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Why does black coffee raise my sugars?

A

alex200274

Member
Messages
19
Location
Bristol UK
Type of diabetes
Type 1
Treatment type
Insulin
Hello I’m a type 1 diabetic (22 yrs), and I have noticed in the last year for some reason coffee will cause high peaks in my sugars.

I’m drinking black filtered coffee. For breakfast I will usually have two cups, and depending if I’m at home or work I may have two more cups during the day. Oddly I’m finding that my sugar levels are getting higher about 20-30 minutes after drinking the cup, if I do not drink then they are fine.

If my coffee does not have milk and of course no sugar I'm assuming the caffeine is causing it to peak? I just don’t know why I have suddenly become sensitive, should one count coffee then as something as having carbs as part of their insulin regime?
 
Have you tried decaf for a while to check? Maybe that would desensitise you.
I often work in different homes and places and find that some folk's coffee affects me too (I drink it black).
Regards
Angie
 
Good point! And no I have not tried decaf.

Another point is some coffee types such as various brands, instant or filtered all seem to have various results. I'm not sure if there are additional additives to coffee that may cause sugars to rise.

Also I'm not sure if the caffiene causes a release of glucose in the system, can't find much research about this. However I asked my diabetic specialist in a recent check-up and she said only cause for sugars to rise would be the milk but I'm not taking that so she was sort of stumped on what to say.
 
I'm sure there is something in some of them, especially some of the expensive speciality ones.
I tried decaf a bit back as I seemed to be having the same issue. Concluded it was other sorts and I've settled for Nescafe Black Gold regular instant as don't like decaf and it seems fine so far.
Angie
 
On google I searched for 'caffeine blocks insulin' and quite a lot of results were returned. The majority of articles state that Type 1 diabetics should avoid caffeine as it makes insulin less responsive, causing sugars to rise.

I can't believe I never knew this or was never advised to avoid caffeine. I assume there must be a threshold one has to induce before it impacts your control, otherwise would one need to abstain from all forms of caffiene (including soft drinks etc)?

I'm guessing if my sugars are spiking due to coffee intake then assume this is a symptom/reaction that can only be remedied by not drinking coffee (caffeine)- which is depressing as I love coffee!!
 

Oh wow! That's interesting - I've only just taken up drinking coffee again after years of not drinking it. It's how I get my single cream down me every day and I didn't connect it with increased BS levels. So what you've discovered is that even if coffee has no sugar in it, no milk, no cream, just taken neat - it causes sugar levels to rise not because of sugar or carb content but because the caffeine blocks insulin. I wonder how many other foods there are that are not carb or sugar laden but nevertheless affect how our insulin works? :think:
 
Funny how all of sudden I'm finding quite a lot if info on the subject. Can't believe in 22 years of being diabetic and all my health visits I was never told that caffiene could cause issues with my blood sugar levels.

Link below:

http://www.livestrong.com/article/39878 ... -diabetes/

I also headroom the gym and sometimes a hypo can occur but also read caffiene can help reduce that prior to any strenuous excercise, never realised this....

'While in most circumstances caffeine should be used in moderation to prevent spikes in blood sugar, its effect on the body may be helpful in certain situations. Exercise can make blood sugar levels drop dangerously low. However, the American Diabetes Association, suggests that type one diabetics who take 5 mg of caffeine per kg of body weight half an hour before exercising may be able to prevent hypoglycemia or low blood sugar.

Caffeine stimulates the production of adrenaline, which in turn causes glucose to say in the bloodstream longer. At this stage much more research is needed to fully determine the benefits of caffeine before exercise'
 
Hi Alex!

That's really interesting. I have often had the suspicion that diet Coke spikes my BG as I often end up higher than I expected when I have a can of diet Coke. When I have the diet Coke after a meal (and therefore inject for the meal) I seem to end up higher than normal, but when I drink the diet Coke on its own (i.e. no meal and no jab) I seem to be fine.

