Hello one and all-
I’m Type 1 & lactose intolerant, and I notice that when I have dairy I always tend to have high blood sugars hours later, even if I’ve initially taken insulin to cover the carbs. I suspect that it’s taking a longer time for my body to actually digest the dairy and so it’s giving me some kind of delayed effect. I’m not so great about knowing the physiology behind how all this stuff works, and I’m really just making observations based on what I’m eating and my BS readings, but does that make sense?
Can anyone (lactose intolerant or not) shed light on this for me, please? Am I totally off base here? Obviously, the ideal way to deal with this is to avoid dairy, but on those few occasions that I can’t or choose not to (I’m a sucker for cheese), how should I take insulin for this? I’m on MDI so I can’t technically do an extended or dual wave bolus, but I can take another shot later a few hours after I eat.
Any experience or thoughts or advice would be greatly appreciated. 
Does cheese raise your blood sugar too? I don’t need any insulin to cover cheese (almost no carbs…)
It does a little bit, but not as much as milk.
Lactose intolerance and milk allergies are two different things. Both can cause “wonky blood sugars.” Lactose intolerance is when you lack the required enzyme (lactase) to digest lactose. The symptoms are typically a huge amount of gastric distress as the lactose passes into your lower intestine where it is “fermented.” The result of this fermentation may also provide additional sources of blood glucose well after your meal. The reaction in your lower intestine may also cause higher blood sugars simply from the gastric action taking place. Lactose intolerance can also be caused by Celiac’s which damages your intestine affecting the production of lactase. I presume you don’t have gluten problems, but as a T1 it probably is worth keeping an eye out for it. If you take a lactase supplement and find your symptoms are relieved, then it is probably just that you have a lactose intolerance. A serving of milk contains 12g of lactose, while cheddar cheese only contains 0.02g. Not surprising that cheese is not so bad.
If you have a milk allergy, you would have a very different reaction, your blood sugar might rise quite high and remain elevated until the milk is out of your system. You might find you react as strongly to cheese as to milk.
My first suggestion might be to try lactase supplementation and see if that could help. If you have highly variable reactions to dairy products, you might find it very difficult to properly match an extended or dual wave bolus.
Thanks for the explanation of what’s going on after I put dairy in my mouth. I was pretty familiar with the gastric distress symptoms but not what was actually going on in my body, so thanks! I have not actually ever been tested for Celiac, but I actually have an endo appointment next week and I was planning on getting tested, just in case. Thanks for the info!
