Bok choy is edible overnight without spoilage, but it is not recommended. After cooking, if the green vegetables are properly preserved (sealed, refrigerated storage, etc.), and there is no deterioration (odor, spoilage, surface plaque and other abnormalities), if you want to eat, you can eat. However, overnight brussels sprouts, can produce nitrites, and nitrites are carcinogens, is not good for the health of the organism. Secondly, after the green vegetables overnight, the microorganisms in them grow and multiply in large numbers, which can lead to gastrointestinal inflammation and cause diarrhea, vomiting and other symptoms after taking them. At the same time, overnight green vegetables, which contain some nutrients (such as vitamin C, anthocyanins, etc.) can be oxidized by the air, losing the original value. Therefore, green vegetables overnight can be eaten if there is no deterioration, but it is not recommended, and if there are uncomfortable symptoms after consumption, you should go to the local hospital.