If a high body mass index (BMI) is an issue, losing weight can reduce the severity of, but never completely eliminate, OSA. If snoring is present in the absence of OSA, this can in some cases be completely rectified with weight loss. People with a high BMI have more soft tissue in their upper airway, so when the tongue and soft palette fall back, the obstruction to airflow is greater due to the airway being narrower to begin with.
Alcohol or other sedatives such as sleeping medication relax the muscles more than usual and can contribute to OSA. Many people only snore on nights when they have consumed alcohol and those who snore regularly will be louder on such nights. Sleeping medications should be used on nights when you have particular issues getting to sleep and not relied on every night. Apart from the worsening of OSA symptoms, a reliance on sleeping pills will reduce their effectiveness.