I eliminated all foods, and added them back in one at a time. So I was able to find the two foods which caused a problem, wheat and dairy. Have now gone on a Vegan diet, it is working very well, I am breathing the best I have in my entire life.
Sometimes it seems you can beat sleep apnea. I had severe allergies (ragweed, various pollens) all my life. After many years of shots, I seemed to have this under control. However, I still could only breath through one nostril, I never breathed through both my entire life. Was falling asleep driving. Doctor sent me for the sleep study, had severe sleep apnea. Was given a machine with no humidifier, which was totally useless. Once I got the humidifier added, CPAP eliminated my daytime sleepiness. I wanted to make CPAP work better, tried prescription nasal spray, still only one nostril open. Went on an elimination diet searching for food allergies/sensitivities. Bingo. Eliminated two very common foods, and both my nostrils are now wide open with no blockage. I kept getting periodic sinus infections from the CPAP. So I have found, if I sleep on my side, and eliminate the two foods which bother me, I sleep very well without CPAP. Getting your nostrils open to where you can breathe well is essential if you are going to use CPAP or not.
Even when I was at normal weight, I still snored quite loudly. My kids made comments that they could hear me on the other side of the house with the door shut. Didn't have a sleep study until 3 years ago. I will have to have my friend and buddy "Snorf" for the rest of my life. Yes, CPAP is a pain in the butt...but it beats congestive heart failure, stroke, heart attack, pulmonary hypertension, high blood pressure and death.
If weight caused your apnea, losing it may get rid of it. If caused by abnormal throat structures, there is some success reported with surgery for those whose apnea is mild and maybe moderate. There are dental devices that also may help those with mild to moderate apnea. For those few whose throat is compromised by an inset jawbone, there is a very radical surgery for that too.
No matter what you choose, go into it knowing you may still need cpap therapy. I don't think there's many guarantees.