Key wearable tech feature could pose health risk 

Experts warn bioimpedance sensors could affect pacemakers
Wareable Samsung bioactive feature
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The use of wearable body composition found on leading wearables could pose a risk for those with pacemakers, a new report has concluded.

A study in the Heart Rhythm journal found that wearables with bioimpedance sensing interfered with the proper functioning of some implanted cardiac devices from three leading manufacturers.

Bioimpedance sensors use a tiny electrical current that is passed around the body to measure fat mass, muscle density, and even water composition.

It’s a feature that we’ve seen on the Samsung Galaxy Watch 5 and Xiaomi Watch S2, which has launched in China. Going back in time, we saw it used on TomTom fitness trackers, and it’s widely featured on Withings smart scales.

“Bioimpedance sensing generated an electrical interference that exceeded Food and Drug Administration-accepted guidelines and interfered with proper CIED functioning,” said the lead researcher, Dr Benjamin Sanchez Terrones, of the University of Utah, as reported in The Guardian.

Interestingly, the study found that smartwatches and wrist-worn wearables seemed to pose a higher risk than scales and smart rings.

“The level of interference generated with smart scale and smart rings simulations was lower than with smartwatches,” the report read.

The study found that some implementations of bioimpedance sensors exceeded the FDA-recognized thresholds of leading pacemakers. And the result could “have the theoretical ‘potential’ to interfere, with undesirably disastrous consequences.”

While the risk appears low, the paper concluded that interference from wearables could result in “withholding lifesaving pacing in a pacer-dependent patient.”

The researchers have called for more research to be done to study the risk of bioimpedance to those who use pacemakers.

Samsung already posts a warning in the small print not to use its BioActive bioimpedance composition feature “if you have an implanted cardiac pacemaker, defibrillator or other electronic medical devices are inside of your body.”

It also advises against use for pregnant women.

But it might need to make these warnings more obvious to users with pace makers until more research can be conducted.

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James Stables


James is the co-founder of Wareable, and he has been a technology journalist for 15 years.

He started his career at Future Publishing, James became the features editor of T3 Magazine and and was a regular contributor to TechRadar – before leaving Future Publishing to found Wareable in 2014.

James has been at the helm of Wareable since 2014 and has become one of the leading experts in wearable technologies globally. He has reviewed, tested, and covered pretty much every wearable on the market, and is passionate about the evolving industry, and wearables helping people achieve healthier and happier lives.

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