Coffee is one of the most widely consumed beverages worldwide. Population studies suggest that coffee consumption protects against the progression of chronic liver disease and development of certain cancers and diabetes, but the mechanisms are not clear. Despite the ubiquity of coffee, the question as to whether coffee can cause ulcers or if it is safe after bariatric surgery is still ambiguous.

Coffee is a very popular beverage and consumed on a regular basis by millions. Most people who drink coffee daily will not deny that if they drink too much they will develop an upset stomach and indigestion. The question as to whether low doses or 'coffee in moderation' is healthy or unhealthy remains unanswered. The lack of scientific evidence in one direction or the other is actually surprising.

Coffee can induce dyspepsia and indigestion. Coffee directly and indirectly activates the cells of the stomach to secrete their hormones including signals to increase acid levels. Coffee stimulates gastrin release and gastric acid secretion. Therefore on one level, coffee should be avoided on the basis of its strong stimulatory effect on acid secretion. Decaffeinated coffee has an acid stimulating effect as well. Whether non-coffee caffeine-containing beverages induce ulcers is unknown, but they are still acid secretion stimulators.

The most conservative recommendation is to have any patient after bariatric surgery avoid coffee, decaffeinated coffee and all caffeine-containing beverages. However, the association between peptic disease, gastric irritation and symptoms remains unclear.

It has been suggested that drinking coffee on a regular basis can increase your chances of H pylori infection. H pylori is a bacteria that is known to be associated with ulcers and its eradication with triple therapy is typically enforced prior to gastric bypass.

Coffee has also been suggested to cause gastroesophageal reflux disease or GERD. Studies are not clear in this issue as well. Some experiments suggest that the ingredients in coffee may cause the muscular opening at the esophagus to open, thus increasing reflux, while other studies suggest no correlation.

The idea that coffee speeds digestion and increases the emptying of the stomach has also been examined. Compounds that were impregnated with radioactivity were used to assess the emptying times of the stomach. Different results have been reported by multiple labs. The consensus is that although coffee may change the contractility of various portions of the stomach and in some cases promotes gastric motility, it has an opposite effect on the small intestine and the net result is one that is not significant. Coffee increases the motor activity of the large intestine, or colon, within a few minutes after ingestion in some people. In affected subjects, its effects on the colon are found to be comparable to those of a very large meal. Coffee induces cholecystokinin release and gallbladder contraction, which may explain why patients with symptomatic gallstones often avoid drinking coffee.

Even though coffee is not considered to be responsible for development of peptic ulcer, it may, however, prolong its healing by increasing acidity of gastric content. A study has suggested that the detrimental effects of coffee on the irritation of the cells of the stomach reverse after 48 hours of abstinence from coffee.

Potential detrimental effects of caffeine consumption on exercise performance include gastric upset, withdrawal, sleep disturbance, and interactions with other dietary supplements. Caffeinated coffee should be assumed to share these same detriments.

Coffee does seem to have some beneficial aspects. Coffee drinking has been suggested to decrease the rates of stomach, liver, colon and some gynecological cancers.

Some people attribute indigestion to drinking coffee, suggesting that coffee affects one or more functions of the proximal gastrointestinal tract. Researchers have demonstrated that coffee, in comparison with water, enhances the relaxation of the top part of the stomach, but has no effect on its wall compliance, wall tension, or sensory function.

In conclusion, coffee has both benefit and detriment. The first few months after your operation represent a sensitive time both psychologically and physiologically. Depending on your operation, it is very important to allow any connections between the stomach and the intestine to heal. The first few months post-op are also complicated by problems with judging adequate hydration. Caffeine is a diuretic which means that it increases the amount that you urinate. If you are having trouble judging how much liquid to drink each hour means that coffee and caffeine will just complicate the situation.

Decaffeinated coffee can still cause some problems during the first few months after your operation as it also increases acid activity and may complicate the healing of any connections. If you are more than a few months after your operation then you most likely can resume moderate consumption of coffee. You must remember however to listen to your intestines and pay attention to any new pains or discomfort that may develop. If you start having diarrhea, epigastric pain or feelings of fullness and discomfort after drinking coffee then you either need to stop or decrease the amount that you are drinking considerably. If you develop an ulcer or a marginal ulcer than you definitely need to stop.