Low-proof alcoholic beverages and gastroesophageal reflux.

Previous studies have demonstrated an increased gastroesophageal reflux after the ingestion of high-proof alcoholic beverages in normal subjects. Data on gastroesophageal reflux with usual amounts of low-proof alcoholic beverages are not available. The effect of white wine (7.5% v/v, pH 3.2) and beer (7.0% v/v, pH 4.5) was compared with water, a nonalcoholic beverage of pH 3.2, and an ethanol solution (7.5% v/v, pH 7.6) using ambulatory pH measurement in healthy volunteers. The fraction of time at pH < 4 in the first hour after ingestion of 300 ml white wine (median 13.2%) was significantly increased compared with beer (3.6%; P < 0.01), water (0.9%; P < 0.001), ethanol (1.3%; P < 0.001), and the nonalcoholic beverage (0.9%; P < 0.05). Beer provoked significantly more gastroesophageal reflux than water (P < 0.01). It is concluded that white wine and beer induce gastroesophageal reflux, which is neither related to their ethanol content nor to their pH. The mechanism for this effect remains to be identified.