My 1st post in this thread was 3 years ago and I have some comments based on my experience.
1st ... no effect on BG levels except they might go up if you give in to the hunger that a CBD/THC combo will give you ... and that drive to eat can be strong - so beware.
2nd ... If a CBD/THC combo is used to help with pain, it works well but will have the psychoactive side-effects that THC can give you. I only take CBD/THC in the evening to help me get some decent sleep anywhere from 2-3 hrs after taking it. I am not talking about smoking but ingesting. Smoking can be almost immediate. Many edibles are available that make it more acceptable. Just don't drive after taking anything with THC (or work with any tools/equipment that requires safety). I never use any edible or oil that has more than 5mg of THC. You can go as high as you want with CBD as there are no psychoactive effects.
NOTE: The psychoactive effects from using THC can last about 12 hrs so judge accordingly.
I also use a THC/CBD topical cream for aching muscles. Heavy on the THC and it acts locally on your muscles and does not affect you like ingesting or smoking. Works like a linament.
All that said, I do not know of any credible research or studies that show any effect on BG levels from any substance containing CBD or CBD/THC combinations.
Another caveat ... if a person has conditions like depression or anxiety then caution should be taken and only introduce anything with THC in it to a minimal test amount to see if it affects you in a negative way. It can be beneficial to these conditions but can also be the opposite.