Obesity is no longer considered just a case of over-eating and lack of self-control. It is acknowledged as a “chronic progressive disease resulting from multiple environmental and genetic factors” by various International and National scientific organizations, including the World Health Organization. The National Institute of Health recommends bariatric surgery as an effective treatment for weight-loss and maintenance of that weight-loss for people who are obese. However, it has been noted that those who’ve had gastric-bypass surgery are at increased risk for becoming sensitized to alcohol.
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Gastric-bypass surgery changes the way your stomach and intestines processes food to aid in rapid weight loss. Your stomach is divided into an upper and lower part. The upper part, which is the smaller of the two, is where the food consumed goes.  The middle part of the small intestine is then re-routed to connect to the upper stomach. This smaller stomach along with the shorter intestine limits the amount of food you eat and minimizes the number of calories absorbed by the body so that weight loss is rapid and, provided you follow post-operative directions, maintained over the long run.
It has been noticed that individuals are more susceptible to becoming sensitized to alcohol after gastric-bypass surgery, and possibly causing over-indulgence and alcoholism. There are two theories as to why this is so. It is the opinion of some professionals that increase in alcoholism amongst gastric-bypass surgery is caused by transferring the food addiction to an alcohol addiction. Indeed, studies have shown that those who were binge-eaters before the surgery are at a higher risk for alcoholism afterward.
Research has also shown that recipients of gastric-bypass surgery had a higher breath alcohol content, and it took longer for alcohol to leave their system after drinking. The study showed that after a single glass of wine their breath alcohol levels were over .08, which is the level you are legally allowed to drive with.  These findings are not found in one who has had gastric banding, another type of bariatric surgery in which a band is placed around the stomach to create a small pouch at the top. That type of surgery does not change the stomach anatomy permanently. This suggests that the issue is with the metabolizing of alcohol because of the changes in the bodies anatomy after the surgery.
A bariatric surgeon at Stanford School of Medicine, John Sanford, believes this is a physical issue not one of substituting addictions. He says the surgery causes a “heightened sensitivity to alcohol.”  The liver and stomach work together to metabolize alcohol using various enzymes. One of which is dehydrogenase and produced partly by the stomach. With less stomach, gastric-bypass patients produce less enzyme so that more alcohol enters the bloodstream. Or, as a New York Lenox Hill Hospital specialist Mitch Roslin says, it is like drinking on an empty stomach, therefore it is easier to get drunk and takes longer to sober up.
While it is not known for certain exactly what causes patients who receive gastric-bypass surgery to become sensitized to alcohol, leading to increased drinking and possible dependence, those who have the surgery should be aware of the risks involved. It is recommended that if possible gastric-bypass patients avoid alcohol completely during the period when weight loss is rapid, keep in mind that even a little alcohol can cause them to become intoxicated, eat before drinking, and do not drink and drive.


 
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