Seeds work a bit different in Remixed Pixel Dungeon. The main difference from the original game is that you can eat them. You will gain buffs from the seeds as soon as you eat one of them. Note that there is no general warrior health regeneration mechanic from eating seeds.
Seeds are collectible items that can be planted in the dungeon to grow various useful plants. They play an important role in the game's alchemy and farming systems.
Here are all the effects you can gain, for eating different kinds of seeds:
Collecting and properly using seeds is an important part of the game's resource management and can provide significant advantages to careful players.