At present, the exact relation between diabetes and how it can affect hearing is not known. It’s theorised that glucose levels in the blood could cause damage to the tiny blood vessels of the inner ear, in a similar fashion to how diabetic nerve damage can affect the hands and feet, and other organs such as the eyes and kidneys. Our hearing mechanisms rely on specialised “hair cells”, which are very fragile and susceptible to changes in the environment, including the effect of increased glucose in blood.