This is another classic clickbait headline, but the idea behind it is actually useful: some items really can get damaged in a dishwasher because of high heat, strong detergent, and water pressure.
Here are 8 things you generally shouldn’t wash in the dishwasher (and why):
1. Wooden items (cutting boards, spoons)
- Water + heat can cause cracking, warping, and splitting.
2. Non-stick pans
- Dishwasher detergents can damage the coating over time.
3. Cast iron cookware
- It strips seasoning and can cause rust.
4. Sharp knives (chef’s knives)
- Heat and movement dull the blade quickly.
5. Crystal or delicate glassware
- Can become cloudy or crack due to heat and detergent.
6. Insulated travel mugs/bottles
- Can damage vacuum seals and reduce insulation.
7. Copper or brass items
- May tarnish or discolor in the dishwasher.
8. Certain plastics (not dishwasher-safe ones)
- Can warp or leach chemicals if not heat-rated.
Simple rule of thumb:
If it’s wood, sharp, delicate, non-stick, or sealed/insulated, it’s safer to wash by hand.
If you want, I can turn this into a quick “safe vs unsafe dishwasher” cheat sheet so you don’t have to guess each time.
