The continuous glucose monitor 🔗
I got a diabetes diagnosis earlier this year. It wasn’t great to hear, but it was good to know: It helped me understand some things that were going on, and it prompted some lifestyle changes that helped me feel a lot better right away.
I asked my doctor if I needed to do regular blood sugar monitoring, and he was happy to prescribe a finger-stick meter.
There was a small disconnect on my care team: The nurse who showed me how to use it recommended readings four times a day. I did that for a few months between checkups, doing readings first thing in the morning, then two hours after each meal. It was interesting, but it didn’t feel useful. My numbers were pretty steady, with the occasional surprise if it turned out I’d eaten something with a lot of added sugar somewhere in the recipe. The meter could sync with an app (and hence Apple Health), so it was encouraging to at least see my averages creeping down after the initial big drop thanks to medication.
When I showed my numbers to my doctor and came back with a much lower A1C result, he said I could back off the four-times-a-day readings. That was welcome news, because it was a hard habit to keep up. Having ADHD, it made me anxious whenever anything threatened the routine, because it’s easy for me to lose a habit. He recommended instead doing morning readings a few times a week, which I’ve heard from other people. That was an even harder habit to maintain.
Thanks to a new job and new healthcare provider, I had a little bit of hangtime between physicians. I realized I wasn’t sticking to my measurements as closely as I should. Continuous glucose monitors (CGMs), which involve sticking a little smaller-than-an-AirTag tile on your arm and send measurements to your phone every five minutes seemed promising, but not easily prescribed.
I ended up dithering back and forth, and picked up my measurements with a little more diligence, and that told me that the lack of more constant feedback might be a problem: My average blood glucose levels seemed to have plateaued higher than I wanted.
So I went ahead and enrolled in Levels, which will sell you a CGM prescription in exchange for your data.
CMG sensors last for 10 days. It takes about two minutes to install one: Pop off the cover of a spring-loaded applicator, press it against the back of your arm, press a button, smooth down the adhesive, apply a second cover, and pair it with your phone. Then it just sits there taking readings.
The only habits I have to maintain with my CGM are:
- Recording exercise. The app can read from Apple Health, so my Garmin Instinct and Apple Watch both work with it.
- Recording sleep. I use the Sleep Cycle app to record sleep, which talks to Apple Health, which talks to the Levels app.
- Recording meals. The Levels app lets you just take a picture of your meal, which it timestamps.
It’s pretty low maintenance given the data I get back. There’s no real “data entry” unless I decide to go back and record what was in my meal to get little tips about their relative healthfulness for a diabetic.
Generally, though, I’ve been content to just observe and adjust thanks to the constant feedback. Given the continuous monitoring, I can see the impact of things I eat in ways I couldn’t when I was just doing finger sticks two hours after meals: Things that trigger spikes that come and go well inside that window.
In the 40 days or so I’ve had it, I’ve made a few adjustments that have both lowered my average blood glucose levels and seem to keep me more stable generally: Spikes last less time, there’s less variation during the day, and my waking blood glucose levels are dropping.
The experience has also impressed on me the amazing variability of human bodies. I was following a lot of generic advice that seemed okay because I couldn’t see what was happening between measurements. With closer measurement, I could see that some advice works very well for my body, and some just does not.
Drawbacks?
Well, it’s expensive. My insurance company doesn’t cover it, so I’m out of pocket on it. I can afford it and it’s worth it to me, but it is not affordable for a lot of people.
Sometimes communications between phone and sensor drop out, but that’s not a huge deal. The data is buffered, and if I notice that it’s happening I just toggle Bluetooth on and off and it re-pairs and catches the app up.
Sometimes the sticky mounting material doesn’t stay stuck and I have to get a large Band-Aid to put over it for showering or making sure it doesn’t snag on my sleeve.
In return, though, I get a huge amount of useful information that allows me to make better choices and better judge my tradeoffs because my blood glucose is generally lower and more stable. That makes the whole experience better because some things I’ve learned to forego make it easier to have things I wouldn’t have given a less stable, higher average.