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Conquer Your Weight

Episode #9: My Continuous Blood Glucose Monitor Experiment

Show Notes

April 20, 2022

This week I'm going to tell you about my two-week experiment wearing a continuous glucose monitor. I'll share with you how sugar and flour cause a spike in blood sugar, where complex carbohydrates balanced with fats and proteins lead to a much more rounded response. There were a few foods that surprised me. Come learn about my experiment!


Dr. Sarah Stombaugh: This is Dr. Sarah Stombaugh and you are listening to the Conquer Your Weight podcast, episode number nine. Announcer: Welcome to the Conquer Your Weight podcast where you will learn to understand your mind and body so you can achieve long-term weight loss. Here's your host obesity medicine physician and life coach, Dr. Sarah Stombaugh. Dr. Sarah Stombaugh: Hey everyone, welcome back. I am coming to you from vacation in Florida right now I've got a makeshift recording studio set up in the master bedroom closet of the condo we're staying in and hopefully we'll get pretty good sound quality based on my test recording. I think we're going to be just fine. I think you know, a lot of times when people think of recording a podcast, I have this idea that they imagine a podcaster recording from a beautiful soundproof studio space. But the reality is most podcasters actually record straight from their closet. And a closet is great space because it's often filled with clothes and other items that help to absorb sound and so it helps cut down on any reverberations and echoes and that sort of thing. And when the pandemic very first started, I remember an NPR host saying she was recording the day's show from her closet and that really stuck with me. I was like, you know what? If it's good enough for NPR, it's good enough for Conquer Your Weight. So when I'm home, I record from my bedroom closet and I'm doing the same on vacation right now. We're staying in a lovely condo and it's furnished by the type of people who believe in using just as many throw pillows as possible to decorate each bed. There are literally like four different regular pillows, which is excellent. I appreciate those choices. Then let's count like 1, 2, 3, 4, 5, 6, 7 decorative pillows, I think so 11 pillows total on the bed and we're the type of people who make our bed most mornings, but 11 pillows feels like just a few too many pillows to put back on the bed every day of occasion. So luckily for you that means they have about 11 pillows in the master bedroom closet right now improving my sound quality for you, I think the only thing that will detract from my sound quality right now is my own voice because oh my gosh y'all, I have my third illness in three weeks. I'm sure I'm not the only one in this boat, but my immune system has been working overtime recently. I don't think I had a single illness from March of 2020 until fall of 2021. But between my out of shape immune system and two young kids who bring home every dreamable illness and pregnancy, I have spent a lot of time sick over the last couple of months and that's right, maybe a weird way to announce pregnancy, but I am pregnant right now. We have a little girl joining our family this fall. I can't wait to share my journey with you all and we may have to have an episode or two dedicated to pregnancy in the future. Well, now that you've had a bit of an update about my life, let's dive into today's episode. I hope you're as excited as I am because we are going to talk about my two-week experiment with a continuous glucose monitor. So I was telling you about it last week if you tuned in, but a continuous glucose monitor, it's a small wearable medical device and it measures your blood sugar continuously for 14 days and I talk about the impact of certain foods on our blood sugar so often and there's data that shows it. So data that shows how people's blood sugar levels are impacted by the foods that we eat. But I wanted to see it for myself in a real-life person. So who better than me to do that? So I've been planning this experiment for a while and I finally just jumped right in and did it starting a few days before my birthday and I knew it was the perfect time because I always eat a little outside of my regular routine for my birthday. I also had family coming into town right beforehand. What I didn't anticipate was that I would be getting a terrible upper respiratory illness followed then by a gastrointestinal illness. During those two weeks I was wearing the monitor and for good or for bad, it gave me the opportunity to monitor my blood sugar in some wildly different circumstances. Overall, the experiment proved exactly what I expected, which is that sugar and flour causes spike in blood sugar where complex carbohydrates, especially when balanced with fats and proteins lead to a much more rounded response. There were a few foods that did surprise me though, so let me tell you a bit about the experiment. There are so many foods that claim to be a good food choice, but they're actually laden with sugar. Before the experiment, I was fantasizing about all of the different foods I should buy from the grocery store, things like granola bars, breakfast cereal, instant oatmeal and flavored yogurt just so I could show the effects of those on blood sugar. The interesting thing is I never actually went out and purchased any of those. I sort of let the experiment play out and I had plenty of opportunities to see how my blood sugar was impacted by a variety of foods. Right at the beginning of the experiment, I got to see how banana bread impacted my blood sugar. My mom is a great cook and baker and she has recently gotten on a banana bread kick. Likely driven by the fact that my four year old son is