Your Apple Watch can now alert you if you’re showing signs of hypertension—a new feature cleared by the U.S. Food and Drug Administration on Sept. 11.
The feature does not diagnose high blood pressure or take blood pressure readings. Instead, it relies on the watch’s optical heart sensor to analyze how the blood vessels contract and expand in response to the heart’s pumping. Over time, the data collected can reveal signs of hypertension and trigger an alert. Users can see a report generated by the data and consult their doctor for further evaluation.
The hypertension feature will soon be available on all Apple Watch Series 9 models and Apple Watch Ultra 2 models—plus their newer versions—in more than 150 countries.
According to the American Heart Association (AHA), about half of U.S. adults have high blood pressure, and a significant proportion of them don’t know they have the condition. Only about a quarter are keeping their blood pressure under control. Uncontrolled hypertension can lead to more strain on the blood vessels, which could weaken the heart and lead to serious health problems like strokes, heart attacks, and kidney disease. Health officials have estimated in the past that these health consequences of hypertension cost about $131 billion annually.
The clearance for the Apple Watch feature was based on a series of studies involving thousands of adults. In one study, more than 2,000 adults without hypertension wore the watch for 12 hours a day for almost a month and also measured their blood pressure with a blood pressure cuff every day, twice a day. The study showed that the Apple Watch’s hypertension notification was as accurate as the cuff in detecting signs of high blood pressure.
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Awareness and early diagnosis can help bring blood pressure under control before it leads to more lasting and damaging effects on the body, says Dr. Daniel Jones, chair of the writing committee for the 2025 AHA and American College of Cardiology (ACC) High Blood Pressure Management Guidelines (who was not involved in the creation of the Apple Watch feature). “We’ve known for a long time that high blood pressure is the major cause of heart disease, stroke, and major chronic kidney disease,” he says. “And recently there is validation of data showing that lowering blood pressure also reduces the risk of dementia.” That makes it crucial for even young adults “to have their blood pressure measured and to know their blood pressure at least once a year with a validated device.”
People can control hypertension with dietary changes, such as reducing their salt intake; by losing weight; and increasing physical activity to strengthen the heart and vessels. Medications can also help in many cases.
Devices like the Apple Watch and its latest feature are welcome additions to improving health, says Jones, but he cautions that in the case of blood pressure, such devices are not yet considered validated ways to measure and monitor blood pressure by the AHA and ACC. That means that the information they provide should be viewed with a caveat: It could be helpful, but, he says, people should not rely on it as their only source of information on their blood pressure.
“Understanding whether blood pressure is normal or not normal is much more complex than detecting irregular heart rhythms,” he says. “I would not recommend that any patient depend on a watch-based device for warnings about blood pressure, unless it’s been validated by an external [medical] organization.”
The AHA and ACC guidelines currently recommend that otherwise healthy adults get blood pressure measured at least once a year, either in a doctor’s office or pharmacy, with a validated device like a blood-pressure cuff or by using an at-home kit approved for measuring blood pressure.
If people use the Apple Watch hypertension feature, Jones recommends verifying the information with one of these validated tools. That way, people can avoid false-positive or false-negative readings.
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