When forcing textures in servers, health and hunger bar textures are bugged, and replaced with the textures of chests and dispensers. When entering a single player world, or any other world in fact, after that, it will remain bugged like that. (With vanilla texture pack) The textures of the health bar change in single player however.
This was all done using a vanilla texture pack with the client, and gets bugged when being forced by a server.
See more related issues below.