Recent findings point to possible harm from very low diastolic blood pressure, the second number in a blood pressure reading.
Current blood pressure guidelines define an ideal reading as less than 120/80 millimeters of mercury (mm Hg). According to some research, an even lower systolic value (the first number in the reading) may help prevent even more heart attacks and strokes. But more aggressive treatment to lower systolic blood pressure makes sense only as long as you don’t develop symptoms such as feeling lightheaded or dizzy.
However, when it comes to diastolic pressure (the second number in the reading), lower is not necessarily better. A study published the Feb. 1, 2021, in JAMA Network Open found that a very low diastolic blood pressure — less than 60 mm Hg — was linked to an increased risk of heart attack and stroke in people at high cardiovascular risk.
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About the Author
Julie Corliss, Executive Editor, Harvard Heart Letter
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