Neurology, an antioxidant has been linked to slowing memory decline

According to a study published in the November 22, 2022 issue of the American Academy of Neurology, an online issue of the medical journal Neurology, people who eat or drink more foods containing antioxidant flavonols may experience slower memory decline, which is found in
several fruits and vegetables, as well as tea and wine.

"Excitingly, our study suggests that specific dietary choices may lead to a slower rate of cognitive decline," said
study author Thomas M.
Holland of Rush University Medical Center Chicago.
"Something as simple as eating more fruits and vegetables and drinking more tea are simple ways
people can play an active role in keeping their brains healthy.
"

Flavonols are a type of flavonoids, a group of phytochemicals found in plant pigments that have health benefits
.

The study involved 961 people
with an average age of 81 years without dementia.
They fill out a questionnaire each year about how often they eat certain foods
.
They also complete an annual cognitive and memory test, which involves recalling lists of words, memorizing numbers, and putting them in the correct order
.
They were also asked about other factors, such as their level of education, how much time they spend doing physical activity and how much time they spend doing intellectual activities such as reading and playing games
.
They were followed for an average of 7 years
.

Depending on the amount of flavonols in the diet, these people were divided into five groups
.
While the average intake of flavonols in U.
S.
adults is about 16 to 20 milligrams (mg) per day, the average dietary flavonol intake in the study population is about 10 mg
per day.
The lowest group consumed about 5 mg per day, and the highest group consumed an average of 15 mg per day; This is equivalent to a cup of dark leafy greens
.

To determine the rate of cognitive decline, the researchers used an overall cognitive score
that combined 19 cognitive tests.
The average score ranged from 0.
5 for people without thinking problems, to 0.
2 for people with mild cognitive impairment, to -0.
5 for people with Alzheimer's
.

After adjusting for other factors that may affect the rate of memory decline, such as age, sex and smoking, the researchers found that the cognitive scores of those with the highest flavonol intake declined 0.
4 per decade more slowly
than those with the lowest intake.
Holland notes that this may be due to the antioxidant and anti-inflammatory properties
inherent in flavonols.

The study also broke down flavonols into four components: kaempferin, quercetin, myricetin, and isorhamnetin
.
The foods that contribute the most to kaempferol are: kale, beans, tea, spinach and broccoli; Quercetin is found in tomatoes, kale, apples, and tea; myricetin is found in tea, kale, oranges and tomatoes; Isorhamnetin
is found in pears, olive oil, wine and tomato sauce.

The group with the highest intake of kaempferol declined at a rate of 0.
4 per decade slower than the group with the lowest intake of kaempferol
.
The group with the highest quercetin intake had a slower rate of cognitive decline by 0.
2 per
decade compared to the group with the lowest quercetin intake.
People with the highest intake of myricetin had a slower rate of cognitive decline by 0.
3 per 10 years compared to those with the lowest intake of
myricetin.
Isorhamnetin in the diet is not
related to overall cognitive performance.

Holland noted that the study showed a link between high levels of dietary flavonols and slower cognitive decline, but did not prove that flavonols directly lead to slower rates of cognitive decline
.

Another limitation of the study is that food frequency questionnaires, while effective, were self-reported, so people may not be able to remember exactly what
they ate.