totally obsessed with banana bread and of course my mom is happy to indulge him and honestly I'm not sure who's more excited about it. My mom watching my son enjoy the banana bread or my son actually eating the banana bread. Nonetheless, whenever my parents come to visit or when we visit them, I can count on a loaf of fresh banana bread and because I know there will be banana bread every time I see my mom, I get to decide how I want to handle that. Most commonly I plan to have a slice or two and I accommodate that into my food plan. So as I mentioned, my mom's most recent trip corresponded with my continuous glucose monitor experiment. So I had the chance to see what banana bread actually did to my blood sugar. And it's funny because banana bread is one of those foods that seems like it might not be that bad for you, especially if it's homemade, but if you've ever made banana bread, you know the main ingredients are flour, sugar, bananas and butter or maybe vegetable oil, but a.k.a carbs plus carbs plus carbs plus fat, there is nothing about the fact that it is homemade that makes it good for you. Sure, maybe you can substitute an applesauce for the butter or use whole wheat flour instead of all-purpose flour, but even then it's still a combination of very processed carbohydrates. It's not good for you. And I could see the proof straight in my blood sugar when I ate a slice of banana bread, my blood sugar spiked straight up and dropped straight down afterwards and that feeling of plummeting blood sugar feels really terrible for me and honestly for most people, if they stop and pay attention to what that feels like, and I'm not saying you can't eat banana bread or foods like it, but you need to be intentional about the quantity and the frequency with which you eat foods like that. And I've decided that it's okay to have a slice of banana bread a few times per year, but having it more frequently wouldn't serve me and my body and the nutrition goals I have for myself. It's also interesting how this experiment caused me to question some of the beliefs I have about food. We haven't talked terribly much about beliefs. I think I mentioned it a bit last week in life coaching 101, but beliefs are thoughts that you have over and over again. Most commonly they're passed down to us, so either from our family or our friends or society. Other times there are things we've come to believe sometimes without any logically like logical reasoning at all. For the longest time I've had this belief about a category of foods I call quote neutral foods. These foods are foods that aren't healthy but they aren't unhealthy either and there aren't any particular rules per se. I just make up the rules as I go. So for example, on one end of the spectrum would be something that's obviously healthy, so things like a hearty salad with lean protein or protein with a side of roasted vegetables. And on the other hand something like a cheeseburger or a slice of pizza would fall into the unhealthy foods category. And then there's everything else because honestly in my mind the majority of the foods would fall somewhere in the middle in this made up neutral food category. And this category would encompass anything from, I don't know, tacos, meatloaf, sushi, sandwiches, I could go on and on, but basically foods that aren't particularly good for you but aren't the worst for you either during the experiment, one of the foods I ate was tamales. Previously I would've put these right into that neutral food category. So something that's not good for you but not bad for you either. But let me tell you, tamales and other uh, processed corn foods like tortillas and tortilla chips were one of the biggest surprises of the experiment. Anytime I ate these foods, my blood sugar went crazy in one meal, I had two tamales and they were pretty big tamales, but oh my gosh, my blood sugar got up high and it stayed high more than when I ate cereal more than when I ate bread more than when I ate a brownie with ice cream. And when I stop and think about it, logically it makes sense, but I was still surprised by how drastic the blood sugars spike was. Tamales are made from cornmeal, which is basically ground up corn and corn is funny in that it's sort of a vegetable, but it's also sort of a grain. When you eat it on, its like in its whole form like corn on the cob, we will call it a vegetable. But when it's broken down into corn kernels, it's a grain nonetheless, its sweet flavor comes from the fact that it has a very high sugar content in the plant. So when you break down corn to make corn meal, you're taking an arty sweet grain and then processing it further. And most dishes like tamales are made without any leavening agents like baking soda or baking powder. So they're very dense. So when you eat something like a tamale, you're eating a large quantity of a very processed and like extra sugary carbohydrate and tortillas and tortilla chips are very similar. So I have to be honest with you, after this continuous glucose monitor experiment, it's clear for me that tamal tamales have moved out of that neutral foods category and into the unhealthy foods category. And again, that doesn't mean I'm never going to eat them, but choosing to eat them will be a deliberate decision and therefore likely a food I will choose to eat less often. Alright, so let me tell you a bit about my actual birthday because the whole day was really good data for the experiment. The morning of my birthday wasn't too fancy. I had two scrambled eggs and a piece of toast with jam for breakfast and I'm almost embarrassed to admit, but I was actually surprised at how quickly and sharply my blood sugar spiked afterwards. I make my scrambled eggs with half and half for the liquid and I always add some cheese. So I was