Germany Bans Smartwatches Faking Blood Glucose Measurement

Germany's Federal Network Agency has pulled the plug on smartwatches claiming to measure blood glucose without an external sensor. These devices, mostly cheap imports marketed aggressively online, were telling users their blood sugar levels using nothing but optical sensors on the wrist. That data was fabricated. No wrist-based optical sensor currently on the market can reliably read blood glucose through skin.

This matters because real continuous glucose monitoring requires either a subcutaneous sensor (like Abbott's Libre or Dexterity) or a validated electrochemical patch. The physics of measuring glucose transcutaneously with just light is an unsolved problem at consumer price points. Companies like Apple, Garmin, and Samsung have reportedly explored it for years and none have shipped it. There is a reason for that.

For endurance athletes, the appeal is obvious. Blood glucose tracking during long runs, bike rides, or Ironman-distance efforts would be genuinely useful data. Knowing when you are bonking before you bonk is the dream. But fake readings are worse than no readings. An athlete fueling off bad glucose data during a 100-mile ultra or a long triathlon could make decisions that hurt performance or health.

The scam devices were largely sold through Amazon and AliExpress, priced between 30 and 80 euros, and carried impressive-sounding spec sheets. Some mimicked the visual language of legitimate medical wearables. The German regulator acted after consumer complaints and independent lab testing confirmed the glucose readings bore no correlation to actual blood sugar levels.

Buy a Garmin Fenix 7, a Polar Vantage V3, or a Coros Vertix 2S if you want serious endurance metrics. Skip any watch under 150 euros promising non-invasive glucose. The tech does not exist yet at that price. Full stop.