Coffee spiking

in the morning i have my 1st cup of coffee; i put a sizable amount of 1/2 'n 1/2 and Splenda in it. i don’t know if its the cream or the caffein or the splenda or the combo of all mixed together, but whatever it is, w/in 1/2 hr. my cgm just shoots ^ . at first i thought i was just being insulin resistant in the AM. but then i had a C after lunch. same thing. my BG does return to normal in about 2 hrs, but its just weird to me. if i forgo the coffee, i don’t spike.

anyone else have this problem? or, any suggestions about how they’ve avoided this (besides from not drinking coffee anymore) all suggestions and experiences welcome.

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I live for coffee! I love everything about coffee but I drink just plain old black coffee. Just the coffe and nothing but the coffee. Back in he old days I didn’t want to waste any of my exchanges to doctor up the coffee, so black won out and still drink it that way. Never have blood sugar issues with black coffee so I would guess it’s the extras added to it. Good luck with finding your answer. Like I said I’d be lost without it. As a matter a fact, I’m sitting at my favorite coffee shop before heading into work.

I have bg issues with coffee. It affects people in different ways. When I wake up, before my feet hit the floor, I test then bolus 0.8 units to avoid a coffee spike and DP. It works for me.

Sarah :four_leaf_clover:

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Coffee definitely makes me more insulin resistant that I otherwise would be. I’m pretty sensitive to caffeine anyway and I only drink one cup before I feel like I’ve had too much. I don’t really know what to do about it either, other than drink less coffee, but I suppose you could try taking one or two units of short acting insulin to balance it out. Do you know if this happens to your blood sugar in the morning when you are fasting? For me, regardless of eating breakfast, my blood sugar will spike in the morning until about early afternoon. I try to counter that with my long acting insulin, what time I eat dinner and short acting insulin as needed. Coffee always makes that morning spike worse for me. You’re not alone in this one, for sure!

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I have to bolus for my morning coffee–though the amount differs depending on whether I’m biking or driving to work (mostly I try to bike). On average I treat it as the equivalent of about 20g of carb. I have it with Splenda and light cream. Note that the latter is close to 0 carbs, whereas 1/2 and 1/2 has lactose in it (from the milk), so that’s going to play a role too. Either way, there’s also going to be some kind of delayed bump from the dairy fat, so there’s that as well. And in my case I think dawn phenomenon figures into it too.

People vary so much in how they respond to coffee (it’s kind of a perennial topic around here) that I think the one rule is that there isn’t any rule. You just have develop a rule of thumb for yourself by trial and error.

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If you skip coffee, does your BG still rise? I hate to suggest to anyone to skip their morning coffee but I’m wondering if coffee is just a correlation and not really causing the spike.


DrBB, i think you’re on to something that might work well for me: LITE CREAM. i’ve used it before, but not in a long long while. i don’t remember the consequences however. i know that its probably not the caffein, as i can have a diet soda w/out any spikes. i am VERY dairy sensitive and have to dual wave for anything as simple as yogurt or cottage cheese. i also have to account for 20grms of carbs for my coffee (at any time of day).


i can gain 75 points on a cup of coffee. It is a killer for my blood sugar. I usually avoid the stuff if i can

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Coffee has no noticeable effect on my bg. I drink a lot of coffee. This makes me wonder— black coffee has no carbs (or only minuscule traces if any). So it’s something else about people’s bodys’ reaction to it or caffeine that’s making their bg rise. Does black decaf coffee also affect those peoples bg?

20g of carbs @DrBB ? That’d be a big ol dose of novologn for me first thing in the morning just to choke down a cup of coffee… I’m happy it doesn’t affect me that way.

i think it might be the lactose in the 1/2 and 1/2. i am just about to research this.

someone on TuD suggested that it might be the 1/2 and 1/2 that is causing my spikes. i am going to investigate this. he said that it may be the lactose that is spiking me as caffeine, as in diet soda, doesn’t seem to bother me at all. i am very curious and ready to experiment.

what do you put in your coffee? anything? please get back to me; i am very interested.

i drink mine black. Always have. I believe that likely has something to do with the stimulate effect, but who knows.

Daisy Mae, I’m lactose intolerant so I add coconut milk. I have to add something to my coffee to avoid acid reflux. . There aren’t many carbs in coconut milk, even when it’s the sweetened type, and it’s also good for cooking and baking.

did an experiment his morning w/ my coffee. i pre-bolused for coffee and eggs. instead of covering 20 gms of carbs for the coffee, i bloused for 22 gms, and then my usual 10 for my eggs (total of 32). i didn’t spike at all. my BGs were nice and even. but now, after 3 hrs, my BGs are slowly going low ( 94 ; which is low for me if i am trending down from my fasting BG which was 127) . perhaps the next time i go for the coffee, i will try just adding for 21gms of carbs and see how that works. but, before i do that, i am interested in how todays experiment works out. i still have IOB, so i will see and let you know how it went.

I find it’s the caffiene in coffee that raises blood sugar. I had to switch over to decaffienated because of the heart attack and palpitations resulted from that. Caffiene makes the flutters worse. Decaffienated coffee does not raise blood sugar or affect my heart. And I drink it with creme and liguid splenda.

OK, this is totally baffling to me. i know that i already wrote that am coffee spikes my BG. but, this morning, i had my usual breakfast of 3 eggs and a C of coffee. no spike at all!! in fact, my BGs went down for a little bit until recovering back to normal ( 95 ). how on earth did this happen? do others out there experience the "only sometimes " effect of certain foods like coffee?

It probably is a combination of the Splenda (has malidxtrin, suclarose & dextrose in it - all sugars - small amounts but still sugars), half n half has milk which has carbs in it. Try stevia liquid form (pure stuff get at trader joes or health food store) and real cream (only .4 carbs per teaspoon - you use less and it tastes better) in your coffee. I now have no coffee spikes.

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I also had to switch to decaf as coffee caused a morning spike on top of my wonderful DP.
If I’m a bit low and don’t have time to eat I get a small cappuccino and it tides me over wonderfully. I have never sweetened my coffee.

This makes me wonder… If black coffee has pretty much zero carbs, but the caffine causes a spike… I wonder if it’s something people can build up a tolerance to? Just as if someone doesn’t drink a lot of caffine might get jittery from one cup of coffee, but someone who is used to it can drink several cups in a row with no jitters-- maybe the same concept might apply to BG too? Curious to know-- are those who are spiked by coffee the “once in a while” coffee drinkers? Or the rarely spotted without coffee cup in-hand type like me? Like I said I drink a lot of black coffee and rarely, if ever, have I thought it has had any effect on my bg.

Sam, coffee relaxes me and does not cause a spike in blood sugars. I’ve always drunk ground coffee with added full fat milk, no sugar or sweetener. If I can’t sleep well I will get up and make a cup of coffee and am asleep in no time.

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