expecting the fats and protein in those eggs to balance out the toast and jam, but it really didn't as much as I was expecting. The bread I used for toast is a hundred percent whole grain and I had one serving of organic strawberry jam. And so the biggest takeaway from this meal where I guess there's two big takeaways, one is that bread is still bread, 100% whole grain bread is still pretty processed and you're going to see that reflected in your blood sugar. It might be better than a slice of wonder bread, but it's still bread. It's a lot different than eating a whole grain that hasn't been processed at all. And two organic jam is just as bad for your blood sugar as regular jam period. I have a lot of patients who get hung up on the, oh, but it's organic or oh, but it's homemade. And those things can certainly make a difference when it comes to things like chemicals or toxin exposure. But when we're looking at it strictly from a sugar perspective, organic jam offers no benefit over regular jam. It's literally just mixed fruit and sugar that's cooked down and therefore it ends up being a lot of processed sugar. Then for lunch that day my nanny brought me Wendy's takeout food. She got me Wendy's chicken nuggets, french fries and a Coke. And while it's not something I would usually eat, I was really grateful she brought it one, because it was just so thoughtful. But two, I'm not sure I would've ever purchased it myself even for the sake of my continuous blood glucose monitor experiment. And let me tell you, this one meal spiked my blood sugar the quickest and the highest of any of the meals I ate during my two-week experiment. My blood sugar got up to 180, which is really pretty high for someone who has no known insulin resistance or diabetes at all. And then my blood sugar fell just as quickly as it spiked up, which left me with that terrible low blood sugar-like nausea, hunger hanger feeling. And I ended up eating an afternoon snack that day, which is something I very rarely do because I usually don't feel like I need to because that afternoon I was feeling like oh my gosh, if I don't eat I'm going to die. And so that tells you a lot about what happens when your blood sugar is spiking up and then falling down and that how that impacts our food choices even later on in the day. And then there was my birthday dinner, which it isn't terribly surprising but it was just interesting because I learned a lot from it. So as I said, my mom had visited the weekend before my birthday and she brought me a homemade dish to bake on my birthday for my birthday dinner. We call them chicki-chagas. They are a super Americanized like Mexican dish, but it's basically like a shredded chicken and cream cheese rolled up into flour tortillas covered with tomato sauce and cheese on the side. I also had homemade refried bean dip, which is beans, chorizo, green chilies and cheese with a few tortilla chips. And then because it was my birthday, I followed dinner with a brownie and ice cream afterwards. And it was interesting because I was expecting my blood sugar to be insanely high from the tortilla and the tortilla chips and dessert. But interestingly it was a rounded hump. The interesting thing though is it took forever to come back to normal, like it was probably elevated for four or five hours at least, which is a super, super long time. So even though the number didn't get terribly high, it stayed high for a long time. And this is where I wish I had a video podcast. I mean maybe not 'cause I'm literally in this closet surrounded by pillows but I would love to bust out a whiteboard and show you some calculus and show you the area under the curve of my blood sugar. So if you imagine drawing my blood sugars onto a sheet of paper and then if you imagine that hump and you used a pencil to shade in, I'm like coloring right now as if you can see me. If you used a pencil to shade in the space underneath the blood sugar, you'd see there's a lot of area that was shaded in, meaning that even if the numbers didn't get particularly high, it did take my body a long time to process the energy from that meal. So ultimately it ended up being a lot of time spent in that energy-storing mode instead of the energy-burning mode. And just like before, it doesn't mean I won't eat these foods, but maybe I won't eat them all in the same day or I'll just choose to eat them on special occasions throughout the year as opposed to meals that I would choose regularly for myself. So then let me contrast my birthday to a more typical day for me. On my typical day I had plain full fat Greek yogurt with mixed berries and sliced almonds and then just a small sprinkle of granola on top for breakfast. I also had a plain black tea with it, no cream or sugar or anything For lunch I had leftovers. So I had one of the chickichagas with bean dip, uh, but no chips and certainly no dessert this time. And then for dinner we had a chicken caesar salad. So basically a Caesar salad with just grilled chicken on top of it. And I didn't have any snacks in between, which is my usual pattern. And on the blood sugar graph, I had these beautiful three nice rounded little humps in my blood sugar, which quickly came back to my baseline blood sugar after a couple of hours. Then towards the end of the experiment I was still fighting off my initial upper respiratory illness when I came down with norovirus, which is a gastrointestinal bug. And I literally don't think I've been so miserable in my adult life. Excuse me, I was so sick with norovirus, I completely forgot I was still fighting off that upper respiratory illness. I woke up sick or like just feeling kind of nauseated that morning. So I ended up skipping breakfast and then by mid-morning I started getting sick. I'll spare you the details, but I'll just