Ep. 12: How sleep, stress and sickness can impact your blood glucose levels

If you've ever done everything "right" - eaten the right foods, timed your meals carefully, followed all the advice - and still gotten a number that made your stomach drop, this episode is for you.

There are so many things beyond what's on your plate that can quietly push your blood glucose levels around, and most of us just don't know about them. Poor sleep, a stressful week, a cold that won't quit - they can all shift your readings in ways that have absolutely nothing to do with a bowl of pasta or a piece of fruit.

In this episode I'm joined by Elise Hoyer, a diabetes educator and exercise physiologist, who works with women navigating exactly this stuff every day. We get into the real, hormonal reasons why your numbers can look completely different even when you're showing up exactly the same - and why that is not a reflection of you doing something wrong.

Honestly, this one is a reminder that you are so much more than a number on a meter. And that there's a lot going on in your body right now that deserves a bit more credit - and a lot more compassion.

What you’ll hear in this episode:

• Why poor sleep can raise your blood glucose levels through cortisol and its effect on hunger hormones - and what leptin has to do with it
• Simple sleep hygiene habits that can actually make a difference, even in the third trimester
• How to minimise those middle-of-the-night toilet trips by timing your water intake earlier in the day
• Why stress - including the non-obvious, low-level kind like remembering appointments and running the family - can shift your numbers
• How GDM itself can become a significant stressor, and practical ways to reframe your relationship with your readings
• What illness does to your blood glucose levels and why your body simply has other priorities when it's fighting an infection
• When it's worth getting in touch with your healthcare team if you're unwell during pregnancy
• Whether vaccinations like the whooping cough or flu shot can temporarily affect your levels
• What a "rage check" is, why it doesn't help, and what normal variation between readings actually looks like
• The reminder every woman with GDM needs to hear - your numbers do not define you

Resources & links mentioned:

• Smiling Mind → free mindfulness and meditation app, great for winding down before bed: https://www.smilingmind.com.au/
• Headspace → guided meditation app with free content available: https://www.headspace.com/

About the guest

Elise Hoyer is an Australian based diabetes educator and exercise physiologist who works with women managing gestational diabetes. 

Transcript

This transcript was auto-generated and lightly edited for clarity.

Celia (00:00) Today's conversation is for anyone who's ever looked at their numbers and thought, what did I do wrong? Because sometimes it's not just about what you ate. We're going to explore some of the hidden factors that can influence your blood sugar levels, and why these can make your readings look different even when you're still showing up with what's on your plate. I'm joined by Elise Hoyer, a diabetes educator and exercise physiologist. Elise, thanks so much for being here.

Elise (00:25) Thanks for having me, excited to be here.

Celia (00:27) So what are the most common things that come up when women report that their numbers are off, even if it looks like they're doing all the right things?

Elise (00:36) Honestly, that's what I have to keep telling the women that come through our doors - that you're doing everything right, you're eating everything like a textbook, but there's so many different things that people just don't realise can affect their glucose levels. Sleep is obviously a big one, and I'm sure you can relate - when you're pregnant, the sleep quality is not always there.

Celia (00:54) Thank you.

Elise (00:58) But even things like illness, and if they've already got other toddlers or children that might be sick as well - just that general mum life stress - which can all play a part. They can eat the same thing, but their glucose level is one or two millimoles different.

Celia (01:14) As you mentioned, broken sleep is just sort of a normal part of pregnancy. So maybe we'll jump right into that, because I am living that very much right now. What does a good night's sleep actually do for us with our blood sugar levels?

Elise (01:30) If you're that unicorn, kudos to you. My Garmin is always telling me I had a poor night's sleep, and I keep telling my Garmin that it clearly doesn't have children. So rude.

Celia (01:38) Rude. Yeah.

