Filming a selfie video may soon not just be a route to Instagram likes and TikTok shares, it could also check your blood pressure.

Using a front-facing iPhone camera equipped with special imaging software, researchers were able to detect blood flow patterns of 1,328 people by tracking subtle changes in ambient lighting as it reflected off the skin.

Systolic, diastolic and pulse pressure measurements captured from the two-minute clips were compared with blood pressure readings taken using more traditional devices, and they stacked up favourably.

Image: The technique compared favourably to existing blood pressure test methods

On average, systolic blood pressure was predicted with nearly 95% accuracy, while diastolic blood pressure and pulse pressure were at almost 96% - both within international standards for existing methods.

Everyone who took part in the study had normal blood pressure, and there was a variety of skin tones, but the footage was all recorded in a controlled setting with fixed lighting and it is unclear how well the technology would currently work in other environments, such as homes.


But lead author Kang Lee, a professor in developmental neuroscience at the University of Toronto, said the findings were still a major breakthrough.

Professor Lee said: "If future studies confirm our results and show this method can be used to measure blood pressures that are clinically high or low, we will have the option of a contactless and non-invasive method to monitor blood pressures conveniently - perhaps anytime and anywhere - for health management purposes."

The professor and his team are hoping to further test the technology by using more subjects with extremely dark or fair skin tones, and they are also looking into reducing the required video length from two minutes to 30 seconds.

Image: The British Heart Foundation said the new test could be a 'game-changer'

It could have a major impact if successfully introduced in the UK, with more than 14 million people living with high blood pressure according to the British Heart Foundation.

More than a third are said to be undiagnosed, making the condition a "silent killer".

Professor Metin Avikiran, associate medical director at the charity, told Sky News: "This innovative research is a powerful example of how data from mobile technology can be harnessed and analysed by modern machine learning methods to potentially transform cardiovascular care.

"If further research can confirm that this new approach works in people with very different skin tones, a range of blood pressures and in standard living environments rather than controlled laboratory conditions, then it could be a game-changer in helping doctors diagnose and treat high blood pressure more effectively."