High blood pressure, also known as hypertension, occurs when the pressure of the blood flowing against the artery walls is above the normal range. Blood pressure is measured in two sets of numbers. The first number is the systolic reading, which is the pressure when the heart is beating. The second number is the diastolic number, the pressure when the heart is resting. High blood pressure occurs when the systolic reading is at 140 or higher and/or the diastolic reading is 90 or above.
Additional Resources
- MedlinePlus
- National Institutes of Health
- Centers for Disease Control and Prevention
- Eunice Kennedy Shriver National Institute of Child Health and Human Development
- U.S. Department of Health & Human Services
- WebMD
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