When going through nether portals with (potion) effects, the effect animations (particles, fire, visibility, additional hearts) are lost.

All effect animations on the player are lost when going through a portal:

• a burning player still burns, but shows no flames
• an invisible player seems to be visible again (but not for other players and mobs)
• potion effect animations won't show up

When something is eaten, the effect animations will show again