Most people have had their blood pressure checked during a doctor’s visit. The reading usually shows two numbers, such as 120 over 80.
For many years, doctors and patients paid most attention to the top number. This number is called systolic blood pressure. It measures how strongly the heart pushes blood through the arteries when the heart beats.
The lower number is called diastolic blood pressure. It measures the pressure in the arteries when the heart is resting between beats and filling with blood again.
For a long time, many experts believed the top number was the most important sign for predicting heart disease and stroke. High systolic blood pressure has been strongly linked to dangerous health problems, especially in older adults.
Because of this, the lower number was sometimes seen as less important. But a huge new study suggests that this idea may not tell the full story.
Researchers from Kaiser Permanente, one of the largest healthcare systems in the United States, wanted to better understand how both blood pressure numbers affect health. To do this, they examined more than 36 million blood pressure readings collected from about 1.3 million adults living in Northern California.
The information was gathered over nine years, from 2007 to 2016. Because of the massive amount of data, this became one of the largest blood pressure studies ever carried out.
The researchers discovered something important. They found that both blood pressure numbers matter when it comes to predicting the risk of serious health problems such as heart attacks and strokes.
The top number still had the strongest connection to heart disease risk, but the lower number also played a clear and important role. In other words, doctors should not ignore the bottom number when checking a patient’s blood pressure.
This finding is important because blood pressure affects millions of people around the world. High blood pressure, also called hypertension, often has no clear symptoms. Many people feel completely normal even when their blood pressure is dangerously high. That is why it is often called a “silent killer.”
Over time, high blood pressure can damage blood vessels and organs throughout the body. It can increase the risk of heart disease, stroke, kidney disease, and even memory problems later in life.
The study also looked at different ways doctors define high blood pressure. In the past, many health experts used 140 over 90 millimeters of mercury, written as mm Hg, as the main cut-off point for high blood pressure.
More recently, newer guidelines lowered the target to 130 over 80 mm Hg. These stricter guidelines were created because research showed that even slightly raised blood pressure can increase the risk of heart disease over time.
The new study found that the lower blood pressure number still mattered no matter which guideline was used. This means that keeping both numbers under control is important for protecting long-term health.
The findings support the newer blood pressure guidelines that encourage people to aim for healthier blood pressure levels earlier rather than waiting until the numbers become very high. Doctors now understand that preventing damage early can greatly reduce the chances of future illness.
The research was led by Dr. Alexander C. Flint and was published in the New England Journal of Medicine, one of the world’s most respected medical journals. The study adds to growing evidence that blood pressure should be viewed more carefully and completely.
For everyday people, the message is simple. Blood pressure checks are not just routine tests done during a medical visit. They can provide valuable information about the health of the heart and blood vessels.
Both numbers in a blood pressure reading tell part of the story. If either one stays too high for too long, it may raise the risk of serious disease later in life.
There are many ways people can help keep their blood pressure in a healthy range. Regular exercise, healthy eating, reducing salt intake, sleeping well, avoiding smoking, and managing stress can all help.
Some people may also need medication recommended by their doctor. Even small lifestyle changes can make a difference over time.
Many people only remember the top blood pressure number and forget the lower one. But this large study reminds us that the lower number is also important and should not be ignored.
As science continues to improve our understanding of health, doctors can give better advice and patients can make smarter choices to protect themselves.
If you do not know your blood pressure numbers, it may be worth asking during your next medical visit. Understanding both numbers could help you take better care of your heart, lower your risk of stroke, and improve your chances of staying healthy for many years to come.
If you care about high blood pressure, please read studies about breakfast for better blood pressure management, and the gut feeling that lowers blood pressure.
For more health information, please see recent studies about how the dash diet helps lower blood pressure, and how to eat your way to healthy blood pressure.
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