The 2-hour rule

The rule

CDC puts the limit for perishable food at 2 hours out of the refrigerator, or 1 hour if the food is exposed to temperatures above 90 °F. It counts meat, seafood, dairy, cut fruit, some vegetables and cooked leftovers as perishable.¹

The FDA applies the same limits to groceries: raw meat, poultry, seafood, eggs and produce that needs refrigeration should not sit at room temperature for more than 2 hours, and the limit is 1 hour when the air is above 90 °F.²

Take-out and restaurant leftovers fall under the same rule. The FDA says that if you cannot get home within 2 hours after eating out, it is better not to ask for a doggie bag.²

When the clock starts

For cooked food, CDC starts counting when cooking ends, or when the food is taken out of an appliance that was keeping it at a safe temperature. Hot food does not need to cool on the counter first: CDC suggests dividing it into several clean, shallow containers and refrigerating it, and the FDA says putting hot food in the refrigerator does not harm the appliance.³¹²

Why 2 hours

At room temperature, the FDA says the bacteria that cause foodborne illness can double every 20 minutes. Nebraska Extension adds that food held at unsafe temperatures for more than 2 hours may pick up harmful bacteria that ordinary cooking and reheating do not destroy, and advises throwing out food left out longer than that.²⁴

Smell and looks are no guide. The FDA notes that food can make you very sick even when it does not look, smell or taste spoiled, because the bacteria that cause illness are different from the spoilage bacteria that make food go bad.⁵

After a power cut

The same 2 hours appears in the FDA advice for power cuts: food in a fridge that stayed at or below 40 °F, or that was above 40 °F for 2 hours or less, should be safe to eat.²