Made a mod for my girlfriend @Kat called Gumobtainium - it adds two items, Gumobtainium and Gumbium. The former can be used to give yourself "gum hearts" that absorb any amount of damage, and regenerate after a few seconds, and the latter locks your hunger to be at least half full. They're made with weird methods specific to the mod.

GitHub: https://github.com/unascribed/Gumobtainium

CurseForge: https://minecraft.curseforge.com/projects/gumobtanium (still waiting for approval at the time of posting)