Whenever entering / exiting dimensions, certain mods that have the ability to change certain stats such as health and speed get messed up. These are the mods I'm using that seem to be affected:
https://minecraft.curseforge.com/projects/spice-of-life-carrot-edition?gameCategorySlug=mc-mods&projectID=277616 - The Spice of Life - Carrot Edition
https://minecraft.curseforge.com/projects/improvable-skills?gameCategorySlug=mc-mods&projectID=252902 - Improvable Skills 3

I am not certain what exactly causes this to happen, but I am positively certain that the way that we handle dimensional teleporting could be bugged in the area of "updating a player entity with its original properties."