The Proper Way to Take Blood Pressure

Learn how your doctor should take your blood pressure to get an accurate reading

I am 100 percent for regular blood pressure screenings—as long as they're done properly. Unfortunately, taking blood pressure has become so routine that sloppy, inaccurate procedures cause many people to be incorrectly diagnosed as having high blood pressure when their pressures are actually normal. Researchers at the VA Medical Center in Long Beach, California, estimate that 20 to 30 percent of patients diagnosed as hypertensive have normal blood pressure.

To get the most accurate reading at your next blood pressure screening, insist the procedure be done properly. Follow these tips:

• Do not exercise or eat for 30 minutes before having your blood pressure taken. (Even a cup of coffee can affect readings for several hours after you drink it.)
• Rest at least five minutes beforehand. You should feel comfortable and relaxed in your surroundings.
• Have your reading taken in the morning because biological rhythms naturally cause pressures to be higher in the afternoons and evenings.
• Remove all clothing from the waist up. Just rolling up your shirtsleeve can act like a tourniquet and cause false readings.
• Ask that your blood pressure include readings taken while you are lying, sitting, and standing. Readings often skyrocket as you change positions, which may signal weak adrenal glands—not high blood pressure.
• Make sure your elbow is at the same level as your heart. Every doctor and nurse is taught this, but very few check it. An elbow that is even a couple of inches below the heart can make the reading as much as 17 points higher than it should be. There's no telling how many people have "low elbow" instead of high blood pressure!

Location of the heart 

• Have your blood pressure taken three times with at least a one-minute rest between each one.
• Ask if an ambulatory monitoring machine is available. These machines use either an automatic inflatable cuff or small sensor that records blood pressure inside an artery every 15 minutes over a 24-hour period. This eliminates the 20- to 30-mm Hg jump in pressure that often occurs when a patient is in a doctor's office waiting for a blood pressure reading (called "white coat hypertension"). Most doctors don't use ambulatory blood pressure monitors yet, but it would be well worth your time to find one who does.

More Dr. Williams Advice on Blood Pressure

• Which foods to eat and which foods to avoid for lowering blood pressure
• Lifestyle habits that lower blood pressure naturally
• Vitamins and minerals that complement blood pressure–lowering programs
• Why you should be wary of conventional high blood pressure treatments