Sonal Kumar, MD, MPH, is a board-certified gastroenterologist and hepatologist at Weill Cornell Medicine/New York Presbyterian Hospital, where she is an Assistant Professor of Medicine and the Director of Clinical Hepatology.
While it may not be well known, type 1 diabetes and type 2 diabetes (conditions associated with too much sugar in the blood) can lead to problems with the stomach and the intestines. There are several reasons for this, including nerve damage caused by high or uncontrolled blood sugar.
Gastrointestinal (GI) symptoms can vary, ranging from acid reflux to diarrhea to constipation. Digestive problems can interfere with work and socializing, so getting a diagnosis and treatment are important to living a full and productive life.
This article will discuss the potential complications of diabetes that affect the digestive tract, the symptoms, and how they may be treated.
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Several types of digestive conditions are common in people with diabetes. They might be caused by the effect that higher blood sugar has on the systems in the body, which includes the GI system.
Gastroesophageal reflux disease (GERD) may be more common in people who live with diabetes. GERD is a condition that can cause symptoms such as:
GERD is caused by a problem with the valve at the bottom of the esophagus (food tube) called the lower esophageal sphincter (LES). If the LES isn’t closing and opening at the right times, stomach acid can back up into the throat, causing symptoms of GERD
People with diabetes may also be more likely to develop GERD if they also have gastroparesis or esophageal dysmotility. In gastroparesis, the stomach empties food out slower than it should. It also can increase pressure inside the stomach. The increased pressure puts stress on the LES.
Esophageal dysmotility can develop in people with diabetes. "Dysmotility" means that the muscles of the esophagus are not working well. This includes food moving too slowly or even muscle spasms. It can lead to symptoms such as heartburn and regurgitation.
People with diabetes are at a higher risk for developing gastroparesis than people who don’t have diabetes. This condition is more common in women than in men. Gastroparesis causes the stomach to empty of food slower than it should. The symptoms include abdominal discomfort and early satiety (feeling full).
Gastroparesis may be caused by nerve damage that is related to diabetes. Long periods of higher-than-normal blood sugar can damage the nerves, which is called autonomic neuropathy. This might also affect the nerves in various parts of the body, including the stomach.
Blood sugar that is higher than it should be for long periods of time can lead to autonomic neuropathy and related conditions such as gastroparesis.
Diabetes can cause nerve damage, called neuropathy. It typically develops in the extremities, which is why people with diabetes are encouraged to pay special attention to their feet. The nerve damage can cause a lack of sensation, and sores or injuries may go unnoticed because pain isn’t felt.
This nerve damage can extend to internal organs, including the intestines. Diabetic neuropathy is associated with having uncontrolled glucose levels and having diabetes for a longer time. Some of the symptoms in the digestive tract can include:
Constipation can be a complication of diabetes. It may occur as a result of enteropathy. The nerves in the colon may be damaged, leading to the muscles not working as well to move stool through and causing hard bowel movements. This complication can affect up to 60% of people with long-standing diabetes.
Medications used to treat diabetes or its complications, such as those that lower blood glucose levels, may also cause constipation.
Complications from constipation are rare. However, constipation can significantly reduce a person’s quality of life.
As many as 20% of people with diabetic enteropathy may have diarrhea, especially nighttime diarrhea, which can lead to lost sleep and even incontinence. Diabetic medications can also cause diarrhea.
Fecal incontinence is losing control of the bowel and having bathroom accidents. It can result from diabetic enteropathy, when the muscles of the anus lose their ability to function the way they should. This could lead to leaking or loss of control.
Hyperglycemia (high blood sugar) and rapid changes in glucose levels are also associated with incontinence. They can cause the rectal sphincter (the rings of muscle surrounding the anus that control the release of stool) to be less effective at holding in stool.
Fecal incontinence is sometimes not recognized or managed well. This can cause people to feel isolated, depressed, unable to work or socialize, and needing mental health support.
Abdominal pain is one of the common problems experienced by people with diabetes, with up to 60% of people reporting it. It can be associated with other GI conditions, such as gastroparesis and GERD. Around 74% of people with diabetic enteropathy report abdominal pain.
Small intestinal bacterial overgrowth (SIBO) is when there is an imbalance in the bacteria in the small intestine. It is associated with various conditions, including slower transit times (the time it takes for food to pass through the digestive system). Food moving too slowly through the small intestine can occur in people with diabetes.
Symptoms of SIBO include bloating, diarrhea, and abdominal discomfort.
With SIBO, a disruption in the microbiome (the balance of different types of bacteria in the gut) can occur. If the bacteria levels in the small intestine get out of balance, which can happen to people with diabetes, SIBO may result.
SIBO is fairly common. It affects about 15% to 40% of people with diabetes. For those who have diarrhea, SIBO may be more prevalent.
