3 Most Surprising Lessons from my continuous blood glucose monitor

lentils & hummus

[dropcap style=”font-size: 60px; color: #00adef;”] I[/dropcap]t’s been over 4 years since I was diagnosed with gestational diabetes.

So I’m comfortable with managing my blood sugar by eating low carb.

But as a girl with 2 science degrees, I do love a good experiment.

And am always looking for ways to improve.

So for the last 2 weeks I’ve been using a continuous blood glucose monitor to track my sugars 24/7.

Super fun!

Here’s what surprised me this time.

3 surprising lessons from my continuous blood glucose monitor.

1. What you eat during the day impacts night blood sugar.

I hadn’t noticed this before but the biggest surprise this time wasn’t my results during the the day.

It was the spikes some food caused when I was asleep. Especially around midnight.

The most alarming of these was after Fergal’s birthday cake.

I had thought things weren’t too bad during the day.

But when I woke up to my highest spike ever (see below). I decided there won’t be any more butter cream frosting for me.

Glucose graphs

Easy decision.

2. Lentils are OK!

My prime motivation for testing this time was to see the actual impact of lentils because I’m keen to reintroduce them.

My first test – a delicious Spiced Lentil Soup with Tahini Yoghurt seemed fine at the time, but gave another middle of the night shock (see below).

Glucose graphs

But I wasn’t giving up that easily. What if I reduced the quantity?

So I re-tested with a Sausage & Lentilotto (like risotto made with red lentils). With a small serving of lentils (100g / 3.5oz) and the sausages it was smooth sailing (see below). All night.

Glucose graphs

Bring on the lentils!

In modest servings of course ;)

3. Spitting out doesn’t work.

I’m a bit ashamed about sharing this one.

But ever since my days of being a wine maker, and learning how to spit out when tasting, I’ve had this bad habit of eating and spitting things out.

Remember that graph above from the Birthday cake? That was even with me spitting out the frosting.

An excellent motivator to stop. Knowledge really is power.

What do you think?

Is it helpful when I share about my diabetes journey? Would you like to see a followup of the other things I tested? Let me know in the comments below.

And have fun in the kitchen!

With love
Jules x

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  • My son-in-law and grandson are Type 1 diabetic so learning ways to cook for them is always appreciated!

    • All my recipes for the last 4 years have been diabetic friendly Bonnie – so you’re in the right place!

      • I’ve been diabetic for years (Type 2) and I relate with you on how you approach your food intake. Months ago, my doctors have taken me off medications since my blood sugar has been consistently under 7 A1C.

        • I have A1 below 6.9 but my doctor does not want to take me off medication. The diabetes association have brought down the limits however, still my doctor persists that I have been on medication for a long time and thus, this decreased number is not applicable to me……

          • Aren’t the continuous monitors the best? My sister dropped her A1C from 9 to 7 (US).

            I have found that nighttime isn’t my bad time. I thought it was since my BS would be high in the mornings when I took it. Instead, mine climbs rapidly from the time I wake up until I can take it 15-20 minutes later.

            Unfortunately, I spend that time making sure one of my cats eats enough so I can give her an insulin shot (newly diagnosed). Did you know they have used the monitors on cats? We are so not there yet (thank goodness) because these sensors are expensive!

    • Still struggling to re/educate my husband (73) type2 and my self of course in Best And interesting things to prepare !
      Thank you, Chris P

  • As one who is back to being borderline diabetic (A1c = 5.9), apparently most likely due to all the stress we’ve been through in the last few months, I am very interested to know what your tests turn up. I would also like to be able to re-introduce beans and lentils into my diet, so again your experiments are helpful. I am rarely tempted to try anything like birthday cake (we missed my having to eat some of my own by being thrown off our cruise ship very early), but I did have to eat our table mates’ anniversary cake. Which makes me wonder how long the effects of birthday cake spikes last? I would tend to guess that any such spike would contribute to A1c levels.

    • Hi Susan

      It took about 36 hours to get back to normal after the cake. If it’s a one-off event in the 3 months the A1C is looking at I don’t think it would have a siginificant impact – BUT if it was every week, that would be a different story.

      The lentil experiment was really fun – I am going to include them again but only once a week or so and in small quantities.

