The nitrate content in leafy vegetables, especially spinach and celery is very high. Nitrate is easily converted into nitrite which is harmful to health after repeated heating. Most leafy vegetables are not expensive, and people who give up after eating them will not feel too bad. If they need to prepare meals for the next day, it is recommended to choose vegetables such as roots, cauliflowers and melons, which have lower nitrite content than leafy vegetables.

Overnight vegetables not only destroy nutrition, but also produce pathogenic nitrite. This is because the longer the storage time, the more the nitrite content in vegetables increases. Fried vegetables and meat contain a lot of oil and salt, and the content of nitrite will increase sharply after long-term storage. Although nitrite does not directly cause cancer, it has certain health risks to the body.

Extended data

Pay attention to five points when eating overnight dishes:

1, classified storage, cold dishes, hot dishes, meat dishes and vegetarian dishes should be classified storage;

2. Vegetarian vegetables, especially leafy vegetables, contain a certain amount of nitrite, and the content will continue to increase after one night;

3. Unwanted dishes should be stored in lunch boxes in advance to avoid leaving leftovers and reduce cross-contamination;

4. When eating again, be sure to heat it thoroughly to achieve the purpose of sterilization;

5, must be placed in the refrigerator, avoid room temperature, overnight dishes look bad, abnormal smell must be thrown away.

People's Daily Online-Overnight dishes are harmful, so don't eat these overnight dishes again.

People's Daily Online-Five Reminders for Eating Overnight Dishes