★★★★★
I am very prone to motion sickness. I cannot dive either because I cannot clear the pressure in my ear. I often has mild dizziness when changing position in my youth. But the vertigo started at the age of 35 and it was something much worse. I sometimes had to lean against a wall in order to not fall when standing up or just turning the head. It I was suffering a genetic problem common in my family.
It is by change that I stopped drinking coffee, just because there were no coffee shop in my new neighborhood. The vertigo stopped. I started coffee and coca-cola and the vertigo came back.
I repeated that cycle a good dozen times, and it reconfirmed every time the link between vertigo with cafeine
I saw 2 specialist (one was Otorhinolaryngology) who sweared there were no link between cafeine and vertigo. The Otorhinolaryngology said it was some loose crystals in the ear and not much could be done except some exercises like rotating the head.
Some web site call this similar dizziness BPPV (Benign Paroxysmal Positional Vertigo) syndrome and can be cure by the Epley maneuver. I never tested it though.
Now that I stopped definitively coffee and coca-cola, I seldom have vertigo and when I do have them, they are very mild.