Homocysteine is metabolically related to vitamin B12 deficiency, folic acid deficiency and other accompanying symptoms. 1. Symptoms related to vitamin B12 deficiency: Homocysteine can be converted to methionine or cysteine with the assistance of B vitamins. If B vitamins are deficient, pale skin, fatigue, fatigue, tingling sensation in the hands and feet, dizziness, mouth sores, and mood changes will occur. 2. Symptoms related to folic acid deficiency: homocysteine needs to receive methyl from tetrahydrofolate in order to be converted to other amino acids to complete the cycle. If folic acid deficiency is present, fatigue, mouth sores, swelling of the tongue, and developmental abnormalities can be seen. 3. Other accompanying symptoms: High homocysteine may also cause anemia, shortness of breath, arrhythmia, weight loss and other symptoms. It is recommended that the patient should consult a doctor in time and supplement folic acid or B vitamins according to the cause of the disease to achieve the therapeutic purpose.