The maximum daily intake of nitrate is related to the individual’s body weight, and the World Health Organization stipulates that the daily intake of nitrate should not be higher than 5mg/kg. Excessive intake of nitrate is harmful to the body, and nitrate will be reduced to nitrite when it enters the human body, and nitrite is extremely harmful to the human body. Nitrite can react with hemoglobin in the blood to form methemoglobin, which can’t transport oxygen normally and make people have the symptoms of hypoxia, and patients with mild symptoms will have dizziness, palpitations (rapid heartbeat, often accompanied by panic), and symptoms of vomiting. In severe cases there is a risk of hypoxic poisoning, where the patient has blurred consciousness, confusion, and respiratory distress, which may be life-threatening if not treated in time. Nitrite is a carcinogen, long-term intake is easy to induce the development of malignant tumors. In daily life, we should pay attention to avoid nitrate intake as much as possible.