Why Do Autistic People Have GI Problems?

Why Do Autistic People Have GI Problems?

Most people have experienced heartburn, stomachaches, constipation or diarrhea at some point in their life.  These gastrointestinal issues (GI) can be uncomfortable and inconvenient.  Autistic people are more likely to have GI issues compared to non-autistic people.  Research has shown that up to 91% of autistic people have GI issues.  The reason they have more issues can be broken down into 3 categories: issues in the gut, issues in the brain, and diet.

What GI issues do autistic people have?

Not all autistic people have the same GI issue.  There are 5 common problems and many others that are less common.  The 5 most common problems are:

• Constipation – Constipation means it is harder to or you are unable to have bowel movements (it’s harder to poop).
• Diarrhea – Diarrhea is a watery bowel movement.
• Abdominal Pain – Abdominal pain is also called a bellyache or stomachache. It can be caused by constipation, diarrhea, bloating, or another problem.
• Acid Reflux/GERD – Acid reflux is also called heartburn. It happens when the liquid in your stomach goes into your throat.  It is more common after eating and can make your chest or back hurt.
• Food Selectivity/“Picky Eating” – Many autistic people are sensitive to the taste and texture of food. They might only have a few meals they like, or they might need their food cooked a specific way.

What causes GI issues in autistic people?

There are many reasons why autistic people may have GI problems. Some of these causes are the same ones that affect people who are not autistic.  Other causes may be more closely linked to autism.  Every autistic person is different.  Two people can have the same GI symptoms but for very different reasons.  Because of this, it is not always easy to figure out what is causing someone’s stomach problems.  Doctors and researchers often group the possible causes of GI problems in autistic people into three main categories:

1. The gut – problems with the digestive system itself.
2. The brain – differences in how the brain and gut communicate.
3. Diet – the foods a person eats and how they affect digestion.

Understanding these three areas can help families and healthcare providers find the best way to treat GI problems.

The Gut:

There are thousands of different types of bacteria in a person’s gut.  This bacteria is good for us and helps us digest our food.  Research has shown that an autistic person has different amounts and types of bacteria in their gut. These changes can affect their ability to digest the food they eat which can cause GI issues.  Some autistic people also have “leaky guts” that make it difficult for their bodies to absorb nutrients from food, which can cause constipation and diarrhea.

The Brain:

The brain has a big role in controlling the gut.  It sends signals to the gut to start digesting food, and it helps control how fast food is digested.  Autism affects many parts of the brain including the part that sends signals to the gut.  Research shows that some autistic people’s brains don’t send signals that are strong enough to control digestion.  That can cause slow or abnormal digestion.

Diet:

Autistic people often have sensitivities to the taste, smell, and texture of different types of food.  They may eat only a few foods and often do not eat enough fruit or vegetables. This creates a diet that limits the amount, type, and nutrient value of food, and can cause GI issues and changes to the bacteria in the gut.

How can an autistic person improve their GI issues?

GI problems can be painful and uncomfortable, so they should not be ignored. It can be hard for some autistic people to explain where they hurt or describe their symptoms. Because of this, it is important to see a doctor if GI problems do not go away.  The doctor may do tests to find out what is causing the problem. Once they know the cause, they can recommend the right treatment.  Treatment may include medicine, changes to a person’s diet, or both.  In many cases, the treatment is the same as it would be for someone who is not autistic.

The doctor may also recommend meeting with a dietitian.  A dietitian can help make sure a person is eating enough fiber, vitamins, minerals, and other nutrients.  Eating a healthy, balanced diet can help improve many GI problems and support overall health.

Article by: Jacob Struble and The Autism Toolkit

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