This patient support community is for questions related to juvenile diabetes including celiac disease, depression, diabetic complications, hyperglycemia / diabetic keto-acidosis, hypoglycemia, islet cell transplantation, nutritional issues, parenting a diabetic child, pregnancy, pump therapy, school issues, and teens with diabetes.
I think that your own BG tests will reveal how much grape juice & other highly concentrated sugars you can handle while staying within your target BG ranges. I can't say that I've noticed much of difference between having 15-30 carbo grams from, say honey or juice or other natural/healthy sources or getting the same amount from a small pile of jelly beans (all refined sugar). I don't eat much of either group, and would look to them to help treat low or -- perhaps a small amount for a treat.
Each of us is on a customized treatment plan that includes not only carbos, but also exercise, meds, and insulin. How we handle certain foods seems to vary widely, too. I know DMers who can't eat pasta, for example, without a signficant spike in their BG. Others do fine with pasta (preparation matters) but have trouble with potatoes.
This sure isn't easy!