Leftovers are convenient, but not every food stays safe after sitting out or being reheated. Experts warn that some items can quickly develop bacteria or lose quality if handled improperly. Here are five foods that require extra care.

1. Rice
Cooked rice can grow bacteria called Bacillus cereus if left at room temperature too long. This bacteria produces toxins that “are not destroyed by reheating.” Rice should be refrigerated within one hour of cooking and reheated only once, until very hot. If it smells odd or feels slimy, throw it away.

2. Potatoes
Cooked potatoes, especially when wrapped in foil, can encourage the growth of Clostridium botulinum if left out. Moisture and limited oxygen create the right environment for bacteria. Cool potatoes quickly, refrigerate them in shallow containers, and never leave them out for more than two hours. Reheat thoroughly before eating.

3. Chicken
Reheating chicken is safe only if done properly. “The risk comes when it is not heated evenly.” Poultry may carry bacteria like Salmonella and Campylobacter, and microwaves often leave cold spots. Reheat on the stove or in the oven when possible, and make sure the internal temperature reaches 165°F (74°C). Avoid reheating more than once.

4. Eggs
Cooked eggs can develop harmful bacteria if left at room temperature. Reheating may also make them rubbery. Eat eggs right away when possible. If storing, refrigerate within two hours and reheat gently — or skip reheating.

5. Leafy Greens
Cooked greens like spinach or kale are safe if cooled quickly, but avoid leaving them warm for long periods. Reheating multiple times can also reduce nutrients. Refrigerate promptly and reheat only once, or enjoy them cold.

The key to food safety is proper cooling, storage, and thorough reheating. As experts advise:

“If the smell is off, the texture is strange, or your instincts say no — throw it out.”

Food poisoning is never worth the risk.