Many older adults worry about memory loss and other changes in thinking as they age. Most of the time, these changes are mild and a normal part of getting older—such as occasionally forgetting names or where you put your keys.
However, more serious memory problems that interfere with daily life—like getting lost, struggling to use a phone, or forgetting how to drive—could be signs of something more concerning.
In a new study from the University of Washington, researchers reviewed over 150 scientific papers and found that a key factor in keeping the brain healthy during aging is maintaining a strong and properly functioning blood-brain barrier.
The blood-brain barrier is a network of blood vessels that protects the brain. It acts like a filter, allowing only certain substances to pass through while blocking others. This is important because the brain is extremely sensitive and needs to be protected from harmful substances in the blood.
At the same time, the brain still needs nutrients and communication with the rest of the body, so the barrier allows some helpful substances to pass through in a controlled way. It also helps remove waste and toxins from the brain.
As people age, this barrier can start to leak. In healthy aging, this leak is very small and is linked to mild forgetfulness—what many scientists call “benign” memory changes. These are not considered harmful and happen to most people as they get older.
However, the researchers found that in people with certain risk factors—such as those who carry the ApoE4 gene, which is known to increase the risk of Alzheimer’s disease—the leak in the blood-brain barrier becomes more severe.
This gene also makes it harder for the brain to clear away a substance called amyloid beta-peptide, which can build up and form plaques in the brain. These plaques are a well-known feature of Alzheimer’s disease.
The team also discovered that with aging, two types of brain cells involved in the blood-brain barrier begin to change: pericytes and astrocytes.
Pericytes help maintain the barrier’s structure and function. When they are lost or damaged, the barrier becomes more leaky. Astrocytes, on the other hand, may become overactive with age and contribute to inflammation in the brain.
A major takeaway from the study is that protecting pericytes could help keep the blood-brain barrier healthy and may reduce memory problems. Some research suggests that things like regular exercise, eating fewer calories, and possibly certain medications like rapamycin may help preserve pericyte health—and, in turn, help the brain stay healthier for longer.
The review also highlighted that a breakdown in the blood-brain barrier doesn’t just relate to memory problems. It can also play a role in other serious health conditions, including multiple sclerosis, diabetes, and Alzheimer’s disease.
This study, published in Nature Aging and led by Dr. William Banks and his team, provides new insight into how and why memory can change with age. It also offers hope that by focusing on protecting the blood-brain barrier, especially through healthy lifestyle choices, we might be able to keep our brains healthier as we grow older.
If you care about brain health, please read studies about how the Mediterranean diet could protect your brain health, and Omega-3 fats and carotenoid supplements could improve memory.
For more information about brain health, please see recent studies about antioxidants that could help reduce dementia risk, and higher magnesium intake could help benefit brain health.
Copyright © 2025 Knowridge Science Report. All rights reserved.
