Many reasons can cause frequent dozing. First of all, the most common reason is poor sleep at night, too short sleep at night, sleep among the dreamy, sleep snoring, apnea, may affect the quality of sleep, for a long time, so that the biological clock is disturbed, daytime fatigue is always dozing, you should adjust the rest time, to ensure adequate sleep. In addition, poor nutrition, lack of protein in the body, lack of vitamins are also prone to daytime sleepiness dozing. This is because the body’s energy intake is insufficient, blood circulation is slow, the body will find ways to save energy, and sleep is the most energy-saving form, so it is easy to doze off. Obesity is also the cause of dozing, obesity can cause abnormal blood lipids, blood viscosity, slow blood flow, lack of blood supply to the brain, lack of oxygen will cause drowsiness, dozing. There are also psychological factors are also important reasons for dozing, because of the psychological needs such as escape from the status quo, mental depression, alternative in sleep from depression to get peace, in the strong psychological effect of daytime sleepiness. In addition, people also doze off in meetings, presentations and classes that do not interest them because of excessive nerve dissipation. Many diseases are closely related to dozing, such as anemia, diabetes, thyroid disease and even cerebral blood supply deficiency. Diabetes is more than twice as likely as others to have daytime dozing, and hypothyroidism is sleepy and weak due to a slowed basal metabolic rate. We have some relief from old dozing by cultivating a healthy lifestyle and treating the primary disease.