Nausea, abdominal discomfort, and other gastrointestinal symptoms are commonly reported by individuals after drinking alcoholic beverages. The alcohol itself may cause gastrointestinal problems by affecting the gastric emptying process. Researchers at the University Hospital of Heidelberg at Mannheim in Germany conduced a systematic study of the effects of ethanol, alcoholic beverages, and the non-alcohol components of alcoholic beverages on the gastric emptying of solid meals in the human body, and the results suggest that alcohol rehab may improve gastrointestinal problems (Franke et. al., 2005).
The researchers recruited 16 fasting, healthy, male participants who received once weekly 300 ml of pure ethanol, beer, red wine, glucose, and water in a random order. The solutions were given with either a low-calorie or high-calorie solid meal. Real-time ultransonography was utilized to directly view the gastric emptying process. The researchers point out that ultrasonography is “simple, non-invasive, and does not entail radiation.” This allowed the researchers to repeat measurements on the same subjects with the different test solutions.
Result showed that the gastric half emptying time for a high-calorie meal was significantly prolonged with the ingestion of pure ethanol, beer, and red wine, as compared to water. Gastric half emptying time “corresponds to the interval between the end of the meal and the moment when antral area was reduced to 50% of the maximal antral area.” However, in the later, lag phase of gastric emptying, there was no significant difference between ethanol, beer, red wine, and water, but the ingestion of glucose with the meal prolonged the lag phase.
Compared to low-calorie meals, high-calorie meals results in a 2-fold prolongation of gastric half emptying time. However, the effects of the different solutions on gastric emptying times were similar for both low-calorie and high-calorie meals. Pure ethanol, beer, and red wine all prolonged gastric emptying. Further, the inhibitory effect of red wine (but not beer) is stronger than that of the corresponding pure ethanol concentration and amount. The researchers posit that red wine contains ingredients that further prolong gastric emptying. In summation, the inhibitory effect of ethanol and alcoholic beverages primarily affects the gastric emptying phase (without affecting the lag phase), and the inhibitory effect of ethanol and alcoholic beverages does not depend on the caloric content of the meal.
“Unlike pure ethanol solutions, alcoholic beverages such as beer and red wine contain a number of non-alcoholic ingredients which are osmotically and calorically effective and are, for example responsible for the stimulatory effects on the gastrin secretion,” the authors point out. “Therefore, the ultimate effect of alcoholic beverages on gastric emptying is the result of the interplay of the effects of ethanol itself and these non-alcoholic substances.”
Franke A, Nakchbandi IA, Schneider A, Harder H, Singer MV. The effect of ethanol and alcoholicbeverages on gastric emptying of solid meals in humans. Alcohol and Alcoholism. 2005; 40(3): 187-193.