tell you I had a lot coming out and nothing going in. And what was so interesting to see was that my blood sugar was stable all day long. Of course there were little, you know, teeny tiny fluctuations up and down, but it really stayed consistent in the seventies and eighties range all day long. And I would not have willingly done a 24-hour fast or maybe even longer. It might have been like 36 hours for the sake of this experiment, especially because of my pregnancy. But I didn't really have a choice here. It's interesting though because it was so reassuring to see that my body was a hundred percent capable of handling that. A lot of times we experience hunger and we're convinced that we need to eat right here right now. But I promise you if you have a functioning pancreas and a functioning liver and just a little bit of fat stores, I promise you, you have all the energy you need right on your body in times where there is a lack of access to food, your body is amazing and it will find the energy it needs. And then a few days later I had recovered mostly from my back to back illnesses, but I still had this nasty lingering cough talking more than 30 seconds straight would trigger these terrible coughing episodes. And the best I had was cough drops and a humidifier, which to be honest was actually working pretty well. And one day in particular, I had been eating quite a few, excuse me, I had been eating quite healthy, and I checked my blood sugar that afternoon and it was 110 and I hadn't eaten any food in at least four or five hours for breakfast. I had had plain Greek yogurt with berries and almonds again with my cup of plain black tea. For lunch, I had scrambled eggs with avocado and salsa on top. And both of these foods would typically cause a rounded hump in my blood sugar that would last for an hour or maybe two with then a return back to my face fasting blood sugar numbers in that 70 to 80 range. And I know this because these are very common foods in my diet and I had eaten them previously during my experiment. So when I checked my blood sugar in the late afternoon to find that it was 110, I was shocked what had I possibly eaten? And you know what it was? It was the cough drops lots and lots and lots of cough drops. I had a constant stream of cough drops in my system that afternoon. And of course I know that cough drops are basically just sugar, but it's not something that I ever really consciously stopped to think about, at least for myself. I've definitely warned my patients about it, especially my patients who have diabetes and making sure they're careful about using cough drops maybe to use sugar-free cough drops. But it's honestly just not something I've had to worry about. So I pulled up the nutrition label for the Rico of cough drops I was having and they have three grams of sugar in each cough drop. So for perspective, there are four grams of sugar in a teaspoon and I had a lot of cough drops the A that afternoon. I honestly don't know how many because I was consuming them mindlessly, which is another reason why we shouldn't eat food mindlessly. But I had a lot like 15 cough drops that afternoon. And so if you imagine that I had 15 cough drops at three grams of sugar each, that's 45 grams of sugar, which is nearly a quarter cup of sugar. Can you imagine that? I like to, I have this like mental picture of using a quarter-cup measuring cup and then scooping sugar out of a sugar jar and just eating it like straight from that measuring cup. And it grosses me out so much to think of it that way. And don't get me wrong, my cough was terrible. I needed a solution and the cough drops were totally it. I don't think I would've done anything differently, but it was really eye-opening to see in just something worth thinking about. Hopefully no one has to eat cough drops like every single day, but it's certainly worth thinking about, especially if you do have diabetes or insulin resistance and you're struggling with that, that choosing a sugar-free option might make sense for you. So definitely a lot of things that were learned here. I hope that you learned as much from my experiment as I did. If you live in Illinois or Virginia and you'd like to be my patient, let me know and we can get you set up with a continuous glucose monitor to do the experiment for yourself. You can certainly also talk to your regular doctor about it as well. Please do note though, unless you have diabetes, your insurance is not going to pay for it. And even then only certain patients with diabetes are going to meet the criteria for continuous glucose monitor. But if paying out of pocket is an option for you, you are honestly able to get the two-week monitor for like probably 60 to a hundred dollars depending on where you live and what your preferred pharmacy is. So it may be worth considering. Well, I hope you enjoyed today's episode as much as I did. Next week we're going to talk about making a personalized food plan and we'll use some of the information we learned from the continuous glucose monitor experiment to reinforce what type of foods make sense to include or exclude from your food plan. Thank you so much for joining me today. If you'd like to learn more about me, head on over to my website at That's S-A-R-A-H-S-T-O-M-B-A-U-G-H-M-D dot com. If you live in Illinois or Virginia where I'm licensed to practice medicine and you'd like to work one-on-one with me, come on over to my weight loss practice, fill out the form and we'll get connected. If you've enjoyed today's podcast, please subscribe and leave me a rating or review wherever you listen to podcasts. Please share this with anyone who might benefit. Thank you so much for joining me. I look forward to seeing you next week. Bye-bye.
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