There are almost 100 sleep disorders recognized by the medical community. The sleep of a normal person contains as many as five sleep apneas per hour without any residual effects on health or daytime alertness. People with sleep apnea often do not fully wake up every time they experience an apnea event, so they may not complain of a 'sleep problem'. Identification/diagnosis of sleep apnea usually begins with complaints from the bed partner about loud snoring, and this prompts the sufferer to seek treatment. Sleep apnea can be treated a number of ways, depending on the severity of the problem, the physical construction of the nose and throat, and the weight of the patient. As sleep becomes less fragmented, daytime sleepiness diminishes; the heart and brain have a continuous flow of oxygen, and the patient's mood and personality return to normal.