I am a type 1.5 diabetic so I eat a very low carb high protein diet to normalize my blood sugars, rather than taking insulin.

It is correct that you need to consume energy on the bike, but it is not correct that carbs are the only fuel source you can use.

I have trained my body to work on protein and fat (i.e. it takes some time to adapt). On the bike, I drink shakes made from Jay Robb's Whey Protein Powder that I buy at our HEB Central Market. The container gives this link JayRobb.com. It is flavored with cocoa and stevia, and contains electrolytes. I make two large bottles with 1.5 scoops per bottle for a 3-4 hour ride. At the rest stop I fill what is gone with ice and continue drinking. I'll also munch some almonds at the rest stop, and as needed on the bike. On a longer ride (like a century) I might add a couple hard boiled eggs, and carry more powder to make more shakes as needed.