Gluten-free might feel like a fad, but for 3,000,000 people in the United States, it’s no laughing matter. Instead, life is a constant worry to ensure their next meal doesn’t leave them out of commission for hours, if not days. On the lighter end, symptoms of this condition can range from mild bloating, cramping, and gastrointestinal discomfort to constant bouts of diarrhea, peripheral neuropathy, and reduced bone mass. It can also cause malabsorption for essential nutrients and stunt growth in children. With over 200 potential symptoms related to Celiac disease, the growing concern and extended impact of this condition has health professionals around the world searching for the root cause.
Although the trigger of the condition may seem simple enough (as Celiac disease has only one known allergen: gluten), the disease itself speaks to a much larger concern: why did this allergen form - and where did it come from? Has this allergen been a part of humanity for eons, or is it manmade?
The truth is that the answer is quite complex, but maybe we can shed some light on it and understand where the research is going.
The Who, What, and When
Before the time of the agricultural revolution, humans were naturally hunters and gatherers, thriving off what they could catch and pick. Similar to most of life, this standard food sourcing practice was so historic, that the microbes that lived within the digestive systems of early humans evolved very efficiently to support this method. However, around 8,000 years ago, something changed. Humans began practicing civilized agriculture methods that fundamentally changed how we developed food, and the types of foods we consumed.
For some, the benefits outweighed the compromises: with agriculture, cultures became more food secure allowing civilizations to grow and blossom. With food abundance and ease came great technological advancements and the addition of time spent on other activities. The age of agriculture is what some historians and sociologists consider the first real opportunity for humans to become the highly-advanced individuals we are today. But with every action comes and equal and opposite reaction.
With the increase in foods (and types of foods) came the increase in exposure to food allergens. Most were able to adapt to them, while some could not.
The term “celiac” originated from a Greek physician named Aretaeus of Cappadocia during the first century (AD). His description of the “The Coeliac Affection” described individuals with bloated and distended digestive tracts who consistently suffered from gastrointestinal issues. It would be nearly 1800 years later that early scientists in the 19th century would begin exploring the cause of the disease, initially tying the link to starch found in grains, bread, and cereals. The disease cost many their lives, often causing patients to starve to death. Most frequently diagnosed in children, countless early studies were conducted in the 1920s until the great “banana” diet caught fame. This marked the first clinical diet to reduce symptoms associated with Celiac’s disease by completely cutting out any forms of carbohydrates outside of bananas.
It took another 30 years for scientists to isolate a specific protein as the allergen inducing the disease. But In 1953, Willem Dicke, Dolf Wijers and Jan Van de Kamer identified gluten to be the cause of the symptoms associated with Celiac.
The Root to the Root Cause
But if someone were to ask you off the street, “What causes Celiac disease?” - would answering “Gluten,” really be the answer?
Gluten does indeed cause an allergic reaction within the gut when it is consumed, inducing an immune response. But, how did it get there? Where did this allergy come from? Is it genetic, or is there something else going on?
It is questions like these that led scientists to immerse themselves in epidemiological studies that examined what actually happens in the gut when gluten is introduced. Epidemiology studies are used to compare notes between cases, prevalence, symptoms, as well as patient histories. These studies help source out what ties many patients of disease together, allowing researchers an opportunity to connect the dots and learn more about commonalities as well as differences.
What did epidemiology studies find? There seemed to be something in common with many patients with Celiac’s disease - and it had a lot to do with their gut microbiome.
Gut Dysbiosis: The Source-Code of Celiac’s Disease
There is no such thing as a “perfect” gut. Moreover, whatever changes are made to the diversity and balance of one person might not have the same effect on another. For many studies comparing the impact of the gut microbiome to disease - strategies to determine the bacteria responsible have been largely confounding. It appears that many bacteria that thrive in our gut ecosystem can wear many hats, and depending on the day (or even hour) their role and impact on disease could change. However, the link between gut dysbiosis, or imbalance in the gut ecosystem, and intestinal health is clearly evidenced. Without a well-balanced system, a person is inherently more likely to develop additional conditions that can find their origins right inside the digestive tract.
For Celiac disease, scientists have found substantial evidence showing how imbalance of gut microbe composition can increase the susceptibility one might have to food allergens, such as gluten. This has been attributed to the impact of the immune system in response to gut dysbiosis, though recent studies have noted that in celiac patients, heightened immune responses may be related to microbes promoting a pro-inflammatory environment. This may be due to issues of an individual’s “pattern-recognition receptors” or PRRs that are used to locate and recognize cells that are either foreign or familiar. PRRs help us determine if a pathogenic bacteria or other molecules belong inside us. They’re best known for catching allergens and causing the typical immune reaction. Deficiencies in the genes that code for PRRs have been shown to impact gut dysbiosis, making it even more evident how complex the origins of celiac disease are.
The truth? The research has yet to fully identify what is causing this disruption or at what window does gut microbial imbalance impact gluten-allergy formation. Yet - the evidence suggests that therapeutic targets of the gut microbiome might pave the way for many with Celiac disease by reintroducing microbes that can break down gluten or even focusing on ways to improve a person’s gut dysbiosis. The potential is there, which means we’re that much closer to finding a cure. That might just mean individuals diagnosed with Celiac can have their gluten-filled cake, and finally eat it too.