4. Kidney Failure

Prolonged high blood sugar levels in diabetes causes damage to the kidneys over time. The kidneys serve as a filter, cleaning blood as it passes through these organs therefore damage to them could result in the build-up of waste inside our bodies, poisoning and killing us slowly. Kidney damage as a result of high blood sugar is called diabetic nephropathy, and the only way to know if you have it is through the constant monitoring of urine and blood. Diabetic nephropathy is the most common cause of kidney failure in the United States, and the only way to survive it is through expensive dialysis or a kidney transplant.