When you log off and then log back on the health bar is stable. But, when do start moving, the health bar goes all the way down to death. You cannot drink potions or use bandages to stop the bar from dropping. This has happened to me 100% of the time so before I log off, I take everything off and put it in a chest but it's really a pain to do that.
Are you sure you are not affected by corruption? If you are too near an alter, then what you are explaining could be the reason?
Look at the Action, in-game, to see if you are affected by something, like corruption?
If it is corruption, then you'll need to sacrifice faction shards to the alter.
Must admit, it is not always it is working. so if the alter is the reason, then tear down your alter and move it more away from your base.
Og stay in your base and die. Many times, when you'll get back, the affect will be gone.
Good luck with this.
PS: If it is not an alter too near, please explain a little more?
It's not an alter problem as I don't even have one. I have no corruption or any other afflictions. When I log off, I'm fine. When I log back in, im fine until I start doing something like either opening a chest, or mining etc. Any movement triggers it and the health bar always goes to zero. It happens 100% of the time so I think it's an unknown bug.
If it is not an alter problem and you are not affected by anything else, then I have no clue why you are experiencing this..
I have never had that and I haven't heard of other players, who are experiencing the same as you.
Can you please report it in-game? There is an option where you can do so?
Good luck with this, I hope it can be solved for you.