Gastrointestinal Issues Associated with Obesity

Obesity is a complex, chronic disease that affects many systems in the body. While discussions around complications associated with obesity tend to focus on conditions such as heart disease and diabetes, obesity can also have a large influence on the development and severity of many digestive conditions.

Upper Gastrointestinal (GI)

Increased abdominal pressure resulting from excess abdominal body fat can cause or worsen several conditions in the upper gastrointestinal tract. The most common of these is gastroesophageal reflux disease (GERD),1 which occurs when the sphincter that closes off the lower portion of the muscular tube that connects the mouth to the stomach (esophagus) does not function properly. This causes stomach contents to flow back into the esophagus, which can cause many symptoms and complications.

Another condition that increased abdominal pressure can contribute to is hiatus hernia.2 The diaphragm is the muscle that we use to breathe. It sits horizontally in the body, separating the chest from the abdomen at the bottom of the rib cage. The esophagus goes through an opening (hiatus) in the diaphragm. Normally, this hiatus firmly grips the esophagus just above the stomach. However, in some individuals, the opening becomes wider than usual, allowing the esophagus to slip out of its normal position and part of the upper stomach to move upward through the large opening. This is a hiatus hernia.

The symptoms of GERD and hiatus hernia are often similar and include heartburn, acid reflux, chronic cough (from acid irritating the throat), bad breath, food regurgitation, and burning pain in the chest. You can manage either condition through dietary and lifestyle changes or medications, especially proton pump inhibitors (PPIs). Management of these conditions is important, as chronic reflux can in turn lead to more severe esophageal disease, such as Barrett’s esophagus and certain types of esophageal cancer.

Constipation

If you are eating a diet high in processed foods, meat, and/or dairy products and low in fibrous whole grains, legumes, and vegetables, then constipation is a concern. A person experiencing constipation has hard or lumpy stool, which is difficult to pass, and typically has fewer than three bowel movements per week. In addition, those who are trying to lose weight through dietary changes might be taking in less fibre, and food in general, and might also experience constipation. Increased abdominal pressure, either from obesity itself or from straining due to constipation, can also lead to hemorrhoids,3 which are enlarged or varicose veins of the anus and rectum.

The first line of treatment for both constipation and hemorrhoids involve eating a high fibre diet and drinking plenty of fluids along with regular exercise. If this is not enough to provide relief, then laxatives, of which there are many different types, can be helpful. Hemorrhoids will typically heal on their own, but there are also ointments for symptom relief and minor surgical options to treat them.

Diarrhea

Some foods, medication side effects, and bariatric surgery can lead to diarrhea. Overeating in general can trigger diarrhea in many people, especially when consuming dietary fats, fibrous fruits and vegetables, caffeinated beverages, and alcohol. Diarrhea can also become worse if you drink a lot of fluids with your meals. Weight loss medications, such as orlistat (Xenical®), and medications used to treat type 2 diabetes, such as metformin, can also increase diarrhea. Bariatric surgery sometimes prevents the proper absorption of food, which tends to result in diarrhea and the increased elimination of fat (steatorrhea) and other nutrients in stools.

Liver

Individuals who are living with obesity are also at an increased risk of developing non-alcoholic fatty liver disease (NAFLD),4 in which fat accumulates in the cells of the liver. While NAFLD is generally asymptomatic, it can eventually lead to the development of non-alcoholic steatohepatitis (NASH), in which there is severe inflammation in the liver. NASH can lead to irreversible late-stage scarring of liver tissue (cirrhosis). Luckily, there is evidence that early intervention using weight loss through diet, exercise, and medication can help to reverse inflammation and fat in the liver.

Gallbladder

There is also a link between gallstones and obesity, particularly in women.5 The gallbladder is a small organ located below the liver that stores and concentrates bile, an important digestive fluid made by the liver. When you eat, the gallbladder releases bile into the small intestine to help digest dietary fats. If bile contains too much cholesterol, gallstones can form. Many individuals have gallstones without any symptoms. However, they can cause severe pain, and in some cases block the bile duct. In these situations, surgery to remove the gallbladder is often necessary, but there are also medications that can help dissolve the stones. Gallstones are also much more common in those who lose weight rapidly.

Pancreatitis

Obesity might also play a role in the development of acute pancreatitis.6 Some conditions that you have a higher risk of developing if you have obesity, such as gallstones, diabetes, and high blood levels of triglycerides, as well as obesity treatments, such as bariatric surgery, can increase your chance of developing acute pancreatitis. In addition, excess body fat, particularly visceral fat, which is fat that surrounds your organs, can worsen the disease outcome. This means that you might experience symptoms earlier or symptoms that are more severe than someone with an ideal amount of body fat.

Conclusion

The effects of obesity can extend to many areas of the body, and the digestive tract is no exception. Many conditions can be caused or worsened by the physical and hormonal effects of excess body fat.


First published in the Inside Tract® newsletter issue 215 – 2020
Photo: © Krakenimages.com | bigstockphoto.com
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2. Khan M et al. Hiatal hernia and morbid obesity-‘Roux-en-Y gastric bypass’ the one step solution. J Surg Case Rep. 2019;2019(6):rjz189.
3. Riss S et al. The prevalence of hemorrhoids in adults. Int J Colorectal Dis. 2012 Feb;27(2):215-20.
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