What’s Really Causing Your Irritable Bowel Syndrome?

Exploring different causes, same symptoms
fresh eggs and flour

By: Mark Hyman, MD

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You probably know if you have irritable bowel syndrome (IBS) — with symptoms like bloating or gas, distention, constipation, diarrhea, cramping, and most likely, running to the bathroom after you eat. In identifying the causes of these issues, here’s what you need to know. If there are five people with irritable bowel, each one of them may have different causes for the exact same symptoms.

As a functional medicine practitioner, I look for the root cause of disease, and this perspective lends itself to treatments that may differ from those of conventional medicine. Here, find an exploration of the root causes of IBS.

What causes disease?

When you narrow things down, the main causes of disease include:

  • Allergens.
  • Microbes or imbalance of the bugs in your gut.
  • Toxins.
  • Poor diet.
  • Stress.

All of these can trigger symptoms and create thousands of diseases. When it comes to IBS, there are many underlying culprits, however, research tells us the two main causes are food allergies and overgrowth of bacteria in the small intestine. Let’s briefly look at each.

Food sensitivities and allergies

A landmark paper published in the prestigious British medical journal Gut found eliminating foods identified through delayed food allergy testing (IgG antibodies) resulted in dramatic improvements in IBS symptoms.

Another article, an editorial in The American Journal of Gastroenterology, stated clearly that we must respect and recognize the role of food allergies and inflammation in IBS.

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Simply put, certain foods can irritate your bowel and digestive system. We call these food sensitivities, and they are very common. They aren’t true allergies like a peanut allergy or shellfish allergy, but rather a more mild food sensitivity that can cause terrible symptoms.

Some people may be sensitive to gluten, a protein found in wheat, barley, rye, oats, and spelt. Dairy can be another problem. The lactose it contains may cause bloating, gas, and diarrhea in some people. Dairy also contains proteins, like casein and whey, that also can cause irritation and inflammation in your gut.

Many other food sensitivities exist, including soy, corn and eggs. If you suspect food sensitivities contribute to your IBS or create other problems, I encourage you to eliminate dairy, gluten, and other potentially problematic foods for six weeks and see if your symptoms don’t improve.

Gut ecosystem imbalances

The surface area of your small intestine, where food is absorbed, is about the size of a tennis court. Your small intestine is also the site of about 60 percent of your immune system.

This sophisticated gut-immune system is one-cell layer away from all of the bacteria and undigested food particles in your gut. If that lining breaks down, your immune system will be exposed to foreign particles from food and bacteria and other microbes.

Many things can make your gut lining erode, including:

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  • Stress.
  • Too many antibiotics or anti-inflammatory drugs.
  • Steroids.
  • Intestinal infections.
  • A low-fiber, high-sugar diet.
  • Alcohol.

It’s possible for this erosion to trigger and activate an immune response, which may lead to irritable bowel symptoms.

The bacteria in your gut has to in balance for you to be healthy. We call this the human microbiome. For some people, it can be problematic to eat food that’s starchy like bread, cereal, pasta, rice, or sugary foods. It may cause bloating right after meals, which can be a symptom of bacterial overgrowth. We call that small intestinal bacterial overgrowth.

When your gut microbial ecosystem is healthy, you are healthy.  When you have too many pathogenic bacteria and not enough healthy bacteria, you become sick, inflamed, and more susceptible to problems like IBS.

This is precisely why it is so critically important to personalize treatment based on the unique circumstances that exist for each person who suffers from IBS. The solution is most certainly not one-size-fits-all. But solutions can be found if we look carefully at the underlying causes and treat them.

This story was adapted from Dr. Mark Hyman’s blog: This Gut Condition Affects One in Six People — And Is Entirely Curable.

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