Hard to tell because I did a few things at the same time. I think it has done something. Outside of my rebound reflux last year, which was as bad as my original reflux, if I have an episode now due to non-compliance with diet or bending down it is easily managed by popping an antacid in my mouth or taking a teaspoon of Gaviscon Advance or some water with baking soda. BUT, I am doing the low acid, low fat diet more faithfully, AND I am using filtered water with pH balancer drops. My throat also isn't sore all the time as it used to be, and I can more easily talk/sing without coughing. I do have a large hiatal hernia so I am quite pleased and amazed at the progress without a PPI. Because of the HH, I cannot dismiss the effects of the exercise with the mouthguard, even though it isn't exactly like the Iqoro. The mouthguard cost about $10 so even if it didn't work I wouldn't have been out much money, just effort. I can't say I would be in the same place without the diet change though.