Stay Sharp: Eat Your Flavonoids
Alzheimer's disease and other dementias can have devastating effects. Neuroscience is searching for ways to offset, delay, or prevent these maladies; after all, even brain scientists age. Now, a new study from scientists at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University may have hit on an easy way to keep your brain running at optimal health for longer.
Researchers looked at 2,800 people age 50 and older to study the long-term relationship between eating flavonoids (a family of natural substances found in plants) and the risk of Alzheimer's disease and related dementias, or ADRD for short. Studies have examined possible links between nutrition and dementia before, but the Tufts study sets itself apart by spanning 20 years. What did we learn?
Low intake of three different types of flavonoids was linked to higher risk of ADRD:
1. Flavonols. These are found in apples, pears, and tea (especially green tea and not herbal teas, which technically don't contain tea leaves). A low intake of this substance was associated with twice the risk of ADRD.
2. Anthocyanins. You can obtain anthocyanins through consuming blueberries, strawberries, and red wine. A low intake was associated with a four-fold risk of ADRD.
3. Flavonoid polymers. Like flavonols, these you can find in apples, pears, and tea (again, especially green tea and not herbal). A low intake was associated with twice the risk of ADRD.
If low intake is so risky, what is considered a high intake of flavonoids? The study found that the sixtieth percentile of intake amounted to a little less than two cups of blueberries a week (anthocyanins), 2 apples or pears a week (flavonols), and about 5 cups of tea a week (flavonoid polymers).
In a way, this is hopeful news. “When we look at the study results, we see that the people who may benefit the most from consuming more flavonoids are people at the lowest levels of intake," said first author Esra Shishtar, "and it doesn’t take much to improve levels. A cup of tea a day or some berries two or three times a week would be adequate."
Further data is needed. This study relied on people accurately reporting their daily food intake, which can be subject to forgetting errors, and the people questioned were predominately Caucasian. Still, in the meantime, upping your berry or tea intake certainly can't hurt.
“With no effective drugs currently available for the treatment of Alzheimer’s disease," said Paul Jacques, senior author, "preventing disease through a healthy diet is an important consideration.”