not in men (HR, 0.96, 95). %CI, 0.88-1.04). .

No interaction by diet quality score was found.

unrelated to food quality

“People who typically use olive oil in cooking and dressings have better overall diets, but interestingly, the association between olive oil intake and lower risk of dementia-related death… “We found that this factor was unrelated,” Tessier said.

Researchers found that replacing 5g of margarine and mayonnaise per day with the same amount of olive oil reduced the risk of death from dementia by 8% to 14%. Other vegetable oil and butter substitutions were not significant.

“Some antioxidant compounds in olive oil can cross the blood-brain barrier and can have direct effects on the brain,” Tessier said. “Olive oil may also have indirect effects on brain health by benefiting cardiovascular health.”

The authors noted several limitations of the study, including the possibility of reverse causation due to the observational nature of the study.

It is also possible that higher olive oil intake is indicative of a healthier diet and higher socio-economic status, but the results remain consistent even after these factors are taken into account. the authors point out.

The study population included only medical professionals and was primarily non-Hispanic white, potentially limiting generalizability.

Causality and connection

Comment on the findings Medscape Medical NewsDr. Rebecca M. Edelmeyer, senior director of scientific engagement at the Alzheimer's Association, cautioned that the study was designed to show correlation, not causation.

Other notable limitations include measuring the prevalence or incidence of dementia from death records, as dementia and Alzheimer's disease are often underreported as causes of death.

Additionally, people in the highest olive oil consumption groups had better diets, consumed more alcohol, were more physically active and were less likely to smoke, Edelmayer said.

“All of these factors may influence the risk of cognitive decline and dementia, independent of or in addition to olive oil intake,” said the researchers involved in the study. No Edelmeyer said.

She echoed the authors' concerns that the study was conducted primarily on non-Hispanic whites and said that after adjusting for potential confounders, the protective effect of olive oil was not statistically significant for men. He pointed out that it was gone.

“It would be great if certain foods could slow or prevent Alzheimer's disease, but there is no scientific evidence that these claims are true,” Edelmeyer said. “Randomized controlled clinical trials are needed to assess whether foods have scientifically proven beneficial effects.”

This study was supported by a research grant to the senior author from the National Institutes of Health. NHS, NHSII, and HPFS are supported by grants from the National Institutes of Health. Tessier is supported by a Canadian Institutes of Health Research Postdoctoral Award. Senior author Guashferre is supported by a grant from the Novo Nordisk Foundation. Mr. Tessier reported no other relevant financial relationships. Disclosure information for other authors can be found in the original paper. Mr. Edelmeyer did not report any relevant financial relationships.

Batya Swift Yasgar (LSW, MA) is a freelance writer with a counseling practice in Teaneck, New Jersey. She is a regular contributor to numerous medical publications, including Medscape Medical News and her WebMD, and is the author of several consumer health books and publications. Behind the Burqa: Our Life in Afghanistan and How to Escape to Freedom (Memoirs of two brave Afghan sisters who told her their story).