Diabetic neuropathy is caused by

Diabetic neuropathy develops when diabetes damages nerves over time. High blood sugar can harm the small blood vessels that supply nerves, reducing their blood flow; it can also directly injure nerve cells. Thus, the best choice is inadequate blood supply to the nerves. Trauma, autoimmune attack, and compression can cause other types of nerve damage, but they are not the usual cause of diabetic neuropathy.

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