I was wondering whether the sweetner was causing it, or perhaps the fact it makes me feel full (i.e. Bernstein's Chinese Takeaway theory) or whether I was just imagining it. I had never even considered the caffeine. I'll pay more attention now when i have diet Coke to try to track what my BGs are doing. I rarely drink coffee, but I do drink quite a bit of black Earl Grey tea and this doesn't have the same effect.

Smidge
 
In Gary Scheiners book Think Like A Pancreas he discusses the impact of Caffeine on bg, he says normal consumption of caffeine will have little effect on bg but energy drinks, strongly brewed coffee and caffiene pills may make an impact.

I've never noticed coffee or tea effecting my bg when I drank caffeinated drinks, if you are concerned then switch to decaffeinated drinks.
 
Hi Alex

Coffee does raise blood sugars and it can be by quiet a lot depending on the individuals own response to it, I use a coffee to treat a mild Hypo and it works great for me.

The reason why it raises Blood Glucose is that the Caffeine causes an instant Adrenal response, this is one of the glands in the body which is responsible for the "flight or Fight" response. So when we drink coffee a hormone called Cortisol an Adrenalin is released into the blood stream which will have a slight blocking effect on circulating insulin take up. Also Cortisol and adrenalin and other fight of flight hormones released by the Adrenal glands will have a short term sudden impact on raising Blood Glucose, this is the main reason for a raise in Blood Sugar.

Try cream with your coffee instead of milk ,the cream slows down the absorption of the Coffee/Caffeine so slows down the Adrenal response...less rise in BG, though it does all depend on the individuals Adrenal response, though worth a try!
 
Thanks for the response, I guess for me the issue was the sudden change in the last month where as the past 20 years or so caffeine hadn't been an issue with my sugar levels.

I have also recently found sometimes that diet soft drinks has spiked my sugars slightly and often wondered if I accidentally drank a normal soft drink, but perhaps as mentioned above by smidges experience it could be related to the caffeine.

Perhaps I have just suddenly become extra sensitive to caffeine, will have to look into it and start taking the decaf approach.
 
Wow! I just realised this is happening to me. Couldn't work out why high sugars occur after strong (white) mug of coffee is consumed. Was looking at everything else that could explain it but not the coffee. I'm a big drinker of filter coffee. This is a real eye opener. More so because people are reporting similiar results.In spite of less robust research available it's what people are reporting that catches my eye the most. Thanks for the info. Very useful.
 
Well thats me screwed! I can't even begin to function till my second dissolve-the-spoon-strength double espresso is finished.


Sent from the Diabetes Forum App
 
Yup. Coffee is (one of) my vices. Love it. Can guzzle it. Recently I got tired of trying to achieve perfect control. So many variables to juggle: physiology, insulin action, temperature ( in high temps apparently insulin can effect greater and drop sugars - my experience in 38 degrees C in Germany), absorption of food, exercise occurring etc. Been type 1 for approx 44 years. Some days it's tempting to throw the towel in and "live", not doing anything mad, just not obsessing. Coffee stays on the list of "things to enjoy" !!!!!!!!
 
I thought I would try this, as last week I had to visit a ophthalmic specialist was I had a problem with my eyes, it turns out that is was fatty/surgery growths behind the retina. I check my sugar level and it was 18 and as a heavy coffee drinker approx. 6-8 mugs a day it was a try, my sugar has been falling approx by 1 per day, this morning I was at 15.00 and all I have had since then is 1 piece of toast with jam & no coffee, when I rechecked 4 hours later it had fallen to 12.2.

I am staying off the coffee until Saturday, then restart to see what happens....
 
Type 1 since 1991, pump therapy since 2010 and have this year noticed my bg rising after black coffee. I’d always assumed that it was the sweeteners. I mentioned the rise to one of the DSN’s at The hospital last week and she had no idea.
Can’t believe none of the clinicians I’ve seen over the past 28 years have mentioned the possibility that caffeine can adversely affect bg.
 
Just noticed that this thread is nearly 7 years old!

I have been chasing a morning rise in BG made worse by exercise.
I considered coffee but tried decaf and it didn't seem to make a difference.

Time for another Libre and some testing!
 

Hello! I don't have any advice, but I've found this as well - good to know I'm not going mad
 
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