Olive oil linked with lower risk of death from dementia in new study

New Delhi: About a teaspoon of olive oil a day is linked with lowering the risk of death due to dementia by roughly 30 per cent, particularly in women, according to a new research.

Replacing five grams a day intake of mayonnaise and margarine ('vanaspati') with olive oil in equal amounts was found to be associated with a 14 per cent and eight per cent lower risk of death due to dementia, respectively.

An international team of researchers, including those at Harvard University, US, observed over 92,000 adults in the US for 28 years to study the effects of olive oil intake on the risk of dementia-related death. Dementia refers to an impaired ability to remember, think and make decisions, and thus, impacts daily activities and quality of life.

"Consuming at least 7 grams per day of olive oil was associated with a 28 per cent lower risk of dementia-related death compared with never or rarely consuming olive oil," the authors wrote. They also found that the results held good regardless of diet quality.

"Beyond heart health, the findings extend the current dietary recommendations of choosing olive oil and other vegetable oils for cognitive-related health," the authors wrote in the study published in The Journal of the American Medical Association (JAMA) Network Open.

Regular intake of olive oil may lower death risk from dementia by improving heart health, the researchers said.

Previous studies have shown that compounds in olive oil, especially extra-virgin olive oil, may lower inflammation and oxidative stress. It also restores the functioning of blood-brain barrier, which is known to falter in dementia and, thus, allows for the crossing of molecules toxic to the brain, the authors explained.

Following diets, such as the Mediterranean, DASH, and MIND, all of which include a teaspoonful of olive oil intake, along with green leafy vegetables, legumes, nuts and fish, has been shown to improve brain structure and cognitive function, the researchers said.

This highlighted a "potentially specific role for olive oil," as the team found that the highest olive oil intake had the lowest dementia-related death risk.

The participants with APOE e4 gene, the most common genetic risk factor for developing Alzheimer's disease, were found to be about five to nine times likelier to die due to dementia. Alzheimer's disease is the most common form of dementia.

However, the results regarding olive oil intake held good even after accounting for this factor, the authors said.