A funny thing happens when

…I eat foods I’m intolerant to. I have celiac disease, and when I accidentally eat gluten, my BG drops during the initial exposure period (12-24hrs). Because of CD, I’m also intolerant of dairy, and tonight I ate something that apparently contained enough trace amounts to cause a reaction - 30g carbs (2 cookies and a handful of berries) two hours ago, and I have not bolused anything. Can’t say I recommend this approach to a flatline, but it’s been really interesting to see the effect on my BG when my digestive system is thrown out of whack.

I know some of the other members here have food issues. Do you notice effects on your blood sugar levels directly related to exposure to foods you’re allergic/intolerant to?


If I’m having a true IgE-mediated allergic reaction (itching, hives, wheezing, and so on), I don’t notice much impact on my blood sugar, even thoguh my stomach might get upset as part of the reaction. Part of the reason may be that I’ve never really paid much attention to my blood sugar during such reactions. Or maybe it’s adrenaline and other hormones that get released in response to the reaction.

I used to have reactions several years ago where I’d wake up shortly after going to bed with an extremely upset stomach, acid reflux type symptoms, my heart racing, feeling flushed, and with my blood sugar crashing (but usually not yet low, though it would inevitably get there) on my CGM. I figure these must have been some sort of delayed allergic reaction, because sometimes my blood pressure would be low (for me) and I’d feel dizzy and my vision would get spots if I wasn’t lying down. This type of thing still happens occasionally, but has mostly disappeared since I stopped eating out (most happened on nights I ate out).

I have noticed that many of the times I have an upset stomach, regardless of whether it’s caused by an allergic reaction or something else, my blood sugar crashes. I think it’s likely because the body isn’t absorbing whatever food was eaten.


Thanks for sharing. I just think it’s fascinating to see such a clear picture of your body not actually digesting what you put in it. It’s so odd (and a little depressing), but fascinating nonetheless. Distracts from the misery part a little bit, ha!


Do you get a delayed peak later?

This reminds me of the several discussions we have had about using alcohol side effects to control BG…

LOL I don’t think it helped that I did have wine with dinner last night, too. Or, I guess it did help with the flatline side of things.


Nope, usually not unless I over-treat the low.


… we take snacks with well known numbers of carbs to correct a mild low.

19 times out of 20, the effect is more or less what we expect. But, the 20th time, it appears to cause a giant peak, the effect of which is 5x to 10x greater than it should be.

At first we thought the peaks were coincidences. But now we are certain that they are not: it happens too often, possibly every couple of weeks.

Does it ever happen to you?

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Yes, though the only times I can think of it happening are times when I’ve eaten spaghetti and had an odd delayed 2nd rise. Sometimes, not all the time, I’ll eat spaghetti and dip down into the 50s/60s after bolusing (Afrezza), correct it with just 2-4 carbs (I’m very carb sensitive when low), and then have a dramatic rise from both that 2nd meal rise and the correction added to it. Is it possible he’s rising from something he’s eaten earlier that maybe hadn’t fully hit yet?

I went out to eat for my bday w coworkers last year. Ordered chicken tacos. Felt sick for the next few hours. Went home and bolused for a small bowl of cereal/milk. It never spiked my blood sugar…I actually tanked. I had to struggle through juice for an hour or two to stay level. Then I started puking. I think it was food poisoning from lunch. Cereal/milk always spikes me…except during oncoming puking! Happy birthday to me!