Have you ever had a day where you didn’t eat anything unusual, but your blood sugar acted like you’d had a slice of cake for breakfast?
That happened to me more than once before I understood why. I’d look at my numbers and think, I haven’t even eaten yet — what is going on? Turns out, food isn’t the only thing my body reacts to. Stress does something to my blood sugar too, and once I saw it on my continuous glucose monitor (CGM), I couldn’t unsee it.
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Why stress raises blood sugar in the first place
Your body doesn’t know the difference between a deadline at work and an actual emergency. Stress is stress, as far as your nervous system is concerned.
When something stressful comes up, your body releases cortisol. Cortisol’s job is to get fuel into your bloodstream fast, in case you need to fight or run. It does this partly by signaling your liver to release stored glucose, and partly by making your cells less responsive to insulin for a little while — so that sugar stays available in your blood instead of getting absorbed right away.
For a short burst of stress, that’s actually a smart system. Your body is just trying to help you. The problem is, most of my stress isn’t a short burst. It’s ongoing — work, deadlines, my own expectations of myself, and just keeping up with everything going on in the world right now. When stress sticks around, cortisol sticks around with it, and blood sugar can stay elevated longer than it should.
If you want the basics on how blood sugar and insulin work together more generally, I covered that here.
What this actually looked like for me
I’m a planner. I like things buttoned up, and when they’re not, I feel it. Work stress is usually my biggest trigger — a packed calendar, a project that’s not going the way I wanted, that low hum of needing to be on top of everything.
The first time I noticed it on my CGM, I’d had a rough morning. Tense email, tight deadline, the whole thing. I hadn’t eaten a bite, and my glucose was already climbing. No food on board. Just stress doing its thing.
It wasn’t dramatic, but it was enough to make me pay attention. Once I started watching for it, I noticed it again and again — high-pressure mornings, restless nights worrying about something out of my control, even just doom-scrolling the news for too long. My body was responding to all of it, whether or not anything had touched my plate.
It’s not just the big stuff
This is the part I think people miss. You don’t need a crisis for this to show up. Low-grade, everyday stress counts too.
Rushing out the door. A long line that’s making you late. An argument that’s still bothering you three hours later. None of those feel like “real” stress in the moment, but your body doesn’t really grade on a curve. It responds to the pressure either way.
For me, the constant churn of bad news has been one of the sneakier ones. I care about what’s happening in the world, and I’m not going to pretend I can just turn that off. But I’ve had to notice that carrying it around all day has a cost, and my CGM has shown me that cost in a way I couldn’t really argue with.
What’s actually helped me bring it down
I’m not going to pretend I’ve solved stress. Nobody has. But a few things have made a real difference in how my body handles it.
Prayer is the first one. It’s where I land when things feel like too much, and it’s done more for me than almost anything else on this list. I won’t pretend it’s a CGM hack — it’s just true for me, and it’s part of how I get through the day.
Movement helps too, even something as simple as a short walk. I’ve written before about what a 10-minute walk after meals does for blood sugar, and the same idea applies here — moving your body seems to help burn off some of that stress response, not just the food response.
Sleep matters more than I gave it credit for. A bad night makes the next day’s stress hit harder, and I went deeper into that connection in this post on sleep and blood sugar.
Just knowing this connection exists has helped. When I see a number climb on a stressful morning, I don’t panic the way I used to. I know what’s behind it now. That alone has taken some of the edge off.
Why this matters if you’re trying to lose weight
If you’re stuck on a plateau and doing everything “right” with food, stress might be a piece you haven’t considered. Elevated blood sugar from stress alone won’t necessarily show up as a dramatic spike, but if it’s happening day after day, it adds up.
This is exactly the kind of thing a continuous glucose monitor (CGM) is good for catching. You can’t see cortisol. You can’t see your nervous system deciding today is a fight-or-flight kind of day. But you can see what your blood sugar is doing in response, and that’s information food logs alone will never give you.
Stelo is the CGM I’ve been using, and it’s available over the counter — no prescription needed. Watching how my numbers move on a stressful day versus a calm one has taught me more about my own body than I expected.
My takeaway
Stress isn’t just something you feel. It’s something your body actually does something with, and for a lot of us, that includes our blood sugar. I went a long time not realizing how much my own stress — the work pressure, the perfectionism, the heaviness of everything going on around us — was showing up in my numbers.
You can’t eliminate stress completely, and I’m not going to pretend otherwise. But understanding what it’s doing in your body is a different kind of power. It turns something invisible into something you can actually work with.
Have you ever noticed your blood sugar or your weight responding to a stressful season, even when your eating didn’t change much? I’d really love to hear about it in the comments.