Elise (01:42) I can't really comment on the benefits for women that sleep well, but we do know that for women that have poor sleep quality or poor sleep hygiene, their glucose can be significantly disrupted. There are a few different reasons for that. One is cortisol - when you don't sleep enough, you get an increase in cortisol, the stress hormone. That naturally raises your glucose levels. But it also decreases the amount of a hormone called leptin, which is the hormone that makes your body feel fuller for longer when you're eating. Leptin is naturally released when you chew your food - so if you eat really quickly, it doesn't release as fast. But if you chew properly, leptin kicks in and tells your body, hey, I'm eating, I don't need as much. When you don't get enough sleep, your leptin doesn't release as well, so people feel hungrier. For women with gestational diabetes, they might find they're a bit more snacky, or possibly reaching for things that might impact their glucose levels. So those are probably the two biggest impacts - the cortisol, and then the leptin if they happen to be up and snacking more.

Celia (02:45) That's very interesting. I didn't know about leptin until now.

Celia (02:51) Are there any simple things we can do to help set ourselves up for a better night's sleep and possibly avoid triggering these hormonal responses?

Elise (03:00) Sometimes we find that a sleep routine - that preparation before you go to bed - can actually play a part in the quality of your sleep too. Trying to avoid screen time and turning that off an hour before bed, either reading a book or having a good skincare or shower routine, making sure the temperature is right and that you're comfortable. When you're pregnant, tossing and turning and changing sides can be really challenging, but it's amazing that if you can get that right, the sleep you actually have is better. So you tend to wake up feeling refreshed rather than feeling like you just need another ten hours. The preparation can make a big impact.

Celia (03:34) Yeah.

Elise (03:36) And then of course, if you're waking up to go to the toilet, we can talk about some strategies to try and get all your wees out before bedtime - this sounds ridiculous, but it really does help to minimise how many times you wake up.

Celia (03:45) That doesn't sound irrelevant to me right now at all.

Elise (03:51) We usually say try to have most of your water before 4pm. And look, if you're thirsty, have a drink. But if you get the bulk of it in before 4pm, it does tend to make a difference - you might only wake up once instead of three or four times. So yeah, have the water earlier. And I don't know about you, but my mind doesn't switch off. Sometimes I look at my husband and he's just staring blankly and I ask what he's thinking about, and he says honestly, nothing. How do men switch off their brains? I don't understand it. There are some really great free apps I've used personally during a particularly stressful time that kind of shut my brain down for a bit and help me focus on sleep. Smiling Mind is one I've used and recommend to women who are having trouble falling asleep because their mind is racing. They take you through different routines - maybe five or ten minutes of a mindfulness activity. I find it really hard to meditate on my own, but if I have a guided meditation where I'm listening to someone talking, I can focus on that voice rather than letting my brain go wild. That can really help promote better sleep quality.

Celia (05:00) Yeah, awesome. I'll pop a link to that in the show notes. Headspace is one I've used too - I know they've got a bunch of free content included.

Elise (05:08) Yes, definitely.

Celia (05:09) That's a good reminder. I definitely could do some work on my sleep hygiene.

Elise (05:15) The old doom scroll gets a lot of us. You scroll for five more minutes and then you look at the clock and it's been half an hour.

Celia (05:17) Yes, it does.

Celia (05:21) Yeah, I think it's tough, particularly if you're a parent. At the end of the day you're like, I'm just going to catch up with my friends and see the silly reels we've all sent each other - that ten minutes to yourself is precious.

Elise (05:30) Because you might not be able to check your phone during the day, and then the algorithm just takes you deeper into more funny reels and the hours have gone past. It's hard. We've actually got an alarm on our phone that goes off to remind us - hey, it's 8:45, time to put the technology away.

Celia (05:50) Yeah, you've got to draw the line somewhere.

Elise (06:02) And sometimes we ignore it, but it's that little gentle reminder to say, hey, it's time to put the technology away and pack up the kitchen. Yeah.

Celia (06:14) That's a great idea. We might jump into stress then - yay. Because since reflecting on my last pregnancy, when I had gestational diabetes, I didn't fully understand the relationship between cortisol and blood sugar levels.

Elise (06:20) Yay, stress!

Celia (06:34) Looking back now, I was renovating - well, my husband was doing most of the renovating, I was just picking things out, but it's still stressful. And still working full time.

Elise (06:38) Still stressful, my goodness.

