The Study continued...
All participants also reported any symptoms they had, such as euphoria, dizziness, or slurred speech.
The surgery patients had an average peak alcohol breath level of 0.08% -- enough to be declared drunk when driving a motor vehicle. The nonsurgery participants had a level of 0.05%.
The bypass patients took 108 minutes, on average, to normalize back to a zero breath level of alcohol; the breath levels of alcohol of the nonsurgery group returned to zero after 72 minutes.
Based on the levels and the time it took for them to normalize, the surgery patients should have had more or greater symptoms than the nonsurgery group. But surprisingly, "the symptoms were exactly the same," says Morton. The surgery patients' symptoms "should have been more pronounced because their peaks were higher and they took longer to normalize."
Interpretations of the Study
Based on the study findings, gastric bypass patients "are not metabolizing alcohol the same way and not feeling the same way [as the nonsurgery participants]," Morton tells WebMD.
The finding, he says, may explain why some experts have observed, and feared -- that those who undergo bypass surgery might experience "addiction transfer," in which they trade the addiction of binge eating, an issue for many gastric bypass surgery patients, for an alcohol addiction.
"This might account for some people becoming addicted to alcohol [after bypass surgery]," Morton tells WebMD. "They may have to drink more to get the same effect."
Physiologically, he says, there are explanations, too. The levels of a key enzyme for metabolizing alcohol, called alcohol dehydrogenase, decline because of the much smaller stomach size after gastric bypass surgery. Gastric bypass and other weight loss surgeries reduce the stomach's capacity to a few ounces. "This is probably why the alcohol peaks higher and stays higher," Morton says.
Why the patients aren't feeling more symptoms is not known, he adds.
"Alcohol is not calorie-free, of course," Morton reminds his patients. "A glass of wine has 125 calories. The other thing that happens when you drink alcohol is it relaxes you both outside and inside -- your esophagus and stomach also relax, and that allows you to eat more."
"I tell my patients to be careful with alcohol, and if they drink to do so at home or to have a designated driver," Morton says.