Little memory slips are common as you get older. Forgetting why you went up the stairs shouldn’t necessarily be cause for concern. But at what point should you call a doctor? You’re not alone if you worry about developing something serious, like dementia or Alzheimer’s disease. Fortunately, you can reduce your risk by improving your diet. A study from the journal Nutrients found that one sweet treat in particular — strawberries — cuts down your risk of the disease by 34 percent.
It’s no secret that strawberries are packed with health benefits. They’re rich in vitamin C manganese, folate, plant compounds called flavonoids, and antioxidants (molecules that reduce inflammation and prevent cell damage). Previous research shows that a diet high in antioxidants may lower the risk of heart disease and other cancers. But why might the antioxidants in strawberries reduce the risk of Alzheimer’s?
Linking Strawberries to a Lower Chance of Alzheimer’s Disease
For the Nutrients study, researchers from the Rush University Medical Center in Chicago wanted to know why strawberries reduce Alzheimer’s risk. Previous studies already established that the fruit improves brain function. However, most of those studies were performed on animals, and the findings did not address Alzheimer’s disease.
As such, the research team investigated the issue with data from the Rush Memory and Aging Project. This ongoing project measures the decline of cognitive and motor functions in participants. To narrow things down, the team analyzed the data of 925 participants between 58 and 98 years old. About 75 percent of them were female. All the participants were dementia-free at the start, completed a food frequency questionnaire, and had a neurological evaluation once a year.
At each evaluation, the participants went through a three-stage process that determined whether they had Alzheimer’s disease. The researchers analyzed each of these evaluations and the food questionnaires. The food questionnaires helped them see how many strawberries every participant ate.
From there, the team examined the antioxidants and flavonoids each participant consumed based on their strawberry intake. All the volunteers had between zero and two servings of strawberries per week. The average consumption was a little over half a serving per week.
Out of the 925 participants, 245 developed Alzheimer’s. After accounting for factors that could influence the data, such as age, physical activity, education level, and other foods that boost brain health (think leafy greens), the team confirmed their theory. Participants who consumed one or more servings of strawberries per week had a 34 percent lower risk of developing the disease as compared to those who ate no strawberries or just one serving per month.
The Power of Antioxidants and Flavonoids
The researchers strongly believe that the health benefits of strawberries come from their antioxidants and flavonoids. Those include vitamin C and two flavonoids known as pelargonidin and cyanidin. Pelargonidin is also an anthocyanidin, or a plant pigment that gives the berry its bright color. Cyanidin is another plant pigment that creates a red hue.
Participants who had the highest intake of the flavonoid pelargonidin were 44 percent less likely to develop Alzheimer’s as compared to those with the lowest intake. Strawberries accounted for 75 percent of the participants’ pelargonidin intake.
Why do pelargonidin and other nutrients in strawberries reduce cognitive decline? According to the researchers, antioxidants and flavonoids may reverse the aging of neurons. This might happen because the plant compounds lower oxidative stress and neurotoxicity. Oxidative stress occurs when free radicals, or highly reactive molecules, damage cells and other molecules in the body. Neurotoxicity occurs when toxic substances damage the normal activity of neurons.
Previous studies back up these findings. Research published in The Journal of Neurochemistry found that antioxidants and flavonoids can cross the blood-brain barrier and directly improve the health of neurons. (The blood brain barrier is a physical and functional barrier that keeps out bacteria, fungi, viruses, and parasites that may circulate in the bloodstream.) In addition, one study from Molecular Aspects of Medicine showed that flavonoids boosted the memory of mice suffering from Alzheimer’s.
Boosting Your Strawberry Intake
Improving your brain health is a great excuse to eat more strawberries! The USDA notes that adult women should eat between 1 ½ to 2 cups of fruit each day. However, you don’t have to eat strawberries every day to reap the benefits. Just one cup a week is enough to benefit your cognition, according to the study. That’s about eight large strawberries.
Though fresh strawberries are not in season, you may still see them year-round at your local grocery store. Frozen, unsweetened strawberries provide similar benefits. (Plus, frozen berries are harvested at their peak.) Just keep in mind that frozen berries have a slightly lower concentration of antioxidants and flavonoids, so you may want to eat a little more than a cup to get the same level of nutrients. Whether you use them to top your oatmeal or slice them onto a bed of arugula, strawberries will add a pop of flavor and brain-healthy nutrients to any meal.