Sibionics GS1

The Sibionics GS1 is a continuous glucose monitor (CGM) made by Shenzhen Sibionics. It does the basic job the category exists to do — a 14-day, factory-calibrated sensor (one-piece construction as described on this page, not in the fetched product wording) that sends a reading to your phone every five minutes, 288 times a day, with high and low alerts you can set yourself.³ What makes it worth a page here is not its technology but its geography: nearly every CGM on this site is a US or EU product, and for most people with type 1 diabetes on earth those sensors are either unavailable, unaffordable, or both. The GS1 is one of the sensors filling that gap.

We have tried to write this entry without either of the two easy failures: dismissing it because it isn't a Dexcom, or boosting it because the access story is sympathetic.

Accuracy — the honest version. An independent study published in the Journal of Diabetes Science and Technology in 2026 put the GS1 through a deliberately hard test: 116 hospitalized adults with diabetes, given a carbohydrate challenge, with 580 sensor readings matched against plasma glucose. The overall MARD (mean absolute relative difference — lower is better) was 11.83%, against the manufacturer's claim of 8.7–8.83%.¹³ All readings fell in the clinically acceptable zones of the DTS error grid (86% in zone A, 14% in zone B), so it is not a dangerous sensor — but 11.83% is a clear step behind the ~8.2% of the Dexcom G7 and the single-digit MARDs of the current Abbott sensors (comparator figures as given on this page, not in the sources read this pass).

Two caveats cut in opposite directions and you should hold both. First, that study was a hyperglycemic challenge in hospitalized patients with type 1 and type 2 diabetes — a harder setting than ordinary daily wear, which will push MARD up. Second, and more importantly: neither published study is an ambulatory type 1 accuracy trial. The other one, in Frontiers in Endocrinology, reported a much friendlier 8.01% fasting-phase MARD — but in 129 healthy volunteers during a glucose tolerance test, and with a Sibionics employee as a co-author.² Healthy people are an easy test. Neither number is measured the way Dexcom's and Abbott's headline MARDs are measured, so putting them side by side in a table — as our scorecard inevitably does — flatters nobody and should be read with that in mind.

Lag is its real weakness. The same 2026 study measured the delay between blood glucose and what the sensor reported. At steady state it was about 5 minutes, which is good. But during a rapid glucose rise the lag stretched to 10 minutes at 30 minutes and 20 minutes at 60 minutes.¹ If you are trying to catch a post-meal spike — the exact moment a CGM earns its keep — a sensor that is twenty minutes behind the truth is showing you the past. That is why we score its lag below the mainstream sensors rather than at parity.

It is a closed system. The GS1 drives no automated insulin delivery (AID) system, no pump, and no open-source loop; the manufacturer names none.³ Your data live in the SIBIONICS app. For someone whose ambition is a closed loop, this is close to disqualifying — it is a sensor for looking at your glucose, not for automating it. That single fact is the biggest reason it ranks where it ranks.

Ketones. None. Like every mainstream CGM, it senses glucose only, and cannot warn you about the ketones that precede diabetic ketoacidosis.

Regulatory access. The manufacturer’s newsroom confirms EU MDR CE certification for GS1 in 2023, and its European storefront lists it for sale. The earlier statement that no primary CE source could be found was incorrect. Minimum age is 3 in selected countries and 18 in others (age split as given in the cited locations directory, a GS3-era page, not a GS1-specific source); local indications and reimbursement still need checking.⁵

Who it's for. Someone who wants continuous glucose data, is not running an AID system or a loop, and for whom the alternative to this sensor is not a Dexcom — it is fingersticks, or nothing. Judged against that alternative rather than against a G7, an 11.83% MARD sensor on your arm for fourteen days is a large improvement in a life. Judged against a G7, it is not close. Both comparisons are legitimate; which one applies depends entirely on where you live.