If you’re looking for ways for you or your parents to stay mentally sharp and reduce the chances of cognitive decline, then a recently published study in the journal Neurology should get your attention.
That’s because researchers found that consuming more flavonols—a compound found in fruits, vegetables, and tea—was associated with a slower rate of cognitive decline among a group of older adults.
The study focused on 961 dementia-free participants between the ages of 60 and 100 years old who were part of the Rush Memory and Aging Project, led by researchers at Rush University Medical Center in Chicago. The Rush Memory and Aging Project is a long-term study designed to measure mobility and memory in later life stages.
Researchers focused on flavonols, which are one type of flavonoid. Flavonoids are naturally occurring chemicals in plants that can help your health. Flavonols have been shown to reduce inflammation and provide antioxidants.
There are six major subcategories of flavonoids, including flavonols.
The diet consumed by the study participants was measured with a food frequency questionnaire. Researchers also used nearly 19 different standardized tests to assess cognitive performance and global cognition. The information they collected also measured flavonol intake.
Different types of memory were assessed, including:
- Episodic memory, or the long-term memory of previous experiences
- Semantic memory, which focuses on factual and conceptual information
- Visuospatial ability, which refers to the perception of spatial relationships
- Perceptual speed, or the ability to process visual information quickly
- Working memory, a type of memory used to hold on to information in the short term
The study also focused on four types of flavonols, including:
- Kaemferol
- Quercetin
- Myricetin
- Isorhamnetin
To better assess the study results, researchers adjusted for factors that are often associated with cognitive decline, such as:
- Age
- Education
- Participation in cognitively stimulating activities
- Physical activity
- Sex
- Smoking status
The Results – Do Flavonols Slow Cognitive Decline?
Overall, a higher intake of flavonols was linked to a reduced decline in global cognitive function.
Those who ate the largest amount of flavonols—equivalent to seven servings of dark leafy greens each week—had the slowest rate of cognitive decline.
In fact, the cognitive score of the frequent flavonol eaters went down 0.4 units more slowly per decade than those who ate the lowest amount of flavonols.
The effect was particularly notable with the flavonol kaempferol, found in dark leafy greens and in herbs such as dill and chives.
The other flavonol that appeared to have the greatest positive impact on memory was myricetin, which was associated with a 0.3 unit per decade slower decline than those who ate the lowest amount of flavonols. Myricetin is found in many fruits and vegetables, including dark-colored berries.
Quercetin was associated with a 0.2 unit per decade slower rate of decline. Foods and drinks with quercetin include berries, apples, citrus fruits, red wine, and tea.
No memory impact was found with the flavonol isorhamnetin.
Even after adjusting for other memory-affecting factors like age and education, the study results held up.
“It’s exciting that our study shows making specific diet choices may lead to a slower rate of cognitive decline,” study author Dr. Thomas Holland, an instructor in the department of internal medicine at Rush University Medical Center in Chicago, said in a prepared statement.
Study Limitations
Although the results are promising, researchers point out that the study has some limitations.
First, the study was done with a geographically similar group of older adults who were mostly white and well educated. This could make the results less applicable to other populations.
Another limitation is that the adults who had the lowest levels of cognitive decline may also practice other healthy habits that preserve their memory. They may also obtain benefits from eating a wide variety of vitamin and mineral-rich foods that contribute to better health and memory.
Studies such as this one are observational and do not show a direct cause and effect between eating flavonols and slowing cognitive decline.
Yet, even with these limitations, the results appear to support other similar studies that also found that flavonols and flavonoids contributed to better memory, according to Dr. Holland, the study co-author.
This is thought to be due to the flavonoids’ ability to:
- Lower brain inflammation
- Increase the brain’s ability to change with new experiences (also called brain plasticity)
- Lower oxidative stress, which can contribute to chronic diseases
It’s not yet clear if eating the fruits and vegetables (or drinking the wine or tea) rich in flavonols as a whole provide the most health and memory-boosting benefits compared with focusing just on flavonols themselves. In other words, the benefits may come from eating whole foods like fruits and vegetables versus focusing just on the flavonol components.
More research can help to clarify and confirm the current results.
Benefiting From Flavonoids
So, thinking of loading up on flavonoid-rich foods (both flavonols and other flavonoid components) now that you’ve learned about this study?
If the answer is yes, you may benefit both your memory and get antioxidant and anti-inflammatory benefits.
Here’s a primer on what you should be eating to get those flavonoid benefits:
- Apples
- Beans
- Berries and cherries
- Brussels sprouts
- Cauliflower
- Citrus fruits
- Dark, leafy greens such as kale
- Onions
- Peaches
- Raw spinach
- Red wine
- Sweet potatoes
- Tea
- Tomatoes
- Winter squash
It’s tricky to track flavonoid consumption because of the different types of flavonoids out there. The best approach is to consume a wide variety of fruits and vegetables, aiming for the recommended five servings a day of fruits and vegetables. Enjoy a wide range of these healthy foods and beverages for overall better health and a potential boost to your cognitive health.
Here are a few articles regarding healthy eating dependent on your age that can help you get started down the road to healthy aging.