How to Adjust CGM Alarm Thresholds for Better Sleep with Type 1 Diabetes
When did you last actually look at your CGM alarm threshold settings? Not to silence an alarm. Not to check a number. To actually look at the thresholds, the settings, the specific values, when they were last changed. If your answer is...
The episode, word for word
Four weeks ago, I asked you to do one thing.
Write down how many hours you slept. That was it. Just a number. Didn't have to be accurate. Didn't have to be impressive. Just a number.
Some of you have been writing down numbers every single day for four weeks. Some of you did it twice and then forgot about it. Some of you just found this challenge today and you're doing the thing where you scroll back through all the episodes in one afternoon like you're bingeing a show.
All of that is fine. You're not behind. Jump in right here.
My name is Neil Greathouse, and this is Your Best T1D Year.
All right. End of May. Month one of the While You Were Sleeping Challenge. Let me do what any decent coach does at halftime.
Pull everyone in. Take a breath. Go over what we actually know.
Because here's what I've noticed in my own life and what the research consistently shows in T1D populations: we spend a lot of time learning information that changes how we feel. And we don't spend enough time actually sitting with what changed.
So here's what changed. Or at least, here's what we covered.
Week 1 was about recognition. Naming the thing. You've had blood sugars you couldn't explain. You've been awake at 3am more nights than you can count. You've been blaming things that weren't the actual problem, the site, the insulin, the banana, the general vibe, LeBron flopping, whatever. And there was a variable on the board the whole time that nobody put on the checklist.
Week 2 was about the number. 21%. One bad night of sleep. Same insulin. Twenty-one percent less effective. And then we talked about the pancreas, which retired in 1992 without leaving a forwarding address and left all of us doing its job manually with a correction dose and a prayer.
Week 3 was about mechanisms. Your liver is running a 3am shift every single night, manufacturing glucose and releasing it into your bloodstream whether you know about it or not. The sleep-blood sugar relationship runs both directions and you can interrupt it from either end. And the most impactful sleep variable for T1D time in range isn't total hours, it's bedtime consistency.
I did not warn you about the hepatic glucose output. That's on me.
And then Episode 200, which was... I mean, two hundred episodes. I've done this more times than I've done a lot of things in my life, including laundry, which I could do more often. Thank you for that. Genuinely.
Here's the thing about this first month. It was all problem and mechanism. No solutions. I did that on purpose. Because I've found, in 34 years of managing this and talking to people who manage it, that solutions don't land until the problem is fully named. You can't fix something you haven't actually seen.
You've seen it now.
June is where we build. Pre-sleep routines, cortisol, fear of hypoglycemia, your CGM as a proactive tool instead of a reactive one, what "good enough" sleep actually looks like for someone managing a 24-hour disease. The whole second half.
We're going into it with something that's harder to quantify but more important than any single study: you've been paying attention. For four weeks, you've been looking at sleep differently. You've been running data. Even if you only wrote it down twice. Even if your bedtime was all over the map. You were watching.
That's the whole point.
What's one thing you've noticed in the last four weeks? Not a conclusion. Not a solved problem. Just a thing you've noticed.
Write it down. One sentence. Even if it's "I've been waking up tired every morning that followed a late night." Even if it's "I have no idea what I noticed, I just feel like I should sleep more."
That's data. We're using it in June.
Hey. If you made it through May, you did something real. Even if you don't feel like you did. Even if you didn't track every night or try every challenge. You spent four weeks paying attention to something you'd been ignoring.
That's not nothing. In T1D management, paying attention to a new variable is a meaningful act.
You're not doing a bad job. You're doing a difficult job with more information than you started with. And I'm proud of you.
See you in June.
Type 1 diabetes is relentless, but managing it doesn't have to be. New episodes every Monday, Wednesday, and Friday. You're not doing a bad job, you're doing a difficult job. Nobody remembers easy.
This is the script as read on the mic, lightly tidied for reading. Education, not medical advice. Talk to your care team before you change anything about your insulin.