  • I am also diabetic, on insulin, and suspect I might have spikes during the night

    . I am interested in your personal experiences with certain foods, but woud also like to know about the continuous blood sugar monitor.

    • Hi Carolyn

      Definitely talk to your doctor about continuous monitoring – it’s so helpful. Especially if you’re on insulin.

    • dear jules
      my father had diabetes and he always took extra insuline when he ate something ‚wrong‘
      i love to read about your experiences because maybe diabetes gets me too and i‘m very interested about diet and health
      so please share your knowledge with us
      lg birgit

  • I too am very interested in your experiments. I appreciate the lentil tests as it answered my question about smaller portions and has added to my menu options. Thanks for sharing.

  • I’m not diabetic but I know very little about it so, very interested in further experiments!
    & If you can devise any experiments that help with implement lentils to my pulse-resistant husband, please let me know! = )

  • This is a kind information.
    What all i experienced, if we reduce the belly fat, almost your mitochondria starts working again. And it is helpful to reduce the spikes, greater he belly fat, higher spikes in BS. Moreover exercise is key to make dowm BS even while sleeping. Also dawn phenomenon gets activated in night, so better not to check BS during 3 am till 6 am. Cutting long into short, one of my doctor friend was saying perfectly, he said, what you eat, you need to observe it.. thats all.
    My journey is from HBAIC 10.2 to 5.9. Then after 1 year, it became 6.7 again it comeback to 6.2.. all the the time we have to be calm and stressless. One good and big news is fractyl has discovered the treatment of T2D, for more information type on google fractyl new and check the 30th march news. Trust men it is break through in T2DZ HISTORY

    • Normally 3 am or in the middle of the night blood sugar spikes is due to the so called Dawn phenomenon. As you are eating less during the evening or night, you tend to starved yourself, hence the body in its effort to avoid hypoglycemia during sleep, it releases your spared glucose from your muscles and liver into the blood stream. This resulted in getting high fasting blood sugar reading early in the morning. Nevertheless, food factors must be part of its causes. Perfectly said, ” What you eat, you need to observe it”.

  • Great article. in January my HBA1C was 10.9 and decided to change my diet. In morning 3 full eggs with 100g of vegetables, afternoon 150g chicken and 250 g of vegetables and for dinner 150g of chicken/paneer/tofu with 259 g vegetables. Within a week if starting my BS dropped and had to stop taking my medicine. Although I do test my BS, 2 hours after every meal. It’s been over six months and still without medicine and my morning sugar is around 90 and 2 hours after meal is 120. Glad to find this article as I have been on same diet for 6 months and would love to try new recipes.

  • You have orthorexia, please see a doctor, living in your head must be absolutely miserable. FYI, alcohol causes 7 types of cancer. I don’t think lentils are what you need to worry about.

    • That was really interesting. I’d love to see more studies with the Libre. I dont understand how spitting out frosting can have that much of a spike. Is the sugar absorbed into the blood that quickly?? Is everything—could you get the benefits of some vitamins by spitting out vegetables? (Not that I’d do that but interesting from a science-y view)

  • Hi Jules, it is nice reading your posting and experience. I am diagnosed pre-diabetic. I don’t know how to cook but try to reduce carb diet. Looking forward to read more updates.
    Thank you. Isaac

    • Thanks Isaac!

      You can get into cooking – just start slowly with simple recipes like the ones here on Stonesoup :)

  • I am always interested in learning more ….. when I asked my doctor about the number going up while I was sleeping I was told it was not affected by what I ate that day …. yet I experienced the same as you. If I kept my carbs low and did not snack just before bed ( i was also advised to have have a bedtime snack which I very soon gave up after realizing it could be making my sugar spike whike I slept) the low carbs helped greatly ! So yes yes yes ….. limit those carbs???

    • Isn’t it crazy the idea to snack before bed Leslie – glad you also figured that one out for yourself :)

  • Do you have type 2 diabetes? Gestational diabetes occurs only during pregnancy.

    • I don’t have gestational or type 2 any more Carolyn because I changed the way I eat. But if I ate a standard diet I hate to think where I’d be :)

  • Glad to see something positive. I’m type 2 hba down from 68 to 39 but hard work getting there and I’d like to hear more about what I can eat rather than what I can’t eat.

