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Decoding Your Blood Pressure Reading

    • Here’s what you need to know about your blood pressure numbers courtesy of Dr. Gary Milechman, a cardiologist with California Pacific Medical Center in San FranciscoOpens new window.

      1. What are the numbers in a blood pressure reading?

      Readings will have two numbers – the systolic and diastolic pressure.

      The first and higher of the two numbers is the systolic pressure, measuring the full pressure when the left ventricle of the heart pushes out blood through the arteries into the body.

      The lower of the two numbers is the diastolic pressure, measuring the pressure within the arteries when the ventricles are “at rest” before the next pulse of blood is pushed through.

      2. Is one blood pressure number more important than the other?

      Dr. Milechman says no – both numbers provide valuable information about the state of your arteries.

      3. What is a normal blood pressure reading – and what is high blood pressure?

      The guidelines for ideal blood pressure are:

      • 120/80 or less: Normal blood pressure reading. No problems identified.
      • 120-139/80-89: Pre-hypertension. This measure is a warning sign of potential problems, and a doctor will recommend you begin lifestyle changes to reduce your pressure. (See 7 Ways to Lower Blood Pressure.)
      • 140/ 90 and above: Hypertension, or high blood pressure. These numbers indicate you should find a way to reduce your blood pressure, which may involve lifestyle changes and/or medications.
      • 180/100 or above: Readings this high can be dangerous and should be addressed immediately by a physician.

      4. Can blood pressure numbers be too low?

      Some people do have blood pressure numbers lower than the standard 120/80. Dr. Milechman notes that as long as they feel OK – no dizziness, light-headedness or fainting – then nothing needs to be done.

      When someone is taking blood pressure medications, these lower readings may indicate the need to adjust medication, especially if the diastolic pressure is lower than 60.

      5. How should I take a blood pressure reading?

      If you are monitoring your own blood pressure at home, remember that pressures vary during the day, especially based on activity and exercise. You should always take the reading after sitting quietly for five minutes. Also, be sure to hold still (no talking or moving) while the pressure cuff is measuring your blood pressure.

      6. So I’m healthy and feel fine. Do I need to go have a blood pressure reading?

      Since hypertension or high blood pressure has no symptoms you won’t know if you don’t check. Dr. Milechman suggests that even healthy young people test their blood pressure at least once a year – at the doctor’s office, at home, or in a grocery or drug store machine. If your parents have high blood pressure or heart disease, be more vigilant about your own health.

      If you get several high readings in a row, it’s time to see your doctor for a most accurate reading and a discussion of your own health.