When you visit the doctor and get your blood pressure checked, the machine wraps around your arm, squeezes it, and then gives two numbers.
Most people know that these numbers are important for heart health, but now scientists are finding they might be just as important for your brain.
A new study from the University of Miami, published in the journal Stroke, looked closely at the second number, called diastolic blood pressure. This number measures the pressure in your blood vessels when your heart is resting between beats.
The first number, called systolic blood pressure, shows the pressure when your heart is actively pumping blood. Most doctors focus more on the top number, but this study shows we shouldn’t ignore the bottom number.
The research was led by Michelle R. Caunca and her team. They studied 1,205 people who were all 50 years old or older. Each person had an MRI scan of their brain so the researchers could look for small scars, known as white matter lesions.
These scars can affect how the brain sends and receives signals. They are linked to problems with movement, balance, memory, and thinking. In some cases, they can lead to a higher risk of stroke, dementia, and even falling.
Here’s the interesting part: people with lower diastolic blood pressure—less than 80—had fewer of these brain scars. On the other hand, people with higher diastolic blood pressure—above 90—had more scars. This finding was surprising because people usually worry about high systolic blood pressure when they think about brain or heart problems.
White matter is a special part of the brain made of nerve fibers. It acts like a communication highway, helping different parts of the brain talk to each other. When scars or lesions appear in this area, those messages can get blocked. This can cause serious problems, especially in older adults.
By the time people reach the age of 60, about 1 in 5 already have some white matter lesions. These scars become even more common as people age, and nearly everyone over 90 may have them.
The researchers found that the location of these scars in the brain matters too. Scars in an area called the periventricular region are more strongly linked to problems with memory and thinking.
This study helps us understand that blood pressure, especially the lower number, might affect more than just our heart. It might also be a key to protecting our brain as we grow older.
So it’s a good idea to check your blood pressure regularly and talk with your doctor about what your numbers mean. Paying attention to that second number could help keep your brain healthier for longer.
If you care about high blood pressure, please read studies that early time-restricted eating could help improve blood pressure, and natural coconut sugar could help reduce blood pressure and artery stiffness.
For more health information, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
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