Human Beings can't bio-create their own vitamin C stores unlike most members of the animal the kingdom. For the 60 million pre-diabetics and millions diabetics, this is a huge issue. As a result of the fact that:
High blood sugar levels increase urinary losses of vitamin C.
References:
Will JC, Byers T. Does diabetes mellitus increase the requirement for vitamin C? Nutr Rev. 1996;54:193-202.
Peerapatdit T, Patchanans N, Likidlilid A, Poldee S, Sriratanasathavorn C. Plasma lipid peroxidation and antioxidiant nutrients in type 2 diabetic patients. J Med Assoc Thai. 2006;89 Suppl 5:S147-55.