How long can perishable food be left out at room temperature before it becomes unsafe to eat?

Perishable food can be safely left out at room temperature for a maximum of 2 hours. After this time frame, the risk of bacterial growth increases significantly. The "2-Hour Rule," as it is commonly known, is based on the understanding that bacteria can double in number every 20 minutes under favorable conditions, which is typically at temperatures between 40°F and 140°F (the "danger zone"). If food is left out beyond 2 hours, it should be discarded to prevent foodborne illness, as it may contain harmful bacteria that could lead to serious health issues if consumed. This guideline is crucial for maintaining food safety and preventing the growth of pathogens that thrive in warm environments.