Hey there,   I'm a Type 1 diabetic and hold 15 records in competitive powerlifting.   Creatine shouldn't have any impact on your blood sugar. Pay attention to your dosing, as you really don't need more than the 3 - 5 grams a day dose.   Creatine is actually something we eat and make on a regular basis already. You get tons of natural creatine when you eat meat, especiallly beef.   It benefits you after weightlifting because it allows the cells in your muscles to retain more water. The more water your cells retain, the more nutrients (food) they can absorb in order to help repair, heal and grow stronger.   You can check out my YouTubeChannel at www.youtube.com/user/gingervieira and my website at www.living-in-progress.com   Hope this is helpful!