The normal blood pressure for a 50 year old man is 120/80mmHg. Blood pressure usually refers to the arterial pressure in the body circulation, and a blood pressure greater than 140/90mmHg is diagnostic of hypertension, while a blood pressure less than 90/60mmHg is diagnostic of hypotension. The normal range of blood pressure varies with age. For example, the normal blood pressure for an adult before the age of 35 is about 115/75 mmHg, the normal range of blood pressure between the ages of 35 and 65 is about 120/80 mmHg, and after the age of 65, a blood pressure of about 140/90 mmHg is acceptable. Blood pressure control is not only related to age, but also to whether people suffer from diseases that can affect blood pressure. Nephritis, renal vascular disease, diabetes mellitus, hyperlipidemia, or elevated cranial pressure can increase blood pressure, for example, for diabetic patients the normal blood pressure is below 130/80mmHg.