Celiac Patients and Gut Microbiota

By Alex Reis PhD, GFT science writer

 From the moment we’re born, every nook and cranny in our body is invaded by an army of invisible microbes intent on staying with us for the rest of our lives. Of all possible locations, the gastrointestinal tract is undoubtedly the most heavily populated organ, with an incredible 100 trillion bacteria from over 1,000 different species and collectively carrying 150 times as many genes as those in our genome. These “partners” we carry around with us can be either friend or foe, developing a fine balance which can be the difference between health and disease.

Since the Human Microbiome Project launched in 2008, the massive impact these tiny organisms can have in our health is slowly being unveiled. From the expected irritable bowel syndrome (IBS) to the rather surprising cardiovascular conditions and depression, the list of conditions that can be affected by an unbalanced microbiota keeps on growing. Celiac disease is one of those conditions.

How does celiac disease affect gut microbiota?
Like a finger print, each person has its own unique bacterial profile. There may be space for individuality, but most healthy individuals eating a balanced diet end up developing a rather friendly group of microbes, mostly dominated by gram-positive bacteria. These bacteria are very good at keeping invading pathogens at large and inhibiting food antigens, including from gluten.

This property would be extraordinarily useful for celiac patients. However, their gut microbiota may start on a “positive” note, but it’s gradually replaced by harmful gram-negative bacteria instead. As the balance starts to shift, these inflammation-causing bacteria take advantage of gram-positive’s weakened status and further aggravate the patient’s gluten intolerance.

The most important loss in gram-positive bacteria is seen in lactobacillus, bifidobacteria and some clostridium groups. Some of these, for example, are butyrate producers, an important energy source for intestinal cells, while others have essential anti-inflammatory properties.

As a result, the gut microbiota of celiac patients becomes dominated by the gram-negative Bacteroides-Prevotella group. Under normal circumstances, the gut is capable of keeping their inflammatory properties in check, but the system goes into overload as the numbers start to accumulate. Higher numbers of inflammatory-causing bacteria and a feeble immune response mean a constantly inflamed gut mucosa in celiac patients.

Can a gluten free diet solve the problem?
Currently, a gluten-free diet is the only available treatment for celiac patients. This diet alleviates many of the symptoms, but somewhat surprisingly, studies suggest it does not completely restore healthy microbiota profiles. It does restrict the presence of infection-causing bacteria, such as E. Coli, but there are some subtle changes caused by celiac disease that cannot be reverted.

It seems that it may be the diet itself preventing complete restoration of normal microbial patterns. Even in healthy patients subject to a gluten-free diet, the delicate balance between gram-positive and gram-negative is lost, with healthy bacteria quickly replaced by opportunistic pathogens. The long-term result may be weaker immune defences and chronic inflammation.

Interestingly, a diet that frequently leads to a lower intake of complex carbohydrates could explain these changes: normally these compounds reach the colon partially undigested and constitute an important energy source for friendly bacteria. Without this “food” supply, these bacteria lose their competitive advantage against any potential invaders.

This sets up a scenario where even a strict gluten free diet may leave celiac patients still susceptible to inflammation and infections, and potentially suffering rather unpleasant symptoms not to mention increased health risks. The answer may include better dietary counselling for celiac patients, including ways to promote a stable polysaccharide intake and appropriate diet supplementation.

This original article is made possible by Gluten Free Therapeutics. Our mission is to educate, inform, and provide the most effective nutritional products possible to allow those with celiac disease and serious gluten intolerances to heal their bodies. CeliVites complete line of superior gluten free supplements includes multivitamin/multimineral supplements, iron supplements, and calcium supplements for people living with celiac disease. All CeliVites products are designed to help you heal, restore and rebuild your body, because going gluten free isn’t enough! 

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