Feeling dizzy and lightheaded may be related to poor sleep quality, or it may be caused by high blood pressure, iron deficiency anemia and other reasons. 1. Poor sleep quality: If you have a heavy psychological burden, think too much in the near future, or often stay up too late, resulting in disorders of the biological clock, it may result in poor sleep quality, insufficient sleep time, and the brain can not get enough rest, resulting in dizziness and lightheadedness, accompanied by inattention, mental fatigue and other manifestations. 2. Hypertension: due to elevated blood pressure, resulting in increased pressure inside the cerebral blood vessels, which will make the patient feel dizzy and lightheaded, and may also be accompanied by headache, nausea and other symptoms. 3. Anemia: due to insufficient blood volume in the body, the number of red blood cells in the blood decreases, and the oxygen content of the blood decreases, resulting in cerebral ischemia and hypoxia, which may cause dizziness and faintness, and may be accompanied by weakness, poor appetite and other manifestations. Feeling dizzy, may also be related to other factors, if the symptoms persist, you should seek medical advice as soon as possible, diagnose the cause, give targeted treatment.