Coffee and Blood Glucose rise in Type 1

Hello fellow diabetics! I am 64 and have been Type 1, adult onset, for 28 years. I am not overweight and I eat a lower carb diet. I often experience the “dawn effect” discussed by Dr. Bernstein but lately I have noticed that with a very low carb breakfast of 2 hard boiled eggs, 2 turkey sausage links, salad and a slice of hard cheese I am noticing an unusual rise of BG. (this morning from 93 to 183 in 1 hour after 8 unites of Lantus and 2 units of Novolog.) It appears to be related to my drinking of 2-3 cups of strong black (Lavaza) coffee in the mornings because when I switch to 2-3 cups of Irish Tea I get much less of a rise in BG.
I would be interested in your experience with coffee and how it effects your BG. Also about any alternative coffee (like?) drinks that you have substituted or limits to the amount of coffee.
Thanks much!

The caffeine is likely creating insulin resistance, especially at high doses which you are consuming several cups. Try decaf

This is a common problem for most of us. We’ve often referred to “feet on the floor” glucose rises that seem independent of the actual time. I think this issue of blood sugar rises in the morning are due to a few different factors and those factors can rise and fall in strength. It’s part of the dynamic nature of diabetes.

To start with, many people, both diabetic and gluco-normal, tend to be insulin resistant in the morning. It’s part of a natural circadian rhythm that increases the hormone, cortisol, as a way to get us ready to start our day. It’s the body’s way give us enough energy to start another day.

Some things I’ve noticed have helped me. I do much better blood sugar-wise in the morning if I have refrained from any snacking after an early dinner the night before. I’m not sure what the mechanism of this action is but I do notice that it affects me.

Another key to good post-breakfast glucose for me is to make sure that I allow enough pre-bolus time before eating. I’ve found the best way to do this is to use a CGM and wait to eat until the glucose trace starts to take a decided trend downward.

I often-times experience a blood sugar rise after drinking my first cup of coffee long before breakfast. At times I’ve been able to adjust my pump basal rates to compensate for this. Do you pump?

My most successful tactic, however, is to use a 4-unit dose of Afrezza when I start to see my blood sugar rise. If you don’t use Afrezza, you might consider using a small intra-muscular injection to level things out.

Bottom line, the best practice I’ve found is to do the experiment, write stuff down, and you will likely find what works for you.

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I dose 2 units for a single cup of coffee in the morning. Don’t really know if the culprit is the coffee (for a rise comparable to yours) or the Synthroid pill I take. Drinking coffee releases adrenaline and that may be the problem. Anyway, the 2 units of Novolog does the job for me.

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I have the “feet-on-the-floor” high BG phenomenon as well. Once, fasting for a blood test, my BG went over 200. So, I decided if my body wants glucose, I will give it glucose - I put a teaspoon of honey in my coffee. Of course, I pre-bolus for it. I put cream in my coffee as well, which helps lower the gylcemic load a bit. I use local, raw honey as it is better for you overall, and, it has done wonders for my allergies. My endo thinks I’m crazy; my PCP thinks it’s genius.

Willow4, do you calculate 2 units per cup of coffee? This sounds immediately practical for me but I need more details.

Breakfast-wise I’m generally a zero-carb, coffee-only guy since forever. I occasionally treat myself to bacon and eggs, and very rarely some kind of pastry (if it’s a holiday or something), but as a rule: 1 cup w/light cream & Splenda. And I’ve been bolusing for it as 32grams since forever. Seems like a lot but that’s how it works out for me. Dunno if it’s just the caffeine (I only rarely break the 1-cup rule), or DP (I’ve always had a pretty severe struggle with that, though pumping has flattened it out), or feet-on-the-floor, which I gather is it’s own thing, or some combination of all of the above. But the 32-gram bolus works, so I’ve been doing it for decades.