Celia (06:49) I think I worked till maybe 35 weeks, full time across crazy time zones. There was a lot going on and I was just like, yeah, I can do this. Looking back now I'm like, I don't think I really clocked how much that was probably impacting me. No wonder I had insane fasting levels. So, you mentioned cortisol - that's the stress hormone. What does that actually do to our blood sugar levels?

Elise (07:21) It increases inflammation, and it's kind of like a fight or flight response. Your heart rate can go higher, your breathing rate can go higher, and your glucose goes up because your body is like, I need to work harder here. It's really hard to just say "don't stress" when you clearly are stressed. They say that moving house and renovating is one of the most stressful things you can do - let alone while pregnant. Hats off to you. Stress is a huge thing. And even when women come through our clinic, particularly if they're a real numbers kind of person, gestational diabetes can really get you. The amount of energy and work that women have to put in to monitor their glucose, to take care of themselves, their baby, their toddlers, their families - and on top of all of that, physically monitoring your glucose, whether through finger prick or CGM, that's a lot of data to take in. For some women - and I'm lucky that working in a private hospital the obstetricians are quite realistic about this - if someone's checking four times a day but getting really anxious every time they do a finger prick, that's when we take a step back and say, okay, let's look at which areas we really need to keep an eye on, and maybe do two tests a day instead. Kudos to all the mums out there that are testing, because it is hard work.

Celia (08:47) Yeah, it feels like this added job on top of everything else. And I think especially with the timing of when you get diagnosed - you're like, oh great, it's getting close to the final stretch and I can start preparing the nursery and relaxing. And instead it's like, actually, here you go.

Elise (08:50) Yep. On top of everything.

Elise (09:05) And it's also Easter, so here's the most sugary holiday of the year. Or Christmas. Or your birthday. Life doesn't stop. I think it's important to remember that those numbers don't define you. If a number comes up that's not at the level your healthcare provider has said, that's okay. You're not a bad person. There's lots we can do about it, but particularly when you're pregnant and your hormones are already heightened, it can make you feel really rubbish when you get a number that's not right.

Celia (09:36) And this is the irony - GDM itself becomes a pretty major stressor on top of life. Do you have any suggestions for ways to reframe things? Because you can't necessarily control what your numbers are going to be. How do you manage your outlook when you're juggling all of this?

Elise (09:55) I think it's important to have a really good relationship with your healthcare practitioner if it's worrying you. We're lucky in that we have the capacity to email our women each week and check in - and if they're not coping, we can put practical strategies in place. Like we mentioned, maybe reducing the number of finger pricks, or getting a partner to take the reading so the woman isn't physically seeing the number, but it's still being recorded. Having people around you who support you, or other mums who've been through it - though that can be a bit hit or miss, and some people don't love the group setting. But having your immediate support people around you is important. And remember, they're just numbers. They're not defining you. It's also always nice to hear that it's not your fault, because gestational diabetes isn't your fault - but it's important to hear that regularly to remind yourself that this is just the placental hormones. And let's be honest - the males are in charge of making the placenta. So if you want to blame someone, blame them.

Celia (10:55) I have recently heard that. I really want to get someone deep in the science to come on and confirm it so we can share that around.

Elise (11:03) The obstetricians tell us it checks out, so we tell all our women - it's your partner's fault. If you want to blame someone, blame them.

Celia (11:14) That already makes me feel a little bit more relaxed.

Elise (11:18) Good. They're the ones who control the placental hormones. You can't control them.

Celia (11:23) I was actually just reading yesterday in one of those support groups - which I can completely vouch for, yes, sometimes it's great, sometimes you get hit with too much info and a thousand personal anecdotes. A woman was sharing that she'd had children with her first husband and then two with her second, and she'd had gestational diabetes only with the second two. Obviously age and other things are a factor, but she was hinting that it might be more related to the men involved.

Elise (11:57) Sometimes, yeah. The thing is with gestational diabetes, we don't really know, right? There is a link with endometriosis and PCOS, but there are lots of women with those conditions who don't get it. Same with IVF - we have women who get gestational diabetes with IVF because of all the steroid injections beforehand, but then we also have women with IVF who don't get it. There's a lot we do know, but there's also a lot we don't.

