"National Standard for Food Safety Standards for the Use of Food Additives" stipulates that nitrite is only allowed in cured and smoked meats and other products with trace residues, the limit is 30 milligrams per kilogram, and the residue of smoked ham shall not exceed 70 milligrams per kilogram. For non-intentionally added, naturally occurring nitrite, "National Standard for the Limitation of Pollutants in Food" stipulates that the limit is generally 3 to 5 milligrams per kilogram, and the limit for pickles is 20 milligrams per kilogram.

1. Eat as little as possible or do not eat cured, smoked, waxy meat, as well as pickled sauerkraut and other salted vegetables shortly after pickling (including pickles within 24 hours of pickling time).

2. Prohibit the consumption of rotten and spoiled vegetables or spoiled pickles.

3. In the acidic environment of the stomach, nitrite is prone to nitrosation reaction with amines, the decomposition products of amino acids, to produce carcinogenic N-nitroso compounds. Vitamin C, vitamin E has a certain role in blocking the nitrosation reaction, so you can eat some vitamin C-rich fresh fruits and vegetables, vitamin E-rich nuts in moderation.