This is also an excellent, well-researched article that contains suggestions on supplementation for protecting your hearing and tinnitus: Hearing Loss and Tinnitus - Life Extension
Thanks for the link! It reminded me about aldosterone. In this forum there are quite info about it: Alternative treatment for hearing loss and Meniere's disease? New Drug Under Development to Prevent Age-Related Hearing Loss Aldosterone From the info above it seems that with the age aldosterone levels could decrease and this could impact hearing or even to cause hydrops. I checked some private laboratories, there is a possibility to check aldosterone levels. The test is cheap and I think it is worth to rule out low aldosterone levels.
There is also research which shows aldosterone may closely related to endolymphatic hydrops and Meniere's disease. This hormone regulates Sodium and Potassium activity in the inner ear. The strial Na/K-ATPase activation by aldosterone may result in an increased secretion of potassium ions in the endolymphatic compartment and an overproduction of endolymph. This may contribute to the development of an endolymphatic hydrops, as seen in Menière’s disease.