I saw on this popular website (http://www.livestrong.com/article/345573-how-to-relieve-the-feeling-of-overeating/) and other sites as well, a recommendation to take an antacid for overeating. But isn't that the opposite of what you would want to do?
You would want more stomach acid to help digest the food, not less. For heartburn yes an antacid makes sense but simply overeating not.
In medicine, upset stomach, bloating, discomfort or pain in the belly as well as feeling full quickly when eating is often referred as functional dyspepsia (FD). Although functional dyspepsia can be present without overeating, FD can be precipitated by rapid eating and overeating.
Several studies have shown that delayed gastric emptying and gastric hypersensitivity to acid or distension are involved in the pathogenesis of functional dyspepsia.
What is the role of antacids in symptoms of FD or overeating?
The exact role of acids in gastric motility has still to be defined. Current evidence suggest that gastric protons lead to the release of mediators (from the upper small intestine), which activate neuronal systems involved in controlling gastric motility. Additionally, high concentrations of acid are associated with increased fundic tone and impaired sensation to distension of the fundus. It is therefore possible that antacids, in particular proton pomp inhibitors (PPI), may reduce postprandial symptoms by modulating the effect of protons (acids) on gastric motility.
Interestingly, in 2006, a pilot study conducted among 12 healthy volunteers, showed that the administration of a PPI (20 mg bid for 2 days) reduced postprandial symptoms 30 min after ingestion of a small test meal. Other studies have reported that H2RA (Histamine H2 Antagonist) reduce intragastric volume and therefore lead to a reduction in postprandial fullness.
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