Alsa is spot on as usual
Not a lot to add.
Weight will not help, if he has a large neck size or put down fat around his neck it may be the cause of his snoring.
If he stops breathing during the night it may be a sign of Sleep Apnoea, if he does stop (pause) breathing it will develop into full blown Obstructive Sleep Apnoea. Get him to the GP.
Loosing weight will help but it is anything but easy.