Samsung skin sensor can detect calorie intake

New patent could usher new wearable tech era
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Samsung is working on a wearable skin sensor that can estimate your calorie intake – according to an updated payment.

The Galaxy Watch-maker appears to be edging closer to perfecting skin sensors that would automatically track the caloric value of your food and drink intake – no manual input required. 

While much of the wearables industry – including Apple and Huawei – are grappling with non-invasive blood glucose tracking aimed at the pre-diabetic population, Samsung seems to be focused on establishing a broader use case. 

In a recently updated patent, Samsung outlines a skin spectrum measurer (spectroscope) that would “radiate light onto the skin of the user and detect spectral lines of the light that returns from the skin.”

Samsung explains the feature would take an initial wavelength reading detecting the glucose currently absorbed into the blood when the wearer has an empty stomach. Secondary readings would be made after eating or drinking. The algorithm can work backwards to estimate the total glucose absorbed into the blood, and hence the caloric intake.

The description reads: “After a user has had the food and drink… a subtle change in a spectrum of the skin is generated. When 75 g of glucose is ingested the normal calories are 227.5 kcal.” 

The flow diagram accompanying the patent simplifies matters somewhat: Start > Measure user’s skin spectrum > Calculate noise of measured spectrum > Estimate user’s calories based on calculated noise > End.

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All data would be transmitted to a companion app where users could monitor their calorie intake over time and spot trends, without the annoying need to input meals and log food.

The attached diagrams show the tech embodied within a smartwatch, meaning this tech could be primed for a future Galaxy Watch. 

Smartwatches have long estimated how many calories have been burned through motion and heart rate data. However, integration of the tech described in this patent could provide a holistic picture of the calorie surplus or deficit on any given day. 

Right now, there are some devices that can already accomplish this feat, albeit in different ways. The HealBe GoBe 3, for example, uses bioimpedance sensor data and a patented Flow technology. 

The company explains its device measures fluid moving in and out of your cells caused by the changes to glucose levels. As well as calories, the makers claim the device can accurately log consumption of carbs, fats, and proteins because each nutrient category is absorbed at different rates. 

In the mainstream wearable realm, it looks like Samsung will be beaten to the blood glucose tracking feature by rival firm Huawei. In mid-May 2023, Huawei announced it is trialing blood glucose tracking on the new Huawei Watch 4, but only in China.

However, in this instance, the feature isn’t necessarily designed to track calorie intake, but as a non-invasive, no-needles way to assess the risk of high blood sugar for diabetics.

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"Huawei Watches will be the first to support high blood sugar risk assessment research., Everyone authorizes to join the research project and after wearing the watch for a period of time, the watch will notify of high blood sugar,” Huawei said in announcing the trials. 

Apple is also closing in on this ‘holy grail’ feature for the Apple Watch range, according to a recent report. 

While speculation has long tipped a blood sugar sensor for the smartwatch, the company “now believes it could eventually bring glucose monitoring to the market.”

In February, Bloomberg’s Mark Gurman reported Apple hit a major milestone with optical absorption spectroscopy technology that could lead to inclusion sooner rather than later. 

Movano is also working on an RF sensor that could live inside a smart ring, with blood glucose trials also scheduled to commence this year. 

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Chris Smith


Chris has more than decade of experience writing for the UK's foremost technology publications including TechRadar, T3 and more.

 A freelance journalist based near Miami, Florida, Chris has written for Wareable since its inception in 2014. From reviews of the latest fitness devices, and in-depth features on bleeding-edge wearable devices, to future-gazing interviews with some of the industry's brightest minds, Chris covers the lot. He also writes about sport for The Guardian and is the author of many technology guide books, while also dabbling in film, music, beer, travel and political commentary.

When he's isn't smashing away at the keys of his MacBook, Chris can be found at his favourite craft breweries, dangling his rod in the warm waters of the Florida Keys, or exploring the Shropshire countryside.

You can follow his on Twitter but beware, it's mostly sporting and political hot takes, occasionally interspersed with tech-based tweets.

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