Don't drink fruit juice as the process turns the fructose in fruit to glucose. When you eat food, your saliva sends messages to your brain which then sends messages to your pancreas to start producing insulin and then it can usually deal with fruit being turned into glucose through the chewing process but, if you drink fruit juices, you are just drinking glucose and it's basically the same as sweets etc. If you need to drink cranberry juice to combat cystitis, which diabetics can be prone to, use the no added sugar version. Lidl, Sainsbury and Tesco do their own brand no added sugar cranberry juice. Also beware of dried fruits because drying fruit turns the fructose into higher glucose levels within the fruit, dates are the exception, though. Three dates a day are actually good for you.