Which beverage components are known to relax the smooth muscle of the Lower Esophageal Sphincter (LES)?

Answer

Caffeine and Alcohol.

Both caffeine (from coffee or tea) and alcohol are specifically cited for relaxing the LES, which is the muscular barrier that normally keeps stomach contents contained.

Which beverage components are known to relax the smooth muscle of the Lower Esophageal Sphincter (LES)?
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