The Dawn Phenomenon in Type 1 Diabetes: Why Your Blood Sugar Rises While You Sleep

Cortisol and Blood Sugar: The T1D Overnight Connection You're Probably Missing

SHOW NOTES: Cortisol isn't trying to ruin your blood sugar. It's trying to help. It has never once, in your entire life, acted with malice. It is a useful, important hormone that is -- in the modern world -- very confused about what an actual emergency looks like. This episode is about cortisol: what it's designed to do, what it's actually responding to in modern life ("quick question" emails at 10pm), and what it's doing to your blood sugar by midnight. For T1D people, cortisol-driven blood sugar rises don't get quietly compensated by a functioning pancreas. They land. And they land on top of whatever else was already happening overnight. Understanding the cortisol loop is the first step to interrupting it -- starting with the hour before bed. We're in Week 6 of the While You Were Sleeping Challenge. Solutions are building. In this episode: * What cortisol is actually designed to do -- and why your lion never shows up * How cortisol raises blood sugar in T1D without the automatic pancreas feedback to catch it * The full cortisol loop: poor sleep raises cortisol, cortisol raises blood sugar, elevated blood sugar disrupts sleep * Why what you do in the hour before bed shows up in your midnight glucose * How to start rating your pre-bed stress and looking for the pattern in your own data This Week's Challenge: Rate your stress level 1-10 before bed, three nights this week. Note your morning blood sugar each time. Look for the pattern. Helpful resources and newsletter: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Connect with Neil: TikTok: https://tiktok.com/@the.betes [https://tiktok.com/@the.betes] Instagram: https://instagram.com/thebetes [https://instagram.com/thebetes] Facebook: https://facebook.com/neilgreathouse [https://facebook.com/neilgreathouse] LinkedIn: https://linkedin.com/in/neil-greathouse-a607b912 [https://linkedin.com/in/neil-greathouse-a607b912] Website: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Books on Amazon: Type 1 Diabetes – One Day at a Time: https://a.co/d/6UHooWJ [https://a.co/d/6UHooWJ] Type 1 Diabetes – True Stories: https://a.co/d/dfIlyI1 [https://a.co/d/dfIlyI1]

How Bedroom Temperature and Blue Light Affect Blood Sugar in Type 1 Diabetes

SHOW NOTES: Neil wants to be upfront: this episode is going to sound like wellness content delivered by someone standing in a field in linen pants. He knows. He can't control how it sounds. What he can tell you is that there's actual research behind all of it, it specifically applies to T1D glucose management, and he read most of it at midnight on his phone in bed with the screen at full brightness. Your sleep environment -- specifically temperature, light, and screen exposure -- directly affects the hormones that regulate both sleep and glucose. For T1D people, those hormones matter more because there's no backup system to compensate when they go sideways. Blue light at 10pm tells your brain it's daytime, suppresses melatonin, and raises cortisol. A warm room keeps your core temperature elevated, making it harder to drop into deep sleep. Both of these things are doing quiet work against your blood sugar while you're trying to rest. We're in Week 5 of the While You Were Sleeping Challenge. In this episode: * How blue light from screens suppresses melatonin and triggers cortisol at 10pm * Why your phone screen registers as "daytime" to your brain's sleep-wake system * Core body temperature and its role in reaching deep sleep stages * The research-backed temperature range for better sleep quality * One practical environmental change to make tonight that doesn't require buying anything This Week's Challenge: Know your bedroom temperature. Tonight, put your phone face down one hour before bed. Not in another room -- just face down. See what happens. Helpful resources and newsletter: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Connect with Neil: TikTok: https://tiktok.com/@the.betes [https://tiktok.com/@the.betes] Instagram: https://instagram.com/thebetes [https://instagram.com/thebetes] Facebook: https://facebook.com/neilgreathouse [https://facebook.com/neilgreathouse] LinkedIn: https://linkedin.com/in/neil-greathouse-a607b912 [https://linkedin.com/in/neil-greathouse-a607b912] Website: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Books on Amazon: Type 1 Diabetes – One Day at a Time: https://a.co/d/6UHooWJ [https://a.co/d/6UHooWJ] Type 1 Diabetes – True Stories: https://a.co/d/dfIlyI1 [https://a.co/d/dfIlyI1]