    • Good for you Mac!
      I think focusing on what I can eat really makes a big difference for me too.
      There are so many delicious low carb foods to enjoy – I don’t ever feel deprived :)

  • Hi, am type 2 diab and kindy i would request for more information on what to eat best,
    Thank u
    Julius, Kenya

  • I manage my diabetes well by not eating any food again from 7 o’clock in the night and in the morning I eat normal and same in afternoon I reduce my food,I tried it over 3 months now,today 2 of my medication was struck off hurray.

  • I am glad I saw your article Jules. I am pre-diabetic and I need to lower my A1C. This is very scary to me. I need to act fast before I become a diabetic. Your article and the questions people have are so informative and helpful. Keep up the good work.

    • Give up Bread, Give up all Sugars,
      No Tortillas, No Flour.
      Munch on Vegetables – Broccoli,
      Green Beans, etc.
      No Buns, No Fries, No Potatoes.
      Exercise – do twists while watching TV, march in place, grab 20 lb weights, lift often.
      No Fruits till you drop weight, Numbers – move, exercise

      • Hey Greg

        I disagree with the need to ‘give up’ anything – for me it’s all about removing the desire for bread, sugar, tortillas, flour. When I understand the damage they do to my body I don’t want them.

  • Very interesting. Please keep posting experiments with different foods.
    I am also using CGM out of curiosity.

  • Thanks for these insights. A lot of our food in this part of the world is carb based. Staying strict on no or low carbs recipes is really not easy but with discipline we are coping. At the end it’s a marathon and not a sprint.

    • Yes it’s a marathon Egemba!

      I find focusing on what I can and want to eat really helpful. There are so many delicious low carb foods available. I never feel like I’m missing out – especially whan I know the damage that high carb choices are making.

      You can do it!

  • good article….3 weeks ago with no warning l was diagnosed type 2….since then I have went strict low carb and my fasting bs is just a shade over 100 most mornings.the nightime spikes are hard to explain a doctor told me.metformin works during the night better than the day doses lve read. maybe we spike in our sleep because theres no activity? i know I try to fast from 4pm until 5 am to lower night time blood sugars.

    • Good for you Mark – low carb is amazing for getting results.

      I don’t have any knowledge about metformin – but night time spikes have something to do with cortisol I believe.

      Keep up the great work!

      • Jules,
        I have had type 2 diabetes since around the year 2000, diagnosed roughly a year after I had a pregnancy with gestational diabetes.
        My Father developed diabetes in his early 30’s. Maybe 34, close to mid-thirties. Me and my 4 siblings each have diabetes or hypoglycemia, which can develop into diabetes. (My younger brother got his diagnosis in his early 30’s, and he was the youngest, age-wise to get it, and we were all surprised. He was not at all fat as a child, and seemed to always be healthy.)
        It definitely has a genetic component in our family, probably on my mother’s side of the family too. She was diagnosed in her 50’s, and that side of the family has a lot of diabetics, all developed in older adulthood (50’s and older)…some of them, on my mother’s side are quite overweight. My dad was never overweight.

        I know about the Dawn Phenomenon. I experience that myself. From a book by Dr. Julian Whitaker, I learned the term, and he describes it as the liver dumping sugar into the bloodstream overnight. (I think I’m remembering his description correctly. His book is entitled, “Reversing Diabetes”.)
        I have gleaned helpful insight from 2 other books/authors. One is “Diabetes” by Dr. James W. Anderson, published in 1981 and 1982. His approach is different because he says to eat high fiber and complex carbohydrates. His ideas are based on medical research. You might want to find a copy of it just to see what his research showed him.
        The last book I’ll mention here is entitled, “How to Prevent and Treat Diabetes with Natural Medicine” by Michael Murray, N.D.
        If you have not yet looked into any of these books, you are in for a treat, especially since you like science and research and food.
        (All these books are backed by medical research…but each one is a little different, as you will find if you read them.)

        One more thing. I learned along the way to eat some protein alongside the carbs, as it lessens the carbs impact. If I sneak a spoonful of icing from the leftovers after a birthday cake, I quite often “chase it” with a piece of chicken!
        I hope any of this information is helpful.
        I appreciate your “diabetes talk”. Keep addressing it, I think it is important for many people.
        Also I think folks mainly need to experiment to find what best helps them manage their blood sugar.

        • Oh wow Cynthia
          I didn’t know you also had diabetes.
          Thanks for the encouragement to talk about it more.
          And thanks for the book recommendations!

