A spoonful of olive oil a day reduced the risk of death from dementia by tens of percent
An international group of scientists conducted a study involving more than 92,000 people and showed that just seven grams of olive oil a day can reduce the risk of death from dementia by 28 percent.
Olive oil is a staple of the Mediterranean diet, which has been called one of the healthiest diets in the world (for example, it reduces the risk of cardiovascular disease). But olive oil is useful in itself: it contains a lot of monounsaturated fatty acids, especially oleic acid. It is believed that these acids reduce the level of "bad" cholesterol and maintain the level of "good" cholesterol. Admittedly, the exact mechanism of this has not been established.
Researchers from Harvard School of Public Health (USA), Zhejiang (China) and Copenhagen (Denmark) Universities conducted a prospective cohort study involving 92,383 people, 60,582 of whom were women. The mean age of the subjects was 56.4 years, and follow-up lasted for 28 years, from 1990 to 2018. None of the volunteers were initially diagnosed with cardiovascular disease or cancer. The findings of the paper are presented in the journal Jama Network Open.
During the entire study period, 4751 people died from dementia. It turned out that participants who were homozygous for the apolipoprotein APOE ε4 allele had a five to nine times higher risk of dying from neurodegenerative diseases than all others.
However, even with this adjustment, consuming at least seven grams (about a teaspoon) of olive oil per day reduced the likelihood of dying from dementia by 28 percent. Substituting other vegetable oils or butter had no such effect.
"Olive oil may have anti-inflammatory and neuroprotective effects due to its high content of monounsaturated fatty acids and other compounds with antioxidant properties, such as vitamin E and polyphenols," Anne-Julie Tessier of the Harvard School of Public Health said.
Perhaps the combination of such compounds, rather than a single element, allows for a similar health-promoting effect.
The scientists also emphasized that the study involved mostly white and educated people, so it is not yet correct to extend the results to other populations. Moreover, the study was observational (that is, the data were collected by simply observing naturally occurring events), so it is still premature to speak of a direct correlation between the reduction in the risk of death from dementia and the use of olive oil.