Researchers from Tohoku University discovered that older adults who regularly eat citrus fruits have a lower likelihood of getting dementia, in a study published in the British Journal of Medical Nutrition. The paper, titled the Ohsaki Cohort 2006 Study, looked at how eating citrus can positively affect cognitive function. In particular, it studied how it can inhibit the onset of dementia, a condition that hits older adults – of which countries like Japan are prone, given their aging population.
The edible parts of citrus are filled with flavonoids. Other studies have been made to show that these flavonoids can permeate the brain-blood barrier and repair and reverse damage to the cells, thanks to its antioxidant and anti-inflammatory properties. A study noted that auraptene, a coumarin found in citrus, was able to suppress inflammation from brain ischemia, as evidenced by in vivo studies.
Likewise, other studies had also analyzed the link between citrus and dementia. A study conducted by researchers from the University of Nagoya and the University of Shizuoka identified nobiletin, a flavonoid found in citrus, to contain anti-dementia properties. Based on animal tests, nobiletin exhibited protective ability against memory deterioration caused by amyloid-? (A?), which is the main indicator for the onset of Alzheimer's disease. In addition, the flavonoid also possesses antioxidant properties, which also help deal with oxidative stress.
To further investigate, researchers analyzed data from the Ohsaki Cohort 2006 Study. The study was conducted in Ohsaki City in Japan on December 1, 2006. At the time, participants were either 65 years of age or older. Participants were then made to fill out a baseline survey to gather information regarding their frequency of citrus consumption. The survey contained questions pertaining to their diet, lifestyle, and their consumption of citrus. Based on their answers, the participants were grouped to those who eat citrus almost every day, those who eat at least three to four times a week, and those who eat at least two times or less per week. In 2012, the team followed up with 13,373 participants to note who had developed dementia six years after the study.
For the current study, researchers used a multivariate-adjusted Cox model to measure the incidence of dementia based on the cohort study. They found out that people who ate at least three to four times a week had reduced their risk of developing dementia by 18 percent, over those who rarely ate citrus. Moreover, people who ate citrus almost every day had lessened their chances by at least 23 percent.
With these results, the research team concluded that frequent consumption of citrus can lower the risk of developing dementia, stating that the discovery could be both a "simple and effective" solution in addressing dementia. (Related: Dementia and Alzheimer's disease overtake heart disease as the leading cause of death in America.)
Dementia, the condition wherein there is a significant cognitive decline, is a growing issue in Japan. It is estimated that 4.6 million people in the country have dementia, a real risk for the aging population of the country. The country's health ministry expects this figure to rise to 7.3 million (which is one out of five people aged 65 or older) by 2025.
Citrus isn't the only fruit that can help fend off dementia. Find more foods that help reduce your chances of getting this condition at Food.news.