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Terry4, I appreciate the detailed response.
I am familiar with the cortisol effect and glad you described your experience of many factors effecting the rise of BG in the mornings. Since my BG was at 93, I immediately ate after my Novolog (within 10 minutes. That is what has confused me.
I did drink a half cup of juice and 1/2 WASA cracker to bring my BG up before bed (I had taken too much insulin pre-dinner). So that may have influenced he higher than usual BG in addition to the coffee.
I will investigate Afrezza because my BG has remained high this morning and I just had to take another 4 units of Novolog in an attempt to bring it down. I am also under some stress at work as we face some software testing issues ahead of User Acceptance Testing tomorrow…SMILE.
Thanks again.

Josephine, please explain how adding the glucose in honey is causing your body to not have BG rise in the morning? Are you saying that our bodies are craving glucose so that the Cortisol effect continues more strongly when I eat a low carb breakfast? Do you drink coffee in the morning?
Further description of what you are experiencing might help us all on this morning BG rise issue.

I am not using a pump but am using the new InPen along with PredictBGL app and Clarity App on my iphone. However, high blood sugars are persisting.
I will also increase my Lantus 1 unit during the day.
I did have a low last night which likely complicated the BG morning rise as I have seen how the body over compensates for the low releasing hormones that raise BG.
Well, I must concentrate on work now. Thanks for everyone’s replies!

Here’s how my Afrezza dose worked this morning.


The glucose level dashed lines are 65 mg/dL for the lower one and 120 mg/dL for the upper one. You can see the upward trend starting at 4:24 am with starting my first cup of coffee. I waited until 5:18 am to take the Afrezza as sometimes my automated dosing system, Loop, can turn this around on its own. The Afrezza dose is noted here by “2U,” the equivalent dose of liquid insulin that I estimate. Within 15 minutes, the BG starts to sink and levels out in the 85-95 range about 90 minutes later.

I drink only one cup of coffee with a slosh of whipping cream and liquid Splenda. 2 units works for me. It may not work for you, however, but it may be a starting point that requires tweaking.

Terry4, I see Afrezza as only inhaled insulin. It seems you are talking about injecting it? Tell us more about how the dosing works!

Terry4, I see my misunderstanding. You are likely talking about an intramuscular injection of novolog instead of into fat? Is that right?

“If you don’t use Afrezza, you might consider using a small intra-muscular injection to level things out.”

To be precise, I don’t think caffeine causes insulin resistance in anyone, so much as it causes glucose release in some caffeine-sensitive individuals, similar to how stress and other sympathetic nervous system activation can result in increased glucose release from the liver via cortisol release.

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It raises cortisol, adrenaline (epinephrine), and other stress hormones related to insulin resistance

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I guess it’s in part semantics—I think of insulin as your insulin works less well. Those hormones in the short term are causing your liver to dump glucose which is why caffeine is causing a spike. Your insulin may well be just as effective, but you need to also bolus for the glucose dump.

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Personally, I don’t find that caffeine raises my bg’s. I don’t drink coffee, but I drink tea.

I have a 32oz iced coffee almost every morning. Just black, nothing in it. Was trained way back when to save every exchange I could so that meant no cream in coffee or tea, no mayo on sandwiches and just dry toast. What I would do to save those fat exchanges for butter on potatoes or dressing on salad.
I worked for Starbucks for 15 years and have a huge passion for coffee and thankfully I love it black not all the dessert coffees they have now. And I thankfully have never had any problems with coffee no matter what time of day. Again, the reality of how different each of us are! Hope you find a good answer for this one! I would hate to lose my coffee!

Yes, I am tending to think, that in my body, the coffee strongly increases adrenaline and other stress hormones resulting in a rising of my BG from the increased glucose release from the liver. I have started drinking Lavaza with a europress so that may have caused some changes in my body’s responses also. I will attempt to really reduce my coffee to a literal two cups from now on and see if that helps (along with trying 2 unites of Novolog added to my breakfast dose). I don’t mind drinking black tea and could make the change but I do love my morning coffee!