Blueberries Seen to Ease Cognitive Decline, a Key Alzheimer’s Symptom

Blueberries, a “super fruit” known to decrease the risk of cancer and heart disease, may also be of benefit against Alzheimer’s disease, according to findings recently presented at the 251st National Meeting & Exposition of the American Chemical Society (ACS).

Blueberries are loaded with antioxidants, which, according to researchers, could help prevent the cognitive decline that is a hallmark of Alzheimer’s. “Our new findings corroborate those of previous animal studies and preliminary human studies, adding further support to the notion that blueberries can have a real benefit in improving memory and cognitive function in some older adults,” Robert Krikorian, PhD, the study’s lead researcher, said in a press release. The beneficial effects of blueberries, he added, could be due to the presence of anthocyanins, flavonoids shown to improve cognition in animals.

Following up on earlier clinical trials, Dr. Krikorian and colleagues at University of Cincinnati Academic Health Center conducted two studies in humans. The first included 47 adults, ages 68 and older, with mild cognitive impairment. Participants received either freeze-dried blueberry powder (equivalent to a cup of berries) or a placebo powder once daily for a period of 16 weeks.

“There was improvement in cognitive performance and brain function in those who had the blueberry powder compared with those who took the placebo,” Dr. Krikorian said. “The blueberry group demonstrated improved memory and improved access to words and concepts.” The team also conducted functional magnetic resonance imaging (fMRI), which showed increased brain activity in those who ingested the blueberry powder.

In the second study, researchers recruited 94 people, ages 62 to 80, randomized into four groups to receive either blueberry powder, fish oil, fish oil and powder, or placebo. These participants didn’t have objective cognitive issues, but felt a decline in memory capacity.

“The results were not as robust as with the first study,” Dr. Krikorian said. “Cognition was somewhat better for those with powder or fish oil separately, but there was little improvement with memory.” Functional MRI results were also not as significative in those receiving blueberry powder.

According to Dr. Krikorian, findings from both studies suggest that blueberries are more efficient to treat patients with cognitive impairments, but may not show a measurable cognitive benefit in those who only have minor memory problems, or have not yet developed cognitive issues.

Researchers soon plan to study the effects of blueberry consumption in adults, ages 50 to 65, who are at risk of developing Alzheimer’s.