6 Foods You Should Never Put Down Your Garbage Disposal, According To Plumbing Experts

I’m never quite sure what’s OK to toss in the garbage disposal. Those whirring and grinding noises make it seem like it could chew up anything, but some items can cause serious problems. I’ve learned this the hard way. I had to have my disposal replaced and the plumber lectured me about how few things should go down there.

It turns out that you can discard small amounts of fruit and vegetable scraps, ice, and most leftovers. “A few food scraps are fine for the disposal,” says Paul Abrams, public relations director for Roto-Rooter. “Where most people run into trouble is when they put too much into the disposal.”

The best way to prevent garbage disposal issues is by scraping plates and pots into the garbage can or compost, and leaving only the remaining food scraps for the garbage disposal to tackle. Here’s what else I found out about keeping your garbage disposal (and plumbing!) in tip-top shape.

The 6 Foods You Should Never Put in Your Garbage Disposal

It’s not just a matter of how much you put down the disposal, but what those items are. Here’s what the experts say should never be tossed in the disposal.

1. Eggshells: You may have heard that eggshells can sharpen the blades of your garbage disposal, but that’s not true. “They can get stuck between the moving parts of a garbage disposal and cause it to jam,” says Abrams. Even if your garbage disposal successfully grinds up eggshell pieces, that finely ground residue can clog pipes.
2. Coffee grounds: A sprinkling of coffee grounds likely won’t do much damage. However, if you throw your coffee pot leftovers in every day, they build up and can form into an unwieldy clump that is hard for the disposal to chop up and move along. 
3. Fats, oil, and grease: “You should never put oil, grease, or fat down the disposer, as these can cause clogs or interfere with the food waste disposer’s function,” says Chris Doscher, communications director for the Association of Home Appliance Manufacturers. Known as FOG, these materials are notorious for clogging pipes. Instead, pour cooking oil, meat fats, shortening, and other greasy items into a sealable container that can be tossed in the trash.
4. Fibrous or starchy foods: It’s OK to toss a little bit of starchy and fibrous food in the disposal, but save large amounts for the trash can. “Quantities of rice, pasta, and potato peels will break down into a sticky, starchy goo that sticks to pipe walls on the other side of the disposal and chokes drains,” says Abrams. This category also includes onion skins, carrot peels, and celery chunks. The long, stringy fibers in these foods can wrap around the mechanism.
5. Bones: Some people suggest that bones are good for the garbage disposal because they keep the blades sharp. Others say that small bones are OK, but stay away from big bones or tossing in an entire turkey carcass. However, Abrams says to avoid bones, no matter the type or quantity. It’s just not worth the risk to your disposal and your plumbing.
6. Nuts, pits, and seeds: Putting hard items like walnut shells and peach pits down your disposal means lots of wear and tear. In addition, when nuts are ground up they make a thick paste that can create a clog. It’s just easier to use the trash can. Avoid shellfish shells for the same reason.

How To Clean Your Garbage Disposal

If you cook often, you should clean your disposal and drain about every other week. “If you don’t use it often, allow your nose to guide you,” says Abrams. “If your disposal and kitchen drain are smelly, it’s time to clean.”

He suggests these easy ways to clean it:

• Baking soda + vinegar + ice cubes: Add one cup of baking soda, two cups of white vinegar, and two to three cups of ice cubes to the disposal. Let the disposal grind up the cubes and allow the mixture to sit for at least 15 minutes before rinsing with hot water.
• Lemon juice + salt + ice cubes: Add one cup of lemon juice, one-half cup of salt, and two to three cups of ice cubes to the disposal. Turn on the disposal and grind up the cubes, then allow it to sit for 15 minutes or more before rinsing with hot water.
• Dish soap + ice cubes: For an especially greasy disposal, pour in one-half cup of Dawn liquid dish soap and two to three cups of ice cubes. Grind up the ice cubes, then rinse with hot water.
• Fresh citrus: For a quick garbage disposal refresher when things start to smell funky, toss in orange or lemon wedges with the seeds removed. Grind them up and rinse with hot water.