Stunning as it may sound, nearly half of Americans ages 20 years and up – or more than 122 million people – have high blood pressure, according to a 2023 report from the American Heart Association. And even if your numbers are normal right now, they are likely to increase as you age; more than three-quarters of Americans age 65 and older have high blood pressure.

Also known as hypertension, high blood pressure is a major risk factor for heart disease and stroke.

Our research has found that most Americans don’t know the normal or healthy range for blood pressure – yet strikingly, they think they do. And that is cause for serious concern.

We are a health communications expert and a cardiologist. Together with our health communication collaborators, we surveyed more than 6,500 Americans about their knowledge of blood pressure. They were recruited through the Understanding America Study, a nationally representative sample of U.S. residents.

In our new study, published in January 2023, we found that 64% expressed confidence in their understanding of blood pressure numbers – but only 39% actually knew what normal or healthy blood pressure is. A healthy diet, more exercise and less salt and alcohol are all ways to improve your blood pressure numbers.

Such false confidence can be harmful because it may prevent people from seeking care for high blood pressure. After all, if you think it’s normal, why bother talking to your doctor about your blood pressure?

Part of the reason for this overconfidence begins in the doctor’s office. Typically, a nurse brings over a blood pressure cuff, straps it on your upper arm and takes a reading. The nurse may announce the result, remove the cuff and record it for the doctor.

When the doctor arrives, the session may well move on to other matters without a word about the blood pressure reading. This likely happens because your doctor wants to focus on how you’re feeling and why you’re there. But as a result, you may leave your appointment thinking your blood pressure is fine, even if it’s not.

About 70% of Americans will have high blood pressure in their lifetimes. What’s more, only 1 in 4 patients with hypertension have their blood pressure under control. And because high blood pressure usually has no symptoms, you can have it without knowing it.

To lower your risk of heart attacks and strokes, it’s critical to understand your blood pressure readings. This is especially true for patients with conditions such as heart disease, kidney disease and diabetes.

Blood pressure is reported with two numbers. The first number is your systolic blood pressure; it measures the pressure in arteries when the heart beats. The second number, your diastolic blood pressure, measures the pressure in your arteries between heartbeats.

Normal or healthy blood pressure is less than 120/80 millimeters of mercury (mm Hg) for adults. This is a unit of measurement that stems from early blood pressure monitors, which looked at how far your blood pressure could push a column of liquid mercury. For most patients, lower tends to be better.

Stage 1 hypertension, which is the lower stage of high blood pressure, begins at 130/80. Stage 2 hypertension, which is the more severe stage of high blood pressure, begins at 140/90. Both numbers are critically important, because every increase of 20 millimeters of mercury in systolic blood pressure, or 10 in diastolic blood pressure, doubles a person’s chances of dying from a heart attack or stroke.

To avoid false confidence, ask about your blood pressure at every doctor’s visit, and find out what the numbers mean. If your blood pressure is above the normal or healthy range, then the American Heart Association recommends the following 10 tips.

High blood pressure is a silent killer. Being proactive and knowing your numbers can be a lifesaver.

Wändi Bruine de Bruin, Professor of Public Policy, Psychology and Behavioral Science, USC Sol Price School of Public Policy, USC Dornsife College of Letters, Arts and Sciences and Mark Huffman, Professor of Medicine, Washington University in St Louis

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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