A long-term study has determined that smoking and high salt intake contribute somehow to the development of acid reflux [stomach acid causing heartburn, belching, etc.]. Tea and alcohol, long thought to be responsible, have no identifiable effect on the disease.
Seems that nitrites in the stomach (from a salty diet) can cause an excess of nitric oxide–which, as we know, is good for relaxing blood vessels–also relaxes the muscle at the bottom of the gullet and thus encourages reflux. Astonishing what a single substance can do–both positive and negative–in our bodies. Apparently you can decrease your risk, though, by regularly eating fiber and exercising.
Geez, will they never run out of reasons for telling us to eat healthy and exercise?