Young people suddenly dizziness to be alert to four kinds of disease is not accurate, can cause dizziness for a variety of reasons, including physiological factors and disease factors. Physiological factors include fatigue, mental stress and so on. Disease factors include infectious diseases, paroxysmal benign positional vertigo, ophthalmic diseases, intracranial diseases, anemia and so on. 1. Physiological factors: When excessive use of the brain will lead to lack of oxygen in the brain, which will have the symptom of dizziness. When the human body is overly nervous, there may be vascular spasm and dizziness, which will return to normal after rest. 2. Disease factors (1) Infectious diseases: for example, when upper respiratory tract infections, sinusitis develops, due to viral and bacterial attacks and the influence of endotoxin, patients may experience dizziness. (2) Paroxysmal benign positional vertigo: this disease is mainly due to the displacement of otoliths in the inner ear to the balance structure of the inner ear and dizziness symptoms. (3) Ophthalmogenic diseases: When suffering from myopia or wearing glasses of inappropriate prescription, dizziness symptoms may occur. (4) Intracranial diseases: when suffering from intracranial tumor, cerebral infarction, cerebral hemorrhage, dizziness symptoms can occur due to the cerebral blood vessels being blocked by tumor, thrombus, hematoma compression, and ischemia and hypoxia of brain tissue. (5) Anemia: The decrease of hemoglobin in the body leads to the decrease of oxygen-carrying capacity of the body, and dizziness is caused by ischemia and hypoxia in the brain. Young people should pay attention to sudden dizziness, when the symptoms continue to be unrelieved or progressive aggravation should be timely medical care, clear reasons, targeted treatment.