That's the finding of a new report that looked at five-year's worth of data for more than 400 patients.
Experts conclude that the current practice of screening at every visit to the doctor's office may need to be limited to once a year.
They believe multiple screenings result in more people being mistakenly diagnosed and unnecessarily treated for high blood pressure.
Mayo Clinic researchers found taking fewer readings would weed out almost half of the false positives.
