Most people have heard of blood pressure, but not everyone understands what the two numbers really mean. When you measure your blood pressure, you will see a top number and a bottom number.
The top number is called systolic blood pressure, and it shows the pressure in your arteries when your heart beats. The bottom number is called diastolic blood pressure, and it shows the pressure when your heart is resting between beats.
For many years, doctors have paid more attention to the top number because it is strongly linked to heart disease.
However, a new study suggests that the bottom number may also be very important, especially when it comes to brain health. This research shows that diastolic blood pressure could play a bigger role than many people realize in protecting the brain as we age.
The study was carried out by scientists from the University of Miami and was published in the journal Stroke. The researchers wanted to understand whether blood pressure is linked to small areas of damage in the brain. These areas are called white matter lesions. They are tiny scars that develop over time and can only be seen on brain scans such as MRI.
These brain lesions are often called “silent” because people usually do not notice them at first. However, they are not harmless. Over time, they can affect how the brain works. They are linked to problems with memory, thinking, balance, and movement. They also increase the risk of serious conditions such as stroke and dementia.
To study this, the researchers looked at more than 1,200 adults aged 50 and older. They measured each person’s blood pressure and used MRI scans to examine their brains. They focused on the size and location of white matter lesions to see if there was any connection with blood pressure levels.
The results were clear. People who had lower diastolic blood pressure, especially below 80, tended to have fewer and smaller brain lesions. On the other hand, people with higher diastolic blood pressure, particularly above 90, were more likely to have larger and more numerous lesions. These lesions were often found in important areas of the brain.
This finding is important because it shows that the bottom number of blood pressure is not just a minor detail. It may have a direct impact on the health of the brain.
Even though earlier research has already shown that high systolic pressure can damage blood vessels, this study adds new information. It shows that diastolic pressure may also contribute to brain changes.
White matter plays a key role in how the brain works. It contains nerve fibers that carry signals between different parts of the brain and between the brain and the rest of the body. When white matter becomes damaged, these signals do not travel as well. This can lead to slower thinking, poor balance, and a higher chance of falling.
The study also found that damage in a specific area of the brain, called the periventricular region, may be especially important. This area is very sensitive to changes in blood flow. When it is damaged, people are more likely to experience problems with memory and thinking.
As people get older, these brain changes become more common. By the age of 60, around 10% to 20% of people already have some white matter lesions. By the age of 90, most people show signs of them. This means that understanding how to protect the brain is very important for healthy aging.
The researchers explain that different parts of the brain receive blood from different arteries. Because of this, changes in blood pressure may affect some areas more than others. Even small increases in diastolic pressure can make a difference, depending on where the blood flow is affected.
This study highlights an important message. Both numbers in a blood pressure reading matter. Paying attention only to the top number may not give the full picture of your health. Keeping both systolic and diastolic pressure within a healthy range can help protect not only your heart but also your brain.
If you have not checked your blood pressure recently, it may be a good idea to do so. Regular check-ups and simple lifestyle changes, such as eating a healthy diet, staying active, and managing stress, can help keep your blood pressure under control. These steps may also help protect your memory, balance, and thinking ability as you grow older.
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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