The treatment for digestive problems associated with diabetes will depend on the diagnosis. It's also important to look into any other digestive conditions that could be causing symptoms.
A major part of treating all diabetes complications is managing blood glucose levels to keep them within the recommended range.
To treat GERD, weight loss might be recommended, when appropriate. Treatment can include lifestyle changes, such as elevating your head during sleep, not overeating, avoiding trigger foods, and stopping smoking.
Medications such as proton pump inhibitors or histamine H2 antagonists might also be used, but these might interact with diabetes medications. For severe cases, surgery may be recommended.
Gastroparesis is often controlled with dietary changes, such as eating several small meals a day instead of fewer large ones. Treatment in more severe cases can include medications to stimulate the stomach muscles or to control symptoms of nausea and vomiting.
In people who do not respond to dietary modifications and medications, gastric electrical stimulation and pacing can be considered. A gastric pacemaker is placed surgically.
In gastroparesis, there’s a need to ensure that nutritional needs are met. People might need supportive care if they are experiencing dehydration, electrolyte imbalances, and nutrient deficiencies. This can include working with a dietitian to create an eating plan.
Diabetic enteropathy can cause a wide range of digestive symptoms. It might be important first to understand more about the symptoms and rule out other possible causes before treatment starts.
Having improved blood glucose control will be a major focus. To address symptoms, nutritional counseling and dietary changes such as eating small, frequent meals often are an initial step. After that, treating symptoms like diarrhea or conditions like SIBO might be the next step.
The first treatments for constipation may include dietary changes such as eating more fiber or taking fiber supplements, hydration, improving blood glucose control, and changing or stopping any medications that might be contributing to the problem.
Laxatives might be of help, but they should only be used under the direction of a healthcare provider. Few prescription medications are available for treating constipation, but Amitiza (lubiprostone) might be tried.
Diarrhea can be from various causes that may or may not be related to diabetes. Determining the cause by testing can help rule out diarrhea from other causes (such as a form of colitis or an irritable bowel syndrome) might be the first step.
After that, dietary changes (such as adding fiber), medication adjustments, and antidiarrheal medications (both over-the-counter or prescription) might be tried.
When fecal Incontinence is thought to be related to diarrhea, getting the loose stools firmed up may be helpful. This can include adding fiber to the diet or antidiarrheal drugs.
Biofeedback therapy or bowel retraining are other options that may be available and helpful for some people. Surgery might be considered for those needing more specialized care because of an injury or loss of function in the anal sphincter.
Abdominal pain can be from various causes, and treating underlying diabetes or other issues may help. For those experiencing more severe pain or if it doesn’t get better with treatment, prescription medications such as Lyrica (pregabalin) or Elavil (amitriptyline) might be recommended.
Biofeedback or referral to a pain specialist may also be considered.
For SIBO, the treatment is a course of antibiotics, which can include rifaximin, amoxicillin-clavulanic acid, metronidazole, neomycin, or lubiprostone. Changing the microbiome may be a treatment in the future, but it’s not known what types of gut bacteria are helpful, and there is little data available.
It may not always be possible to prevent the digestive complications of diabetes. However, maintaining good glucose control and getting regular care from a healthcare provider may help.
Another factor in prevention is to understand that digestive issues related to diabetes are possible and to recognize them early so they can be treated. Discussing digestive health with healthcare providers is important, as is bringing up any new symptoms immediately to get them addressed.
Type 1 and type 2 diabetes is associated with a wide range of gastrointestinal symptoms. In some cases, they may result from nerve damage to the digestive system. Receiving proper care for diabetes is important to managing symptoms and preventing complications.
Problems like constipation and diarrhea are common in people with diabetes but they are not often talked about, even with healthcare providers. There’s so much stigma surrounding digestive problems, especially with accidents.
However, there’s much that’s understood about how diabetes affects the digestive tract, and there are treatments that can help. It’s important to talk about stomach problems with a healthcare provider as soon as they start because a medical provider can help find the right treatment.
When the stomach works slower than it should to empty it of food, it can lead to symptoms such as:
Diabetes can cause blood glucose levels to be erratic: sometimes too high and sometimes too low. When there is excess sugar in the bloodstream from blood glucose levels being too high, it can cause damage to certain body systems. This includes the nervous system.
When nerves are affected, it can cause them to work less well and lead to symptoms in the stomach and the intestines, such as food moving too slowly, pain, constipation, or diarrhea.
People with diabetes may experience bloating or gas. This could be because of the damage that diabetes causes to the body, or because of a side effect of medications. It will be important to discuss these symptoms with a healthcare provider in order to find the cause and get treatment.
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Amber J. Tresca is a freelance writer and speaker who covers digestive conditions, including IBD. She was diagnosed with ulcerative colitis at age 16.
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