  • Thank you for sharing this! I greatly reduced my alcohol intake over the past few years and noticed that any time I have alcohol now, I have a weird spike in heart rate in the middle of the night. Sometimes it wakes me up and I can’t get back to sleep. I definitely suspected the sugar in the alcohol but have always been surprised that it happens even with 1 glass of wine. I’ve had this happen with too many carbs, too! So weird.
    Fortunately/unfortunately, I can’t even drink any more because we were in a car wreck in March and even a glass of wine leaves me with serious brain inflammation and a hangover that lasts multiple days. Definitely makes it easier to give up!

    • Talk to a doctor about your symptoms. I’m type 2 and had what I thought was severe heartburn during the night- it would wake me up. About 5 months after this started I had a major heart attack, the kind that’s called a widowmaker. I got treatment fast, then started low carb with intermittent fasting – basically eating 1.5 meals per day of low carb. My hga1c went from 12 to 6 in 3 or 4 months.
      Always looking for more recipes, and I find your experiment very interesting.

    • I have had a similar experience with alcohol Catherine – I actually don’t desire it any more which is incredibly strange for me given I used to be a wine maker!

      There are lots of benefits from avoiding alcohol. :)

  • I was diagnosed with gestation diabetes so from then i decided to eat health and reduce my weight to avoid type 2 diabetes..I sometimes monitor my blood sugar morning and during the day but would love to monitor it during my sleep what did you use yours to monitor during your sleep tia?

    • Hi Angelah!

      I use the Abbott Freestyle Libra – it measures constantly for 2 week. It’s expensive but worth the insights.

  • I have been diagnosed with GD and the Libre really helped me see how to control my sugar levels and how exercise etc helped keep them level. I’m curious if you went from GD into type 2 diabetes? Or did the GD diagnosis just really help you learn the healthy balanced way of eating?

  • I have been on a low carb diet so to speak for the last eighteen months now, during that time I have indeed lost weight to the tune of 35 kilograms , I walk about 6 to 7 klm five days a week , my A1C up until recent times was marginal , last blood test was up , we knew we would eventually have to go back on insulin, the problem is my liver producers glucose, to feed the vital organs whilst asleep , the result being high morning readings…..

  • You thought the birthday cake gave you a spike… Wait ’till you see commercial pizza with its high fructose corn syrup infused sauce!

  • I have been a type 2 diabetic for 20 years. I am on insulin now and I have the Libre sensor on my arm and I have learned a lot. I am on a low carb diet, no sodas, no bread, no chips, no fried foods. I eat a lot of veggies, salads, a lot of high protein foods grilled chicken and fish. A lot has to do with how much you eat. If we fall off the wagon get up shake it off, and start over.
    Don’t give up?

    • Definitely don’t give up Tina! And I agree the amount you eat has a massive impact. I had a very small portion of home made ravioli with my almond pasta and it was fine. I enjoyed it but didn’t need any more. There are always options :)

  • Hi !!! Loved your graphs .
    I have thought a lot about spitting chocolate , cake etc .
    Love your honesty !!!

  • It would be a real help to hear about your journey with looking after your blood sugar with your recipes and what works.

  • It is so helpful to read of your diabetes journey. Really appreciate your sharing this and all its meal planning implications

  • I am pre type 2 monitoring 3-5 times and have also noticed late evening spike. My body is slow to process food is my guess so have to watch day time eating.

    • It’s hard when you’re only monitoring a few times a day D. But the earlier in the day you have your last bite the less you’ll have those late evening spikes.

      I’m planning to experiment with having a larger meal at lunch and a smaller meal for dinner to help with this.

