Doctors emphasize that one of the smartest things you can do for your heart is know and manage your numbers — blood pressure, BMI, cholesterol, and blood sugar. But here’s an unfortunate truth: The blood pressure reading that’s rattled off during your appointment may not be accurate.

It’s probably not your doctor’s fault. Blood pressure is temperamental. Lots of factors can result in an off measurement, meaning you can potentially end up with a misdiagnosis. “People might get over-treated or under-treated if their blood pressure isn’t measured correctly in the office,” says Jordana Cohen, M.D., assistant professor of medicine at the University of Pennsylvania’s Perelman School of Medicine. In other words, you could be put on meds you don’t need or prescribed a dose higher or lower than necessary. Follow this blood pressure checklist to make sure you walk away with the right reading.

Take a breather.

Rushing to your appointment can elevate blood pressure, which may throw off your reading. If you can, calmly sit still in the waiting room for five minutes, then keep quiet while your pressure is taken; even small talk can up your systolic reading (the top number) by 10 to 15 mm Hg. If you get anxious in medical settings — known as white coat syndrome — speak up, because this can lead to a higher reading than when you’re not stressed.

Prep in advance.

Skip the coffee until after your appointment, as caffeine may cause blood pressure to spike temporarily. And hit the bathroom before heading into the exam room — a full bladder can stimulate an adrenaline-like hormone that often raises blood pressure.

Watch your posture.

Sit with your feet flat on the floor — crossed legs or dangling feet can bump systolic results up. Be sure your arm is supported and at heart level, as diastolic pressure (the bottom number) is affected by arm position, says Dr. Cohen. Ask if you can sit in a chair instead of on the exam table — this can help keep your arm supported at the correct height.

Do an at-home check.

To monitor your blood pressure at home, try a trustworthy device like the Omron ReliOn BP200 monitor. High reading? Here are expert-approved ways to lower your blood pressure without medication.

Credit: Prevention

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