Under normal circumstances to breathe, mainly inhale the oxygen in the body to supply the various organs in the body, especially the oxygen supply to the brain, if the smoke is inhaled when smoking, oxygen deficiency, often can produce the symptoms of dizziness. There are two main cases: First, a large amount of smoke inhalation, smoking is relatively large, oxygen inhalation is reduced, a large amount of tobacco leads to a lack of oxygen in the body, especially the brain oxygen deficiency can produce acute dizziness. Second, long-term chronic mass smoking, this situation is often a relatively long smoking age, accompanied by 10, 20, or even 40 sticks of tobacco per day, tobacco can lead to vascular stenosis, vascular stenosis is an independent risk factor for smoking, can cause the narrowing of blood vessels in the brain, thus causing insufficient blood supply to the brain, resulting in dizziness. The harm of smoking is very serious, long-term heavy smoking can lead to dyslipidemia, increased thrombotic components in the blood, increased blood viscosity, vasoconstriction, increased blood pressure, thickening of the elasticity of the blood vessel wall, narrowing of the lumen, slow blood flow, and eventually the formation of various parts of the body vascular stenosis, especially the neck and brain blood vessels are more likely to be involved, if there is a narrowing of these parts of the blood vessels, easily lead to cerebral ischemia, especially If there is narrowing of the blood vessels in these areas, it is easy to lead to cerebral ischemia, especially ischemia of the posterior circulation of the brain causes more vertigo and dizziness.