No, it is generally not safe to eat cooked vegetables that have been left out overnight. When cooked food is left at room temperature for an extended period, it provides an ideal environment for bacterial growth, which can lead to foodborne illnesses.
Bacteria such as Salmonella, E. coli, and Staphylococcus aureus can multiply rapidly in cooked vegetables left out at room temperature. These bacteria can cause food poisoning symptoms such as nausea, vomiting, diarrhea, and abdominal pain.
To ensure food safety, it is recommended to follow the "two-hour rule." Per this rule, perishable foods, including cooked vegetables, should not be left at room temperature for more than two hours. If the ambient temperature is above 90°F (32°C), the time limit decreases to one hour. After these time limits, the risk of bacterial contamination increases significantly.
To properly store cooked vegetables, you should refrigerate them within the recommended time frame. Place the vegetables in shallow containers and refrigerate them at a temperature below 40°F (4°C). This helps to cool them quickly and inhibits bacterial growth. If you are unsure about the safety of any food item, it is best to discard it to avoid the risk of foodborne illness.