Older adults may lessen their chances of getting dementia by 15 percent by regularly eating citrus fruits like oranges, grapefruits, lemons, and lime, according to a study conducted by researchers from the Tohoku University. The Citrus consumption and incident dementia in elderly Japanese: the Ohsaki Cohort 2006 Study, which was published in the British Journal of Nutrition, explored the potential of citrus to positively affect cognitive function; in particular, it tackled the association between eating citrus and the onset of dementia.

• The cohort 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 answered 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 then 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 gotten dementia six years after the study.
• Using a multivariate-adjusted Cox model to measure the incidence of dementia, researchers found 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.

Journal Reference:

Zhang S, Tomata Y, Sugiyama K, Sugawara Y, Tsuji I. CITRUS CONSUMPTION AND INCIDENT DEMENTIA IN ELDERLY JAPANESE: THE OHSAKI COHORT 2006 STUDY. British Journal of Nutrition. 2017;117(8):1174–1180. DOI: https://doi.org/10.1017/S000711451700109X