I have recently had a significant improvement in acid reflux symptoms. The key for me was to just eat less.
I am not morbidly obese. I have a pretty small frame and am about 5 ft 6 in tall. My BMI before cutting my portion sizes down was on the upper end of the normal weight range (24.9).
I tend to be a fast eater, and I think that did me no favors.
It makes a lot of sense in retrospect. But when you're not obese, cutting your portion sizes is not the first thing that comes to mind as a method for improving health.