A new study conducted by researchers based in Chicago has shown a possible link between a higher intake of antioxidant flavonols and a slower rate of memory decline.
Flavonols are a type of chemical found naturally in many fruits and vegetables, as well as plant products like wine, tea, and chocolate.
The study, which was published in Neurology, involved 961 people with an average age of 81 without dementia. The participants, who were followed for an average of seven years, completed questionnaires each year about their diet, as well as annual cognitive and memory tests.
They were also asked about other factors, such as their level of education, how much time they spent doing physical activities and how much time they spent doing mentally engaging activities such as reading and playing games.
Using this data, the researchers tried to find out whether a diet high in flavonols led to a slower decline in memory and thinking as the participants aged.
They found that the cognitive score of people who had the highest intake of flavonols through their diet declined at a rate of 0.4 units per decade more slowly than people whose had the lowest intake.
The study also broke the flavonol class down into the four constituents: kaempferol, quercetin, myricetin and isorhamnetin. They found that kaempferol and myricetin – commonly found in kale and tea – were more strongly linked to slower cognitive decline than other types of flavonol, at a 0.4 and 0.3 units per decade slower rate of decline, respectively.
“It’s exciting that our study shows making specific diet choices may lead to a slower rate of cognitive decline,” said study author Thomas Holland, Rush University Medical Center in Chicago. “Something as simple as eating more fruits and vegetables and drinking more tea is an easy way for people to take an active role in maintaining their brain health.”
Commenting on the study’s findings, Dr Sara Imarisio, head of strategic initiatives at Alzheimer’s Research UK, said: “While the researchers tried to establish how flavonols play a role in slowing cognitive decline, it is always difficult to rule out other factors that could influence the results of this type of research… What we can say for now is that there is a wealth of evidence which points towards eating a balanced diet as a way to reduce risk of cognitive decline.”