It Doesn't Hurt at All! Placing the Sensor – What You Need to Know

If you want to keep a continuous eye on your blood sugar, there's no way around a small sensor. It's placed for you at the practice, so you're medically covered and get a proper onboarding from the start. Two established systems are used: the Dexcom G7 and the Freestyle Libre 3. Both are certified medical devices with reliable accuracy, but they differ in the details — the Dexcom can pair with Apple Health and the Apple Watch and lasts up to ten days, while the Libre 3 is worn only on the upper arm but lasts up to fourteen days and sits a bit more discreetly.

There's a good reason the sensor is placed professionally: every skin reacts differently, and not every phone is equally easy to set up. Being guided on-site ensures the device is optimally configured for the individual and that someone is immediately available in case of unexpected skin reactions. That very worry — that placing it might hurt — turns out to be unfounded in practice: most people find the process painless, at most noticing brief pressure or a barely perceptible pinch.

The sensors also hold up well in everyday life: both are waterproof and can be worn in the shower, while swimming, or even in the sea, with the Dexcom G7 tolerating slightly more depth and time than the Libre 3. Saunas call for caution, though, since temperatures above 40°C can shorten the sensor's lifespan. If a sensor does fall off before its wear time is up, a replacement is provided without any hassle — extra adhesive patches can help secure it better, especially in the first 24 hours.

Technically, neither system measures blood glucose directly; both measure sugar in tissue fluid, which is why small differences from a classic blood test are normal. The Dexcom G7 measures every five minutes and transmits automatically, while the Libre 3 measures every minute, with no manual scanning needed. Both communicate with the phone over Bluetooth at a range of around six meters and buffer data for eight to twenty-four hours if the connection drops. Studies on continuous glucose monitoring also suggest better blood sugar control and lower long-term values are possible — a benefit that goes well beyond pure convenience.