What should be done with food that has been cooked but then left out overnight?

In the context of food safety, when food has been cooked and then left out overnight, the safest action is to discard it. This is based on the understanding of the "danger zone" for food—the temperature range between 40°F and 140°F, where bacteria can multiply rapidly. If food is left at room temperature for more than two hours, especially overnight, it is at a high risk of bacterial growth, leading to potential foodborne illnesses.

Even if the food appears to be okay or smells fine, harmful bacteria such as Salmonella or E. coli may still be present and can cause serious health issues. Reheating the food does not guarantee that it is safe to eat, as some bacteria can produce toxins that are heat-stable and will not be eliminated by cooking. Similarly, checking for spoilage does not ensure safety, as many bacteria do not affect the look or smell of food. Using the food for meal prep the next day also poses significant health risks and is not advisable.

Therefore, the safest and most responsible choice is to discard any food that has been left out overnight to protect against foodborne illness.