Researchers Can Accurately Measure Blood Pressure Using Phone Camera

In the not so distant future, we may be able to apply preventative health measures using our smartphones, including measuring blood pressure just by taking a selfie video. Researchers from the University of Toronto have developed a new technology, termed “transdermal optical imaging,” that measures blood pressure using data garnered from video taken by an iPhone. More accurately, the phone’s optical sensors capture red light reflected from hemoglobin under the surface of the facial skin, which allows the transdermal optical imaging to measure changes in blood flow.

As odd as it sounds, the technology came about while trying to design a contactless lie detector, but in the process, the researchers discovered that the technology could be used to measure blood pressure.

“With lie detectors, it only benefits a very small group. But if I can measure blood pressure, we can benefit a lot of people. From the video captured by the technology, you can see how the blood flows in different parts of the face and through this ebb and flow of blood in the face, you can get a lot of information.” — Kang Lee, professor of applied psychology and human development

The researchers used their new tech to measure the blood pressure from 1,328 adult volunteers by comparing two-minute videos of their faces using an iPhone. The results were compared to standard blood pressure-taking devices and found that the transdermal optical imaging technology had an accuracy of 95 to 96%. The researchers stated that their technology could be used to provide health services to those with limited access to medical professionals in remote areas. They also plan to expand on the tech to measure other health markers, including cholesterol, blood glucose levels, and hemoglobin.