I saw an Instagram story a few weeks back that intrigued me.
In it, a friend of mine was talking about how she “soaks” her CGM sensors. Instantly, I was confused: What the heck did she mean by that? Soaks them in what, hot water or some other liquid?

Within seconds, her definition of “soaking” became much clearer. “Soaking” a CGM sensor means inserting a fresh sensor hours before you intend to activate it. Rather than giving your sensor just two hours to warm-up, you’re giving it 4-6 hours so it can supposedly provide much more accurate readings immediately after the warm-up period has ended.
I was interested in this practice because I’ve definitely experienced sensors that were off for several hours post-insertion/warm-up. Sometimes, it even takes a full day for a sensor to start reporting accurate numbers, and I wouldn’t exactly call that efficient.
While I haven’t had the guts to actually try sensor soaking yet – I’d like to sometime in the near future – I’ve been doing some research on it so I’m fully prepared to try it whenever I’d like. Here are some questions I had about the process, and the answers I’ve found to them:
Q: Doesn’t this mean that you’re wearing two sensors at once?
A: Yes. But it’s only for a short window of time, until the old sensor expires and it’s time to activate the new one; in other words, for the full soaking period.
Q: How long should I let a new sensor soak?
A: According to what I’ve found online, it seems that 4 to 6 hours is the sweet spot for soaking. It’s basically doubling or tripling the built-in warm-up period that all sensors must go through, so I can see how this might contribute to improving immediate accuracy.
Q: How do I protect the new sensor if it doesn’t have a transmitter snapped in it for several hours?
A: The reason why I haven’t tried soaking yet is because I was worried about wearing a sensor that didn’t have a transmitter snapped in it. But I found some photos online of people who wore transmitter-less sensors with stretchy, self-adhesive wrap tape to protect the nook in which transmitters rest for the soaking period. It’s smart to protect that space, because in theory, it could be vulnerable to catching on clothing or other surfaces. Plus, tape like that is really easy to remove without damaging the sensor in the process.
Q: What changes about the sensor activation process when it’s finally time to start the new soaked sensor?
A: My research leads me to believe that nothing really changes at the end of the soaking period/when it’s time to activate the soaked sensor. All that will be needed is the sensor code so it can be properly activated within the receiver/Dexcom app. So the most important thing you can do at the very start of the soaking period is hold onto your sensor code/store it somewhere safe so you’ll be able to enter it at the end.
Q: So…why would anyone bother trying this again?
A: My understanding is that it all relates back to making sure a fresh sensor is as accurate as possible once it’s activated. I can’t tell you how many times I’ve put on a new sensor, only to discover a few hours after it has warmed up that it’s off by 40 or 50 points – and that just doesn’t cut it. So I don’t think there’s any harm in me giving sensor soaking a shot one of these days. I just have to remember to do it, and have the patience to wear three devices at once (my pod, the soon-to-expire sensor, and the new soaking sensor).
Have you tried soaking? If so, please drop a comment and let me know your thoughts on it – and be sure to tell me if I missed any key steps in my research!