8 Things You Absolutely Should Not Put in a Dishwasher (And Why)

High heat and prolonged exposure to water can cause wood to:

Warp
Crack
Split
Lose its finish
Wash wooden items by hand and allow them to air dry completely.

5. Nonstick Cookware
Although some manufacturers label nonstick pans as dishwasher-safe, frequent dishwasher use can gradually wear down the nonstick coating.

Hand washing with a soft sponge is usually the safest choice.

6. Insulated Travel Mugs
Vacuum-insulated mugs often contain sealed air chambers.

High dishwasher temperatures may damage the seal, reducing the mug’s ability to keep drinks hot or cold.

Check the manufacturer’s instructions before placing them in the dishwasher.

7. Copper and Aluminum Cookware
Harsh dishwasher detergents can discolor these metals.

You may notice:

Dull finishes
Dark stains
Oxidation
Loss of shine
Hand washing helps preserve their appearance.

8. Antique or Hand-Painted Dishes
Decorative finishes and painted designs can fade or peel after repeated dishwasher cycles.

Family heirlooms and handmade ceramics are usually safest when washed gently by hand.

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