consequently the supply of the air to the lungs is totally blocked off when this occurs it is called sleep apnea an apnea is defined as an absence of air flow for about 10 seconds or more a person with a typical case of sleep apnea has a blockage of breathing of about 10 to 60 seconds at a frequency of five times per hour despite the lack of oxygen the sleeping person is constantly trying to bring air into the lungs forcing a complete collapse of the tissues of the throat and causing a gasping or snoring type noise during this process the person will have a dangerous drop in blood pressure this situation can become potentially dangerous under normal circumstances the apnea is terminated by an arousal and for the most part is so brief it is hardly remembered the arousal increases the tone of the muscles in the throat and tongue thereby releasing the airway blockage and creating a loud grunt or snore this is usually followed by a period of rapid breathing and again a new apnea occurs obesity is another condition which can cause snoring obesity is occasioned by fatty deposits in the throat and a narrowing of the air passage as the tongue and uvula become enlarged with weight gain the airway in the throat is reduced which can exacerbate snoring a receding chin due to a poorly positioned jaw can also cause a reduction in airway size enlarged tonsils or adenoids in children can have the same reducing effect as they do.