Low blood pressure, also known as diastolic blood pressure, is normal if it is 68mmHg. According to the latest ninth edition of the textbook of internal medicine, for the diagnostic criteria of hypertension, the normal range of diastolic blood pressure should be less than 80mmHg. Therefore, if the low blood pressure, that is, the diastolic blood pressure, is 68mmHg, it is normal blood pressure. In actual clinical practice, if the diastolic blood pressure is greater than 65mmHg and less than 80mmHg, it is the most ideal diastolic blood pressure range. However, sometimes blood pressure is affected by many factors, such as age and weight. The older you are, the more you weigh, and the higher your diastolic blood pressure will be. Therefore, in order to maintain the blood pressure in such an ideal state, we must pay attention to weight control in daily life, as well as low-salt and low-fat diet.