Yes, that sleep study seems a bit… um… financially profitable for the providers, though it is a common recommendation. You already know your son has a problem and where it’s coming from. It’s pretty common and not much of a mystery. The study does look to see whether there are other sources of breathing problems, but the other main source is obesity. You probably can tell yourself whether he has that problem. The sleep test could occur on one of his worst nights or one of his best nights, so it can’t fully tell how “bad” the apnea is, but you can probably tell pretty well yourself; after all, it is you who diagnosed it in the first place. The test also won't provide a lot in terms of deciding how to handle the situation. Even if they detected no apnea, it wouldn’t be appropriate to just ignore the whole situation, and if they determine there is another breathing problem, they typically wish to target the tonsils with surgery too. They already know what the medical options are… surgery, chronic medication, a continuous positive airway pressure (CPAP) device, or an apnea alarm. Basically, you know that you are ready to try doing something, but you’re not ready for surgery.
Spend plenty of time observing his sleep, (is there anything more beautiful anyway?) on several different nights when he is snoring. If you ever see any blueness to his lips or fingernails, then there is concern.
You can always have surgery later (and you probably won’t), so it makes sense to try to correct the cause first. Likely, if something is annoying his tonsil tissues, it’s also affecting other parts of his health to some degree. If, in the mean time, you have worry about his breathing, the CPAP or alarm are viable options to bring peace of mind, and maybe a more useful employ of your money. I’m not saying you need either of these though. I do expect that, with enough sleuthing, you’ll have fair success in improving his snoring, and then he’ll also grow into the size of his tonsils and adenoids some.
Tonsils are immune organs and, as you know, allergies are the chief cause of chronic inflammation in the tonsils. At your son’s age, food allergies are the more common cause. Usually if there are airborne allergies, he should have some sniffling, sneezing, or coughing, but there are those who are only affected in limited ways by airborne allergies. The same goes for foods. Do watch his symptoms in terms of environmental things things he’s exposed to during the days… a trip to the mall (perfumes, fabric treatments, scented candles), a petting zoo, eucalyptus trees, etc. If there’s anything you suspect in terms of environment, try either exposing him well to see if he snores worse, or try removing it from his environment to see if he improves. Second hand smoke exposure can definitely inflame tonsils. If you have a pet, she might want to take a little vacation away. Vacuum and dust well after she’s gone, and see if your son improves. A Honeywell or other HEPA airfilter in the bedroom and one in the living room might be a good idea in any case. You can even read up about dust mites. There are useful covers available for mattresses and pillows. If either parent has allergies, you can suspect your son may as well.
As for foods, you are right again; milk is the most common offender. It would certainly be the place to start. You need to go for 100% avoidance of any whey, casein, milk protein, butter, cream, etc. You will need to read labels well, especially with breads and any kind of ready-made products. Since tonsillitis and its resultant snoring aren’t always as quick to show improvement as some other symptoms may be, if you aren’t getting clear results, you may want to try a day of lots of dairy, after maybe some 7 days without any. A distinct worsening will give you a clear answer. Of course, there could be more than one food bothering him and if you don’t find them all, you may not see any improvement with reducing just one food. If milk elimination doesn’t give you answers, you’ll need to do a more complete elimination diet. If your son had colic, rashes, or diarrhea bouts, as a baby, you may suspect food intolerance more.
When the tonsils are regularly inflamed from allergies, they do provide some breeding ground for bacteria, and these contribute to the enlargement. I’d want to work the bacterial angle too. Eating yogurt (maybe coconut or almond based), fermented foods, and other foods containing probiotics, may give some benefit. I’d go for these rather than probiotic supplements, as we want them to linger in the mouth a while and pass right by the tonsils. Berries are antibacterial. Garlic and onions are great, as are all the Italian herbs (sounds like cheeseless pizza is in order). Any chance of getting 10 minutes of sun on those tonsils per day? Blue light is as useful as UV, so it can be any time of day.
Tradition once was to “paint” the tonsils with iodine. On first thought, this sounds awful, but actually, it’s not, and our foremothers may have known what they were doing. Tincture of iodine is half alcohol, which is nicely antibacterial, part water, and then 2.5% iodine, which is very antibacterial. Iodine is what’s added to iodized salt, occurs in our vegetables, especially seaweed, what our thyroid glands use, and something that certain health gurus today are saying we should be taking lots more of, so I wouldn’t consider it anything toxic. A Q-tip or a longer cotton swab is used to poke into the mouth and try to coat the tonsils a couple of times a day.
An alternative or additional product that I would try to paint with is something like Jason’s tea tree mouthwash. It has lots of great natural antibacterial ingredients. I think it could be pretty difficult to get a 3 year old to gargle, but not impossible. However, I had a gargle session with a dental hygienist when I did not believe that gargling would treat the back of my throat. We used the little dental dye tablets in water and gargled with them. There was no coloration in the backs of our throats and barely any on the tonsils, so I might not bother trying to teach a 3 year old to do so, but maybe we were just very bad garglers?
Salt also can help drain the tonsils and act antibacterial. Since I'm not so convinced about gargling (maybe you want to recreate my test -- we were looking for the pharynx and your son has a bigger, closer target), I've always just gone for eating salty foods, such as olives (also antibacterial), seaweed snacks, or salty popcorn.