Hi Keaka,
I am not a medical professional but a volunteer on this forum and a Type I
diabetic. From what I know diabetes can cause
impotence in men. It affects autonomic nerves, which go from your spinal cord to your lungs, heart, stomach, intestines, bladder, and sex organs. Men who have had diabetes for many years can be affected by the damage to these nerves, resulting in impotence.
The Joslin Diabetes Center website has some information on how to treat this condition.