Unfortunately, the sugar you need to prevent hypoglycemia is going to be sweet and have calories.  That's the nature of the beast...
I am finding that I do quite well snorfing down clif blocks during riding, and drinking water (or clif drink mix).  They don't give the huge blood glucose spike and crash.  
Maybe if you eat Blox, you would be better able to tolerate the brief burst of sweetness?  Then you could drink just water.
Have you worked with a nutritionist yet?  Mine was quite helpful.
				
			 
			
		 
			
				
			
			
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