If the snoring is louder than 60dB, which prevents the passage of respiratory airflow in the upper airway, affects the rest of people in the same room or causes annoyance to others, it is called snoring. It is characterized by snoring of varying degrees at night, but the AHI is <5 times/hour, and there are no symptoms during the day. The light snoring (simple type) does not cause obvious hypoxia symptoms; the heavy snoring (breath-holding type) can be up to 80dB or more, and can be accompanied by different degrees of hypoxia symptoms, this kind of snoring is synonymous with obstructive sleep apnea syndrome, because snoring is a very prominent symptom of obstructive sleep apnea syndrome. Snoring occurs from the epiglottis to the nasopharynx without the hard support of the collapsed parts of the airway, including: soft palate, uvula, tonsils, palatal arches, the root of the tongue, the pharyngeal muscles and mucosa. Obese people have excess fat accumulation, increasing the burden on the respiratory and circulatory systems, and low muscle tone after sleep, thus narrowing the pharyngeal cavity and making it easier to snore.