Most people know that blood pressure is an important sign of how healthy their heart and blood vessels are. It’s measured with two numbers. The top number, called systolic pressure, shows how hard the blood pushes against the artery walls when the heart beats.
The bottom number, called diastolic pressure, shows the pressure when the heart is resting between beats. For a long time, doctors have focused more on the top number because it’s closely linked to the risk of heart attacks and strokes.
But a new study from researchers at the University of Miami has found that the bottom number—the diastolic pressure—may also play a big role, especially in brain health.
The study shows that people with higher diastolic blood pressure may have more damage in their brains, which could lead to serious problems like memory loss, trouble thinking clearly, and a higher risk of falling.
The researchers looked at 1,205 people aged 50 and older. They used MRI scans to look for white matter lesions in the brain. These lesions are like tiny scars that form when small blood vessels in the brain are damaged.
They can slow down or block the messages the brain sends to the rest of the body. This can make it harder to walk, move, think clearly, or remember things. These lesions are also linked to a higher chance of having a stroke or developing dementia.
The study found that people with lower diastolic blood pressure—specifically, under 80—had fewer and smaller white matter lesions. In contrast, people with a diastolic reading over 90 had larger lesions in three key areas of the brain. This is important because some of these brain areas help with thinking and memory.
The researchers noted that one region, called the periventricular white matter, is especially important because damage there is more closely linked to cognitive problems like memory loss and confusion.
Until now, most studies have looked mainly at systolic blood pressure and its role in causing narrowed arteries and brain damage. This new research shows that diastolic pressure matters too—and possibly in different ways. Blood vessels in the brain supply different areas, and when they don’t work properly, it can lead to damage in specific places.
The study follows the American guidelines, which say a diastolic reading of 80 or more is considered high. The findings suggest that even slightly high diastolic pressure might raise the risk of brain damage over time. That means it’s important to pay attention to both blood pressure numbers, not just the top one.
This research was led by Michelle R. Caunca and her team and was published in the journal Stroke. It offers a fresh look at how managing blood pressure—especially the bottom number—could help protect the brain as people age.
If you’re over 50 or have concerns about your blood pressure, it’s a good idea to talk to your doctor. Managing blood pressure through a healthy diet, exercise, stress control, and, when needed, medication, could make a big difference not just for your heart, but for your brain as well.
If you care about high blood pressure, please read studies about potatoes and high blood pressure, and top 10 choices for a blood pressure-friendly diet
For more information about high blood pressure, please see recent studies about impact of vitamins on high blood pressure you need to know, and the powerful link between high blood pressure and a potassium-rich diet.
Copyright © 2025 Knowridge Science Report. All rights reserved.
