How about buying a sealed bag of granola mix at the airport, one with lots of nuts, maybe some little pretzel sticks, m&ms (save those for the lows) (actually those dried fruits are loaded with sugar as well). Or else just a big bag of mixed nuts or shelled sunflower seeds?
I am also diabetic and Personally, my favorite carry on snack/lunch is a breakfast jack type of sandwich which I pick up at the airport ~ Very satisfying, good carb balance ~ protein in the egg, cheese and sausage, and tastes fine cold.
How about an orange or apple from the airport? keep the receipt so they can see that you purchased it there. I always take along some extra zip lock bags to keep my snacks fresh and when I have to toss them in my purse they don't make a mess.
Are you able to take a couple of cans of Glucerna? maybe along with your glucose medicine prescription it would be acceptable. It's worth a try, If not acceptable, you can just leave it at the terminal along with the other 'discards'. Who knows what they will end up serving you on the plane???? better to come prepared. If it's too heavy you can always tuck one in hubbys carry on bag. LOL
Wonder if they carry bottles of Propel at the airport? very tasty, and no sugar! You can buy pkgs of the single serving powder mix to take along with you in your checked bag for when you land. Just add to bottled water anywhere you go.
Be sure to take copies of any prescriptions you will be taking and all bottles of meds must now have the pharmacy prescription info printed on them. No loose, unmarked pills please. ( I pack my pill organizer separate and fill it when I arrive) I got a print out of all of my prescriptions from my pharmacist ( I added my drs names and phone #s) which I tucked in with my passport. I actually took all of my meds to the pharmacist and had some smaller bottles with prescription info on them before my trip so I didn't have to lug around that big ole bottle of my Metformin. LOL She counted out 50 pills and repackaged them for me into the smaller bottle. Such a wonderful service ~ got that from Target!!
I know you didn't ask about meds, but you know us diabetics, we gotta talk shop whenever we can. Just to encourage each other if nothing else!!!
Have a wonderful trip and good luck counting carbs in another country!
:loveya Hugs, Mariposa
PS, I'd love to hear more about how this all works out for you when you return.