Checking blood can detect a variety of diseases, such as viral hepatitis, diabetes, anemia, blood diseases and so on. 1. Viral Hepatitis: Many patients may be related to viral hepatitis after they have itchy skin, loss of appetite, generalized weakness, etc. It is recommended that patients should go to the hospital for blood test to determine whether it is caused by viral infection. It is recommended that patients go to the hospital in time through the blood test to determine whether the hepatitis is caused by viral infection, after diagnosis, under the guidance of the doctor, take antiviral drugs such as ribavirin to control the condition. 2. Diabetes mellitus: patients may have weight loss, excessive urination, drinking and other phenomena, mainly due to high blood glucose levels, the body can not make full use of the cause. It is recommended that the patient go to the hospital for blood test to clarify the blood sugar level; if necessary, the patient can take oral hypoglycemic drugs or insulin injection to control the condition under the doctor’s guidance. 3. Anemia: Some weak patients have anemia all year round, and the disease can be diagnosed through blood sampling. Anemia can be improved by blood replenishing drugs and foods containing iron, including iron fumarate and iron dextrose. 4. Blood diseases: acute leukemia, for example, can be diagnosed by blood sampling. The patient’s blood may show increased white blood cell count, peripheral blood smear can find primitive leukemia cells and decreased platelet count. 5. Others: It can also check whether the patient has high blood fat, whether there is hyperuricemia, renal insufficiency, abnormal thyroid function, electrolyte disorders, such as hyperkalemia, hypokalemia, hypernatremia, hyponatremia, hypercalcemia and so on. It is recommended to have regular medical checkups and seek timely medical treatment when abnormalities are found.