What's the right blood pressure?

Numerous studies have shown that the lower your blood pressure, the greater the heart health benefits. But that still leaves a question: what is the "best" blood pressure number for you? Unfortunately, it's complex, and the answer depends on several factors.

U.S. guidelines define normal blood pressure as less than 120/80 millimeters of mercury (mm Hg). Elevated blood pressure is considered 120 to 129 systolic (top number) and less than 80 diastolic (bottom number). High blood pressure (Stage 1 hypertension) is 130 to 139 systolic or 80 to 89 diastolic. A reading of 140/90 mm Hg or higher is considered Stage 2 hypertension.

"These broad definitions are great, but what's more important is to provide an individual assessment and look at a person's health condition, lifestyle, family history, and goals to determine what's a practical blood pressure target," says Dr. Randall Zusman, director of the Division of Hypertension at Harvard-affiliated Massachusetts General Hospital's Heart Center. "What is the best number for one person is often different for another."

Targeting the goal

While normal blood pressure of less than 120/80 mm Hg is a good goal, Dr. Zusman believes that any number below 130/80 mm Hg is sufficient for most people. "Individuals may have trouble driving down their number to 120/80 or lower and keeping it there," he says. "So, if a person can get down to 128 or 127, and keep it there, I consider that a victory especially if their blood pressure previously had been difficult to control."

There are exceptions. People with certain health conditions may benefit from lowering their blood pressure below 120/80 mm Hg. These may include people with diabetes, high cholesterol, or regular episodes of angina (chest) pain.

A study in the July 2024 issue of The Lancet also found that people diagnosed with Stage 2 hypertension (140/90 mm Hg or higher) had a lower risk of heart attack or stroke if they brought their blood pressure below 120 mm Hg compared with those who reduced their blood pressure to only 135 mm Hg.

However, dipping too far below 120 mm Hg — no matter your condition — may cause dizziness or lightheadedness, which can increase the risk for falls. "Depending on how people react as they lower their blood pressure, they may be better suited to stay in the 120 to 129 range," says Dr. Zusman.

Lower your number

If your doctor recommends working to lower your blood pressure, the first step is almost always making lifestyle changes, such as losing excess weight, avoiding high salt intake, adopting a heart-healthy diet like the DASH or Mediterranean diet, and increasing exercise. Some over-the-counter drugs can raise blood pressure and should only be used if absolutely necessary, such as decongestants, some cold and flu medicines, and nonsteroidal anti-inflammatories — ibuprofen (Advil, Motrin), and naproxen (Aleve).

"Implementing lifestyle changes can help reduce blood pressure by several points," says Dr. Zusman. "In some cases, that may be enough. However, there are limits to their overall effect, and people may have trouble following them regularly."

This is why medication is often used alongside lifestyle changes. Common drugs for lowering and managing high blood pressure include calcium-channel blockers, ACE inhibitors, angiotensin-receptor blockers (ARBs), and diuretics, given either individually or in combination. Calcium-channel blockers help blood vessels relax, ACE inhibitors and ARBs block a key hormone pathway involved in raising blood pressure, and diuretics eliminate excess sodium and water from the body.

People don't have to take medication indefinitely, says Dr. Zusman. "As your blood pressure improves, and you adopt healthy lifestyle habits, your doctor may reduce your dose, or you may even eventually be able to go off one of them."

Monitoring your number

No matter your blood pressure goal, you should invest in a home blood pressure monitor to check your number regularly.

Many home monitors cost about $50 to $100. Here are a few tips for selecting a proper one:

• Choose a monitor that appears on the U.S. Blood Pressure Validated Device Listing.
• Look for a device with a large, easy-to-read display and an arm cuff that inflates automatically. (Wrist or finger cuffs are not considered reliable.)
• Measure the circumference of your upper arm midway between your elbow and shoulder to ensure a proper fit. Most home monitor cuffs can accommodate arm circumferences of 9 to 17 inches, but smaller and larger cuffs are available. A cuff that is too small or too large won't be accurate.

To ensure an accurate reading, empty your bladder beforehand and wait at least 30 minutes after consuming caffeine or alcohol or exercising. Sit in a chair with your feet on the floor and your arm supported so your elbow is at heart level.

"Bring your monitor and a copy of your home readings to your doctor's office to observe whether you are using it correctly and compare your home measurements to the numbers your doctor finds," says Dr. Zusman.

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