High blood pressure is widely known to affect the heart, but scientists are increasingly discovering that it can also have a major impact on the brain.
A new study from researchers at the University of Miami suggests that one particular number in a blood pressure reading may be especially important for brain health, particularly for people over the age of 50.
When doctors measure blood pressure, they record two numbers. The first number, called systolic pressure, shows the pressure in the arteries when the heart is actively pumping blood.
The second number, known as diastolic pressure, shows the pressure in the arteries when the heart relaxes between beats. Blood pressure is written as systolic over diastolic, such as 120 over 80.
For many years, most research and medical advice have focused on the systolic number, the top value. Doctors have known that high systolic blood pressure can damage blood vessels and increase the risk of heart attack, stroke, and other serious conditions.
However, the new study suggests that the lower number—the diastolic pressure—may also play a critical role in protecting the brain.
The research team examined the health data of more than 1,200 adults who were aged 50 and older. Their goal was to understand how different levels of blood pressure might influence the brain’s structure and long‑term health.
One part of the brain that the scientists paid close attention to is known as white matter. White matter is made up of bundles of nerve fibers that connect different regions of the brain. These fibers act like communication highways, allowing information to travel quickly between brain cells.
When white matter is healthy, the brain can process information efficiently. But when white matter becomes damaged, communication between different brain regions can slow down or break down. This can lead to problems with memory, thinking, balance, and movement. In severe cases, white matter damage has been linked to stroke and dementia.
To measure this type of damage, researchers look for what are called white matter lesions. These lesions are small areas of scarring in the brain that can be seen on brain scans. They appear when tiny blood vessels in the brain become damaged over time.
White matter lesions are actually quite common in older adults. Studies have shown that by the age of 60, around 10 to 20 percent of people already have some of these brain scars. As people age further, the number increases. Among people in their 90s, most individuals show at least some degree of white matter damage.
Because these lesions are strongly linked to cognitive decline, falls, and stroke, scientists are eager to understand what factors increase or reduce the risk of developing them.
The results of the University of Miami study revealed a clear pattern. Participants who had lower diastolic blood pressure—especially readings below 80—tended to have fewer white matter lesions in their brains.
In contrast, participants with higher diastolic blood pressure, particularly those with readings above 90, were more likely to have larger and more numerous brain lesions. In certain areas of the brain, the size of these lesions was noticeably smaller among people whose diastolic pressure remained lower.
This finding suggests that controlling the lower number in blood pressure readings may be an important way to protect brain health as people age.
The discovery is important because previous research has mainly focused on systolic pressure, the top number. While systolic pressure is still a major factor in cardiovascular health, the new study highlights that diastolic pressure should not be ignored.
According to the researchers, keeping diastolic blood pressure under control may help protect the tiny blood vessels in the brain. These small vessels supply oxygen and nutrients to brain tissue. When they are exposed to constant high pressure, they can become damaged, which may lead to the formation of white matter lesions.
The study was led by researcher Michelle R. Caunca and her colleagues. Their findings were published in the scientific journal Stroke.
The results emphasize the importance of monitoring blood pressure regularly, especially for people over the age of 50. Maintaining healthy blood pressure levels may not only protect the heart but also help preserve brain function and reduce the risk of stroke and dementia.
Doctors often recommend several lifestyle habits that can help keep blood pressure within a healthy range. These include regular physical activity, eating a balanced diet rich in fruits and vegetables, limiting salt intake, managing stress, and getting enough sleep.
Regular medical check‑ups can also help detect blood pressure problems early, allowing people to take steps to protect both their heart and their brain.
As scientists continue to learn more about how blood pressure affects the brain, studies like this provide valuable clues about how people can maintain cognitive health as they grow older.
If you care about blood pressure, please read studies about blood pressure drug that may increase risk of sudden cardiac arrest, and these teas could help reduce high blood pressure.
For more health information, please see recent studies about nutrient that could strongly lower high blood pressure, and results showing this novel antioxidant may help reverse blood vessels aging by 20 years.
Copyright © 2026 Knowridge Science Report. All rights reserved.
