Dr. Vanessa Coffman, alliance director at the U.S. nonprofit Stop Foodborne Illness, says perishable foods should not stay at room temperature for more than two hours in total. If the room is 32 °C or hotter, the limit is only one hour. The two‑hour limit includes all the time the food is out of the fridge, such as while serving or between meals.

Coffman adds that the risk of food‑borne illness grows when the time limit is passed, while reheating many times only changes taste, not safety. She recommends dividing leftovers into small portions and reheating only the amount you will eat, so you can keep track of the safe time.

She also advises that most refrigerated leftovers be eaten within three days or moved to the freezer. Homemade whipped cream and meat‑based gravies should be used within one day after refrigeration.