  • When my 43 yo son died of chronic kidney disease and heart failure 2* to long time hypertension, I immediately checked my urine and found 4+ sugar. WOW Having been healthy carb for most of the last 50 years (with yo yo dieting, lapses, and binges), I had recently adopted a healthy hi carb diet consisting mainly of beans, rice, and hi fat dairy supplements. I enjoyed my whole grain bread made with my homeground wheat. The day I learned of my son’s death, I stopped eating everything except dark leafy greens, meat, fish, and eggs; within days my urine tested negative for sugar. I got a glucometer, subscribed to a carb monitoring app, and continued with a weight loss diet consisting of only 13 grams carbs per day (a 70/25/5 LCHF diet of only 1053 kcal/day). I lost weight (My ultimate goal was a 40-50lb weight loss), my blood sugars during the day rarely went over 110 mg%, but my early morning fasting blood sugars often were in the 100s with an almost weekly spike into the teens and higher. My a1c was 5.8 mmol%. I researched the web and YouTube and found the advice from the AMA and ADA less than helpful, so I decided to look more seriously into Keto. I had originally thought it a truly unhealthful diet, and I still do. My weight loss stalled at a 1000 kcal/day, and I was unhappy with my A1c and high fasting sugars. I adapted to a daily 16/8 IF schedule and strived to eat no later than 1600 hrs. The more I read about keto and ketosis, the more sense it made to me. My blood sugars dropped slowly but my weight did not. I upped my caloric intake with additional fats and started 36 hr fasts, up to 3x/week. Got a ketone meter, dropped nearly all my carbs and increased fluids. Results: my FBS has dropped consistently into the 80’s and my blood sugars during the day rarely exceed 100 mgs%. My weight remains pretty much unchanged. OKnews, BUT – my blood pressure has dropped out of sight. Salt water and licorice extract seem to help. I take supplements, my ketones are high, and I have to work to avoid dehydration. When I get this handled, I may try extended fasting to lose the last 20 lbs or so and gradually reintroduce carbs into my diet.
    The goal of all this is reduce insulin and insulin resistance, and I believe it is working. The weight loss is ostensibly a means to an end, but of course it is so nice it might well be the end. My mother died of diabetic complications, as did her mother before her; my mom’s cousins, and many of their children, have T2D as well; of my two siblings, one is an insulin dependent T2D, and the other is so overweight he might well be. My son, whose diagnosis did not include diabetes, died from a set of related diseases I now know as metabolic syndrome, a hormonal disorder stemming from, and driven by, high insulin levels and insulin resistance. Another, different, form of “Diabetes”? So, yeah, there might be some genes involved.
    Many doctors today want to simply MANAGE the symptoms of diabetes, not cure or reverse them. The ADA is no better. People will generally need to take on the responsibility themselves, coz no one else is going to do it for them. Support groups are great! So YES, I applaud! and welcome this invitation to get more LC recipes that support a Diabetic lifestyle. It’s not a popular mainstream venue yet, but it should be. My family keeps its diabetes secret, like it’s a dirty disease; I mentioned the D word ONCE in a letter to my cousins in the East and I haven’t heard from them since (think they’d rather have syphilis). The secrecy and shame keeps them chained to an uncomfortable and shortened lifespan. I, for one, would like to hear about people’s struggles with blood sugars and what works (and doesn’t) work for them – and I am willing to share my experiences.
    I should be censored for such a long response – but I am hoping it can add to your data and insights, Jules, so that it benefits at least one person.

  • Hi Jules, love reading about your diabetes journey and information sharing. I also had GD in my second pregnancy and am currently breastfeeding my 8 month old. Breastfeeding can help lower blood sugar apparently and has a protective factor. I am concerned about developing type 2 down the track however. How long after your GD was your type 2 diagnosis?

  • Personally, I would love to hear more about your 24/7 blood sugar tracking in response to your ‘experiments’. I’m not diabetic and have no need for a monitor so I can’t really get this kind of data anywhere else.

  • This is helpful to know, I have been recently diagnosed diabetes 2 so will be starting to look at better meal ideas. Rice is will be hard to replace for me. Any suggestions?

    • Hi Roshika!

      You’re in the right place if you’re looking for better meal ideas.

      The first thing change I would make with rice is to watch your portions – the amount you eat makes a big difference.

      And choosing lower GI varieties like Doongara or Basmati will help. Also cooking and cooling the rice and then reheating as in fried rice also helps lower the impact on blood sugar.

      But if you’re ready for some radical change, I just serve myself extra veggies instead of rice. and I never miss it :)


  • Hi Jules,
    Very interesting about the spikes! And variations to try, I’m type 1 for past 25 years and always looking for a better way which is why I follow and love your recipes. Thank you very much for sharing.
    One question is the CGMS just on trial or is it permanent?

    • It’s just a trial Jules – although if I was super rich I’d wear one all the time – it’s so fascinating.

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