Blood pressure is one of the most important numbers when it comes to heart health.
It helps show how hard your heart is working to move blood through your body. Blood pressure is written as two numbers, like 120/80.
The top number is called systolic pressure. It shows how much pressure is in your blood vessels when your heart pumps blood out.
The bottom number is called diastolic pressure. It shows the pressure when your heart is resting between beats and filling up with blood.
For a long time, doctors and researchers have focused more on the top number—systolic pressure—when looking at the risk of heart disease and stroke. Because of this, the lower number, diastolic pressure, has sometimes been overlooked.
But a new study from Kaiser Permanente is changing that view. The study looked at over 36 million blood pressure readings from 1.3 million adults in Northern California. These readings were collected over almost ten years.
The researchers found that both systolic and diastolic pressure are important. High numbers in either one can increase the risk of heart problems and strokes. While the systolic number may have a slightly stronger link to heart disease, the diastolic number also matters and should not be ignored.
This was true no matter how high blood pressure was defined. Some people use the older guideline of 140/90 to define high blood pressure, while newer guidelines use 130/80. Either way, the results stayed the same—both numbers were linked to higher health risks.
This means that when doctors check your blood pressure, they should look carefully at both numbers, not just the top one. It’s a reminder that both parts of the reading can give clues about your heart health.
The study supports newer healthcare guidelines that suggest aiming for lower blood pressure overall, especially for people who are more likely to get heart disease.
The research was led by Dr. Alexander C. Flint and was published in the New England Journal of Medicine. It gives us a better understanding of how blood pressure affects our health and shows that we need to pay attention to the full picture—not just one number.
If you care about heart health, please read studies about Changing blood pressure readings is a hidden sign of heart disease and findings of Common type 2 diabetes drugs may raise heart risk.
For more information about heart health, please read studies about Scientists find root cause of heart rhythm disorders and findings of Warning signal from the kidneys can predict future heart failure risk.
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