Your Pre-Sleep Blood Sugar Check Is a Sleep Decision, Not Just a Safety Check

SHOW NOTES: You already do this. You check your blood sugar before bed, glance at your CGM, maybe set a temp basal. You've been doing it for as long as you've had T1D. Here's the reframe: you've been doing it as a safety check. "Am I okay to go to sleep?" This episode argues it's also a sleep decision -- and that shift changes what you're actually optimizing for. Active insulin at midnight is a sleep variable. A correction dose from 9pm is still tailing off at 1am. That tail can create glucose variability that pulls you out of deep sleep without triggering an alarm -- a partial arousal that costs you sleep quality without you knowing it happened. The more stable your blood sugar heading into sleep, the fewer overnight alarms, the better your sleep architecture, and the better your insulin sensitivity the next morning. Welcome to June. Welcome to Week 5 of the While You Were Sleeping Challenge. This is where we start doing something about it. In this episode: * How pre-sleep blood sugar affects sleep quality, not just overnight safety * What active insulin at bedtime does to your 1am and 2am sleep stages * The 30-minutes-before-bed check and why timing makes a difference * How pre-sleep glucose stability connects directly to tomorrow morning's insulin sensitivity * Starting the feedback loop running in the right direction tonight This Week's Challenge: Check your blood sugar 30 minutes before bed -- not right when you're about to sleep. Note the number and any active insulin on board. Do this three nights and see what the mornings look like. Helpful resources and newsletter: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Connect with Neil: TikTok: https://tiktok.com/@the.betes [https://tiktok.com/@the.betes] Instagram: https://instagram.com/thebetes [https://instagram.com/thebetes] Facebook: https://facebook.com/neilgreathouse [https://facebook.com/neilgreathouse] LinkedIn: https://linkedin.com/in/neil-greathouse-a607b912 [https://linkedin.com/in/neil-greathouse-a607b912] Website: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Books on Amazon: Type 1 Diabetes – One Day at a Time: https://a.co/d/6UHooWJ [https://a.co/d/6UHooWJ] Type 1 Diabetes – True Stories: https://a.co/d/dfIlyI1 [https://a.co/d/dfIlyI1]

T1D Sleep Challenge: Four Weeks In, What We've Learned

SHOW NOTES: Four weeks ago, Neil asked you to do one thing: write down how many hours you slept. That was it. Just a number. And now here we are. This is the halftime checkpoint of the While You Were Sleeping Challenge. Neil does what any good coach does at halftime -- pulls everyone in, takes a breath, and goes over what we actually know. Because the first four weeks covered a lot: recognition, the 21% number, the dawn phenomenon, the sleep-blood sugar feedback loop, bedtime consistency, sleep architecture differences in T1D, and CGM alarm fatigue. And the goal today is to actually sit with what changed before we move into solutions. May was all problem and mechanism. June is different. June is where we build. We're in Week 5 of the While You Were Sleeping Challenge. If you're just finding this, jump in right here. You're not behind. In this episode: * A full recap of Weeks 1 through 4 and everything established so far * Why problem-naming has to come before solution-building * What the second half of the challenge covers (cortisol, Fear of Hypoglycemia, CGM as a proactive tool, pre-sleep routines) * How to look at your own four weeks of data before June begins * What "paying attention" for four weeks actually produced, even if the tracking wasn't perfect This Week's Challenge: What's one thing you noticed in the last four weeks? Not a conclusion. Not a solved problem. One thing you noticed. Write it in one sentence. Helpful resources and newsletter: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Connect with Neil: TikTok: https://tiktok.com/@the.betes [https://tiktok.com/@the.betes] Instagram: https://instagram.com/thebetes [https://instagram.com/thebetes] Facebook: https://facebook.com/neilgreathouse [https://facebook.com/neilgreathouse] LinkedIn: https://linkedin.com/in/neil-greathouse-a607b912 [https://linkedin.com/in/neil-greathouse-a607b912] Website: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Books on Amazon: Type 1 Diabetes – One Day at a Time: https://a.co/d/6UHooWJ [https://a.co/d/6UHooWJ] Type 1 Diabetes – True Stories: https://a.co/d/dfIlyI1 [https://a.co/d/dfIlyI1]

How to Adjust CGM Alarm Thresholds for Better Sleep with Type 1 Diabetes

SHOW NOTES: 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 "when I first set up the device," this episode is for you. Neil walks through what CGM alarm thresholds are, why they're not permanent features of having T1D, and why the settings you're running right now may be calibrated for a different version of your management than the one you have today. Your diabetes has changed. Your time in range has changed. Your thresholds probably haven't. This is a practical episode -- no heavy science, just a straightforward conversation about settings you can actually look at and, when appropriate, adjust. We're in Week 4 of the While You Were Sleeping Challenge. This is the actionable follow-up to Monday's alarm fatigue episode. In this episode: * What CGM alarm thresholds are and how most people originally set them * Why outdated thresholds create unnecessary overnight wake-ups even when management has improved * The difference between thresholds optimized for daytime control vs. overnight sleep * Quiet hours and do-not-disturb settings most CGM users don't know exist * Why this conversation is worth having with your care team This Week's Challenge: Open your CGM app. Find the alarm threshold settings. Look at the numbers. Do they still match where your management actually is? Helpful resources and newsletter: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Connect with Neil: TikTok: https://tiktok.com/@the.betes [https://tiktok.com/@the.betes] Instagram: https://instagram.com/thebetes [https://instagram.com/thebetes] Facebook: https://facebook.com/neilgreathouse [https://facebook.com/neilgreathouse] LinkedIn: https://linkedin.com/in/neil-greathouse-a607b912 [https://linkedin.com/in/neil-greathouse-a607b912] Website: https://yourbestt1dyear.com [https://yourbestt1dyear.com] Books on Amazon: Type 1 Diabetes – One Day at a Time: https://a.co/d/6UHooWJ [https://a.co/d/6UHooWJ] Type 1 Diabetes – True Stories: https://a.co/d/dfIlyI1 [https://a.co/d/dfIlyI1]