Creatine & Acetyl L Carnitine Energy Plus, 0.51 lb Is Vitamin C Safe with Kidney Disease? If you are like a lot of people, you may have never heard of carnitine but this important nutrient is critical for our body's ability to optimally burn fat required for energy. Herbal supplements may seem safe because they are natural, but for people with chronic kidney disease (CKD), they can pose serious risks. They may harm your kidneys, interact with medications, or increase