8 Things You Should Never Put in the Dishwasher (and Why)A dishwasher is convenient, but some items can be damaged by high heat, strong detergents, or powerful water jets. Here are common things that are better washed by hand:
- Cast iron pans
- Dishwashers can strip away the protective seasoning layer.
- This can lead to rust and a less effective cooking surface.
- Wooden utensils and cutting boards
- Heat and long exposure to water can cause wood to warp, crack, or split.
- Hand washing helps preserve the wood.
- Sharp knives
- Dishwasher cycles can dull blades over time.
- Knives can also damage dishwasher racks or become unsafe to handle.
- Crystal glassware
- Hot water and strong detergents may cause cloudiness, scratches, or damage to delicate crystal.
- Nonstick cookware
- Some dishwasher detergents and heat can gradually wear down nonstick coatings.
- Hand washing can help extend the coating’s life.
- Copper or brass items
- Dishwasher detergents can tarnish or discolor these metals.
- They often require gentle cleaning to maintain their finish.
- Insulated mugs and bottles
- Dishwasher heat may damage seals or insulation in some products.
- Water can sometimes get trapped between layers.
- Items with glued parts or delicate decorations
- Heat and water pressure can weaken adhesives or remove painted designs.
Tip: Always check the manufacturer’s instructions—some newer cookware and kitchen tools are labeled dishwasher-safe. If in doubt, gentle hand washing is usually the safest option.