Celia (12:21) And I think that's kind of confusing at the same time, because when you're trying to map it and understand it for yourself - where's the Venn diagram for me? How did this happen? Can I avoid it next time? And there's so much that's just impossible to confirm.

Elise (12:31) Yeah. I still remember I had this lady come in - bless her cotton socks, she was the fittest woman I'd ever met. Like an elite cyclist, and she ate so cleanly. Her fasting levels were 6.2. She wasn't sick, she had no family history, no IVF, nothing. She just didn't fit any of the typical categories. Her placental hormones were raging at the point of her OGTT. It doesn't discriminate.

Celia (13:10) No, definitely doesn't. Getting sick during pregnancy should be illegal in my opinion. But let's talk about it because it can happen. It actually happened to me - I got shingles about two months ago, which I would not recommend. I'm okay now. It's just that right as I got my second trimester energy back...

Elise (13:21) Oh, when you're pregnant! Gosh, I didn't know that was a thing. Well, I'm glad you're okay.

Celia (13:37) Yes, but I wasn't monitoring my levels at the time, so I can't speak to what happened personally. But can you talk a bit about how getting sick can throw your levels off?

Elise (13:48) Absolutely. It's the same thing as the stress hormones - cortisol. When you're ill, your body is working hard to try and fight the infection. It does not give a thought to what your glucose is doing. You might get fevers, chills - it's your body's way of fighting. Your sleep will be impacted too. And it's also worth remembering that when you're pregnant, your body is working to protect the baby you're growing, so it might take you longer to kick an infection than if you weren't pregnant. It's important to be kind to yourself, give yourself that extra time to rest and recover, plenty of water and good nutrition. I've had a lot of women who've had their OGTT around the 24-week mark but had the flu right before. Their OGTT came up positive, but the obstetrician suggested they try again in two weeks once they were better - and two weeks later they passed. It shows just how much of an impact it has. Who knows what your OGTT would have looked like when you had shingles - that's one heck of an infection. You did well there, Celia.

Celia (14:57) Yeah. When do you think it's worth checking in with your healthcare provider when you're sick? Should you just let them know in general, or is there a point where you think, this actually isn't getting any better?

Elise (15:15) Really good question. Honestly, there's never a silly time to get in touch. I always remember a midwife saying, if you're concerned, just present. If you're concerned about baby's movements changing, or you've been unwell - I got stung by a blue bottle at about 36 weeks pregnant with my first baby and I felt fine. But my husband was freaking out - what if something got through the placenta? So we rang the midwives. We're on the Gold Coast and they weren't quite sure, which was funny given how common it is up here. They ended up ringing our obstetrician and she said it's fine - as long as I felt okay and could feel baby moving, the venom from a blue bottle doesn't cross the placenta. But that's the same thing when you're sick - if you're concerned, or your partner is, just get in touch. In terms of a general guideline, I'd usually say give it a week. If things aren't improving after a week, get in touch with your healthcare team or at least your GP. Your baby is taking everything it needs regardless, but you need to look after yourself too - it's going to be a miserable pregnancy if you can't manage that at a bare minimum. You should at least be improving.

Celia (16:38) Yeah, and it's good to find out what options are actually available to support you getting better. When I went to the doctor for my shingles, everything he looked at had a big warning saying can't take in pregnancy. There was eventually something I could use - gosh, I can't remember the name right now, it's a natural kind of spray, starts with a C. I'll remember it later. But that actually gave me some relief - it was all I could really do.

Elise (17:08) And honestly, a lot of the time GPs just err on the side of caution because it's not their specialty. If you have the opportunity to chat with an obstetrician, this is what they know. I've had women come in with really itchy skin rashes from shingles who were so irritated they weren't sleeping, they were so stressed, their glucose was everywhere. And their obstetrician had clearance to provide a medication that a pharmacist or GP might not prescribe, but at a certain level it's safe. So get in touch with those specialists - they might know some alternatives. If you're not coping, reach out.

Celia (17:45) Yeah. Better to have something.

Elise (17:47) Exactly.

