Garbage disposals are designed to take a lot of abuse, but nowhere near what some people put them through. As magical as they seem, these powerful machines do have their limits—and if used improperly, you can do just as much damage to your plumbing with a disposal as you can without one.
Everyone knows that certain things don’t belong in a garbage disposal, but it’s surprisingly hard to get a straight answer about what exactly those things are. The easiest way to separate the things that can and cannot go down the disposal is to have a general idea of how they work.
Lots of people think that garbage disposals have spinning blades like a blender, but they’re actually closer to flat burr coffee grinder. As the motor turns, it forces food particles in the main disposal chamber through a series of holes around the perimeter, breaking them up into tiny particles. From there, the food flows into the wastewater pipe and on its merry way:
Ultimately, your garbage disposal is just a fancy front door to your kitchen sink: everything you put down it eventually ends up in your pipes, just in much smaller pieces. In order for a piece of food to go from the garbage disposal to the waste water treatment plant with no major detours along the way, it needs to be soft enough to pass through the grind holes and water-soluble enough to resist clogging. This covers most things you’d eat, but as always, there are some notable exceptions.