Some Types of Gastric Bypass Surgery May Cause Digestive Tract Problems: Study

Individuals who undergo gastric bypass often experience side effects after the weight loss surgery, such as indigestion and food intolerances, according to the findings of new research. 

In a study published last month in the British Journal of Surgery, researchers found that more than 70% of patients who underwent gastric bypass surgery for weight loss also experienced food intolerances. Those patients also experienced more long-term gastrointestinal problems.

Researchers from the Netherlands followed-up with 249 patients who underwent laparoscopic Roux-en-Y gastric bypass surgery two years prior to the study, from May to October 2012. Laparoscopic Roux-en-Y gastric bypass is a weight loss surgery that reduces the stomach to the size of an egg. Patients lost an average of 31% of their total body weight.

The gastric bypass patients were compared to nearly 300 control patients who were morbidly obese and had not underwent surgery.

Participants completed a general health questionnaire, a Gastrointestinal Symptom Rating Scale (GSRS) questionnaire that focused on 16 gastrointestinal symptoms, and a food intolerance questionnaire.

Those who underwent gastric bypass surgery had a higher score on the GSRS questionnaire than patients who did not have surgery. The gastric bypass patients also experienced an average of two gastrointestinal symptoms, compared to the average of one symptom in patients who did not have surgery.

Researchers said the difference in symptoms of indigestion was most notable in surgery patients. Gastric bypass patients were more likely to experience indigestion, stomach gurgling, flatulence, belching, and hard or loose stools. Surgery patients also had more pronounced hunger pangs than the non-surgery group.

Researchers say this adds to a body of evidence that points to increased side effects and symptoms following weight loss surgery.

A study published in 2015 indicated patients who underwent bariatric surgeries faced an increased risk of fractures than patients who do not have weight loss surgery. Bariatric surgery patients face a 21% increased risk of breaking a bone within five years of their weight loss surgery.

In the new study, about 70% of patients who had gastric bypass also reported experiencing food intolerances, compared to 17% of the control group. Half of the gastric bypass patients experienced food intolerances to an average of four foods and 14% of patients said the intolerance was very bothersome.

The foods they most often reported intolerances to included fried foods, carbonated drinks, cakes, pies and pastries. These are foods doctors will often counsel gastric bypass patients to avoid following their surgery.

Some patients also had intolerances to ice cream and spicy food. Comparatively, the control group often experienced intolerances to milk and fried foods. Researchers said there was no relationship to the amount of weight loss and the number of food intolerances for the gastric bypass group.

Research published in 2014 also linked gastric bypass surgery to a higher risk of complications, compared to Lap-Band surgery. Gastric bypass surgery patients faced more complications, like death, re-hospitalization, and re-operation. Another study published in 2012 linked gastric bypass surgery to an increased risk of drug and alcohol addiction following surgery.