Celia (17:49) Okay. Well, this is actually relevant to my personal to-do list - I need to get my whooping cough vaccination. I've heard that vaccinations can also have temporary effects on levels too. Is that true?

Elise (17:57) Yes, though it does depend on the person. I was wearing a CGM when I was pregnant and had my whooping cough vaccine, and there was no difference for me personally - but I also didn't have any reaction to it. I imagine that if a woman had an immune response - like with the flu shot, where sometimes you get a fever for 24 hours or feel a bit run down or sore - that would likely cause an increase in glucose levels. It's related to that same cortisol and hormone increase. Your body's immune response is trying to say, hey, hold on, this isn't an infection, this is just a vaccine. You could say there might be a temporary insulin resistance where glucose levels run a bit higher. It really depends on the individual, but it's a really interesting point.

Celia (18:58) Yeah, definitely not guaranteed to happen, but good to be aware. Like if you do see an increase, you can go, oh, I had my flu shot yesterday - I'll make a note for my team so when they see that higher number, it explains it.

Elise (19:03) Exactly. And as long as it resolves, that's generally what we see - if glucose levels go up because of a vaccine or illness or stress from moving or stress at work, they should come back down. But if you're getting to day three and it's still elevated, maybe we need to investigate further. If it's coming back down and you're feeling better, that's a good sign.

Celia (19:35) Yeah. Are there any other surprising factors that can influence blood sugar levels?

Elise (19:43) I think people tend to forget about the non-conscious stress - all the tasks you have to remember, like paying bills, keeping track of appointments and scans, your toddler's Easter hat parade. The mental load of everything you have to keep on top of can play a really big impact. If you've got a supportive partner, being able to delegate some of that stress really helps. But I think in terms of the unknown stressors - the sickness, the lack of sleep, the general circulating stress - we've covered them pretty well. If you can, talk to the people around you and think about ways to try and manage that stress. Yeah.

Celia (20:26) Yep, makes sense. For women who feel like they're doing everything right but still seeing unexpected numbers, what would you want them to understand?

Elise (20:35) There's more to you than numbers. If the readings aren't hitting the target your healthcare provider has set - and I hate the word target - as long as you feel okay, and as long as baby's okay and you can feel them moving and they're growing along their curve, just talk to your healthcare providers. And remember, you've also got your mother's instinct. If baby was at the 20th percentile at your morphology scan and then suddenly at the 95th percentile at your next check, yeah, we'd want to keep an eye on that. But if things are tracking along and you're feeling okay and baby's movements are fine, it's important to remember that the numbers on that meter do not define you. It's also important to remember - have you ever done a rage check?

Celia (21:23) What's a rage check?

Elise (21:31) A rage check is where you do a reading, get a number you didn't want to see - say it's 6 - and so you immediately do another one. And then it comes back at 6.2. It's not that it's changed, it's just that there's natural variation in the glucose meter - about a 10% variation is normal. So we always say don't do back-to-back tests because you're going to get different numbers. The only real accuracy comes from a blood test, and we're obviously not going to do four blood tests a day. But if people are getting numbers they don't want to see, reach out to your healthcare provider. Hopefully you've got contacts you can reach, or at the very least the midwife team at the hospital or centre where you'll be birthing. Reach out if you're concerned. That's the important thing.

Celia (22:10) I love rage checking. No.

Elise (22:12) No rage checks. It doesn't help. Sometimes you might get a lower number the second time, sometimes it might go the other way.

Celia (22:17) Yeah. Well, thank you so much. It just helps to understand what some of those other influences are, and it helps to hear that it's probably happening to everyone in some capacity.

Elise (22:24) It's normal. Yep.

Celia (22:27) So hopefully feeling a bit more reassured after hearing that.

Elise (22:30) I hope so. Look, you can do the best you can with sleep and trying to have your water before 4pm - but let's face it, when baby's sitting on your bladder, you're probably going to pee at midnight. And that's okay. You're not alone. There's probably other people with the bathroom light on at that same time. You can only do what you can do.

Celia (22:48) Yes, true. You can only do your best. Well, thank you so much, Elise. Really appreciate having you on.

Elise (23:01) Thanks so much for having me. Thanks, Celia.