Food that should be packed: fruits, rice, beef, bean products, non-leafy vegetables, yogurt, etc.
Food that should not be packed: fish, seafood, leafy vegetables, twice-cooked pork, meat patties, fried rice.
The biggest disadvantage of packing a lunch is that after a morning, the nutritional value of the food is significantly lost, and it can also spoil easily in high temperatures. Therefore, it is best not to bring fish and seafood, as they are a breeding ground for E. coli and are most prone to spoilage.
All types of leafy vegetables contain varying amounts of nitrates. If overcooked or left for too long, not only will the vegetables turn yellow and taste bad, but the nitrates will also be converted by bacteria into toxic nitrites, causing varying degrees of poisoning symptoms in people.