Everyday Health

Is Your Blood Pressure Accurate?

Originally published June 28, 2017

Last updated April 29, 2024

Reading Time: 3 minutes

Learn small hacks to make sure you’re getting the right readings.

Over time, your blood pressure readings can tell you a lot about your overall health. But even healthy people’s blood pressure readings can fluctuate in any given 24-hour period, as blood pressure is affected by many physiological factors. That’s why it’s important to know how you can get more accurate readings of your blood pressure.

High blood pressure can indicate some relatively serious health conditions. For example, plaque buildup in the arteries can cause blood pressure to increase, and lifestyle habits like smoking can constrict blood vessels, driving blood pressure up.

As that pressure increases, the heart has to work harder and may become enlarged, leading to a range of health problems. If left untreated, high blood pressure raises the risk of cardiac arrest (heart attack), heart failure, stroke, or kidney disease. That’s why it’s important to monitor your blood pressure regularly.

But according to the American Heart Association (AHA) and the American Society of Hypertension, it’s not as easy as you’d imagine to capture an accurate blood pressure reading on the basis of one or two measurements during a doctor’s visit. Instead, they recommend using home blood pressure monitoring to obtain a reliable estimate of your blood pressure between doctor visits. The AHA recommends only models with a cuff that goes around the arm, not the wrist or finger models.

“Patients should use an automated oscillometric device that measures blood pressure in the brachial artery (upper arm) and perform measurements in a quiet room after five minutes of rest, in the seated position with the back and arm supported,” says Rose Taroyan, MD, a family medicine physician at Keck Medicine of USC and clinical associate professor of family medicine at the Keck School of Medicine of USC. “At least 12 or 14 measurements should be obtained, with both morning and evening measurements taken, over a period of one week.”

Here are some additional tips:

1. Do not drink coffee, smoke, or exercise within 30 minutes before measuring.

2. After you put the cuff on, sit for a few minutes before checking blood pressure.

3. Don’t check only when you think the blood pressure readings will be good or only when you think they will be high. Check at random, normal times. Levels are usually lowest in the morning, and then rise steadily through the day.

4. Check your monitor’s accuracy at least once a year at the doctor’s office by comparing it to the office’s manual cuff.

5. Normal blood pressure is below 120/80 mmHg. Prehypertension is between 120/80 mmHg and 139/89 mmHg. Hypertension stage 1 is between 140/90 mmHg and 159/99 mmHg, and stage 2 is 160/100 mmHg or higher.

The following are some of the factors that lead to high blood pressure:

  • Advancing age
  • Obesity
  • Race (more common and severe and occurs earlier in life in African Americans)
  • High-sodium diet (intake of over 3 grams per day)
  • Excessive alcohol consumption
  • Physical inactivity
  • Diabetes and dyslipidemia (presence of other cardiovascular risk factors appear to be associated with an increased risk of developing hypertension)

If you do find that your blood pressure is consistently on the high side, try these tips. According to Taroyan, patients are advised to make the following lifestyle modifications for three month in order to lower their blood pressure:

  • Make dietary changes
  • Stay under 2 grams of sodium in your daily diet
  • Lose weight (BMI 18.5-24.9 kg/m2)
  • Engage in physical activity regularly (minimum of 30 minutes of aerobic exercise, five times a week)
  • Reduce or eliminate alcohol intake
  • Quit smoking

If these lifestyle modifications fail to lower your blood pressure, talk to your doctor about whether prescription blood pressure medications known as antihypertensives are right for you.


Ramin Zahed
Ramin Zahed is a Los Angeles-based author and journalist.