Sushi can be eaten overnight. In fact, overnight sushi can be eaten hot and will not cause any discomfort. It's just that sushi that can't be eaten that day should be kept in the refrigerator for refrigeration, and it can be eaten when it is taken out and heated the next day. However, due to the overnight stay, the seaweed outside the sushi will soften, and the rice will not be chewy after refrigeration, and there may be some fishy smell. So overnight sushi can be heated, but the taste is greatly reduced.