I use a Camelbak Cortez hydration bladder for my water if I have room for it on deck. I'm often guilty of not hydrating even if I have water bottles around (probably has a little to do with not having a cup holder).
I'm not diabetic, but I'm required to maintain a strict low-sodium diet and I eat fig bars from Costco to keep me going between home-cooked meals. Can you eat jerky? I used to love to eat beef or salmon jerky while hiking, snowboarding, etc.