Nearly half of American adults have high blood pressure, and you may even not know about it.
Traditional cuff-based blood pressure measuring devices, although highly accurate, are not common enough to fulfill every family’s need due to its inconvenience and uncomfortableness.

However, a new method to monitor blood pressure has been invented and tested: a two-minute video using an iPhone equipped with transdermal optical imaging software can measure the blood pressure highly accurately.
The new video-selfie measurement
The software in smartphone detects blood flow changes in captured facial videos. Ambient light penetrates the skin’s outer layer allowing digital optical sensors in smartphones to visualize and extract blood flow patterns, which transdermal optical imaging models can use to predict blood pressure.
According to 1,328 tests in Canadian and Chinese adults by capturing two-minute videos, the results of measurement showed a high accuracy.

The researchers compared systolic, diastolic and pulse pressure measurements taken by smartphone videos and traditional cuff-based ways, and found that the systolic blood pressure measurements were nearly 95% accurate, and diastolic blood pressure and pulse pressure were nearly 96% accurate.
Systolic, diastolic and pulse pressure
We all know the heart never stops beating. When it beats, it pushes blood into your body through your arteries; between those beats, the blood comes back to your heart to be refreshed.
Systolic blood pressure means the pressure created by your heart squeezing and pushing blood to your blood vessels, which is the top of your blood pressure. Diastolic blood pressure is the pressure on your blood vessel when the hearts rests between beats, which is the bottom of the blood pressure numbers.
Pulse pressure refers to the difference between the systolic and diastolic blood pressure.

Categories of blood pressure level classification chart
Blood pressure category | Systolic mmHg | | Diastolic mmHg |
Normal blood pressure | <120 | And | <80 |
Elevated blood pressure | 120-129 | And | <80 |
Stage 1 high blood pressure | 130-139 | Or | 80-89 |
Stage 2 high blood pressure | ≥140 | Or | ≥ 90 |
High blood pressure is harmful to the body because it causes the heart to work harder than normal, leaving both the heart and arteries more prone to injury. It also increases the risk of heart attack, stroke, damage to the eyes, kidney failure, etc.
Wide application of the device
The technology of transdermal optical imaging has reached the international standard of accuracy for devices used to measure blood pressure.

However, since the experiments were done in a well-controlled environment with fixed lighting, it’s not clear how the device will perform in other environments like patients’ homes. Besides, current research is only partly proved to be effective on people with different skin tones.
Despite the uncertain factors remaining for the device, a more convenient service of taking blood pressure can be expected in the near future. At that time, you can just take your blood pressure with a simple enough video selfie.