The normal range of blood pressure in middle-aged people is as follows: systolic blood pressure between 90 and 140 mmHg, and diastolic blood pressure in the range of 60 to 90 mmHg. Without taking antihypertensive medication, hypertension can be recognized if the systolic blood pressure is ≥140mmHg and/or the diastolic blood pressure is ≥90mmHg on all three days of blood pressure measurements. Causes of hypertension include excessive alcohol consumption, prolonged stress and anxiety, high sodium and low potassium diets, etc. In addition, hypertension can be secondary to some renal diseases (e.g., glomerulonephritis, chronic pyelonephritis), endocrine disorders (e.g., pheochromocytoma, Cushing’s syndrome), and cranio-cerebral diseases (e.g., traumatic brain injuries, brain tumors). Hypotension is considered if the systolic blood pressure is found to be less than 90 mmHg and/or the diastolic blood pressure is less than 60 mmHg. Common causes of hypotension include postural hypotension, hypotension during pregnancy, etc. In addition, hypotension can be secondary to congenital heart disease, heart failure, thyroid disease and other diseases. It is recommended that middle-aged and elderly people bring their own sphygmomanometers and measure their blood pressure on a regular basis, so as to achieve early detection, early diagnosis and early treatment. People with high blood pressure and low blood pressure should follow the doctor’s instructions for targeted treatment, as well as active intervention in daily diet and lifestyle.