Snoring causes

Snoring can be caused by a number of factors, such as the anatomy of your mouth and sinuses, alcohol consumption, allergies, a cold, and your weight.

When you doze off and progress from a light sleep to a deep sleep, the muscles in the roof of your mouth (soft palate), tongue and throat relax. The tissues in your throat can relax enough that they partially block your airway and vibrate.

The more narrowed your airway, the more forceful the airflow becomes. This increases tissue vibration, which causes your snoring to grow louder.

The following conditions can affect the airway and cause snoring:

Your mouth anatomy. Having a low, thick soft palate can narrow your airway. People who are overweight may have extra tissues in the back of their throats that may narrow their airways. Likewise, if the triangular piece of tissue hanging from the soft palate (uvula) is elongated, airflow can be obstructed and vibration increased.
Alcohol consumption. Snoring can also be brought on by consuming too much alcohol before bedtime. Alcohol relaxes throat muscles and decreases your natural defenses against airway obstruction.
Nasal problems. Chronic nasal congestion or a crooked partition between your nostrils (deviated nasal septum) may contribute to your snoring.
Sleep deprivation. Not getting enough sleep can lead to further throat relaxation.
Sleep position. Snoring is typically most frequent and loudest when sleeping on the back as gravity’s effect on the throat narrows the airway.
Risk factors
Risk factors that may contribute to snoring include:

Being a man. Men are more likely to snore or have sleep apnea than are women.
Being overweight. People who are overweight or obese are more likely to snore or have obstructive sleep apnea.
Having a narrow airway. Some people may have a long soft palate, or large tonsils or adenoids, which can narrow the airway and cause snoring.
Drinking alcohol. Alcohol relaxes your throat muscles, increasing the risk of snoring.
Having nasal problems. If you have a structural defect in your airway, such as a deviated septum, or your nose is chronically congested, your risk of snoring is greater.
Having a family history of snoring or obstructive sleep apnea. Heredity is a potential risk factor for OSA.
Complications
Habitual snoring may be more than just a nuisance. Aside from disrupting a bed partner’s sleep, if snoring is associated with OSA, you may be at risk for other complications, including:

Daytime sleepiness
Frequent frustration or anger
Difficulty concentrating
A greater risk of high blood pressure, heart conditions and stroke
An increased risk of behavior problems, such as aggression or learning problems, in children with OSA
An increased risk of motor vehicle accidents due to lack of sleep.