Food sensitivities abound, the colonoscopy business is thriving, and your buddy just gave up beer because it gives him abdominal pain.

Seriously, what’s going on?!?

The increased incidence of allergies and food sensitivities is mainly confined to industrialized countries. According to the CDC, “food allergies are a growing food safety and public health concern that affect an estimated 4%-6% of children in the United States,” and have more than doubled over the past decade. Chances are, if you are an adult thirty-years or older, it was the rare child in your school who had a serious allergy. Now, children with allergies are becoming commonplace.

But it’s not just children. Sometimes it seems like just about every other adult I encounter has a form of abdominal pain that he or she regularly suffers from, and has been forced to give up some important staples: wheat, milk, eggs, and most tragic of all, coffee and beer.

So what’s causing our stomach problems?

Theories abound: vaccines, GMOs, introducing foods too early, the variety in the first-world diet, stress and anxiety.

On the physiological front, one theory that seems to be gaining traction is that our food issues are due to poor gut flora – the “good” bacteria that live inside of our digestive tract and aid in the digestion of food.

According to a 2010 article in CNN:

A study in Proceedings of the National Academy of Sciences compared the gut bacteria from 15 children in Florence, Italy, with gut bacteria in 14 children in a rural African village in Burkina Faso. They found that the variety of flora in these two groups was substantially different.

The children in the African village live in a community that produces its own food. The study authors say this is closer to how humans ate 10,000 years ago. Their diet is mostly vegetarian. By contrast, the local diet of European children contains more sugar, animal fat and calorie-dense foods. The study authors posit that these factors result in less biodiversity in the organisms found inside the gut of European children.

The decrease in richness of gut bacteria in Westerners may have something to do with the rise in allergies in industrialized countries, said Dr. Paolo Lionetti of the department of pediatrics at Meyer Children Hospital at the University of Florence. Sanitation measures and vaccines in the West may have controlled infectious disease, but they decreased exposure to a variety of bacteria may have opened the door to these other ailments.

“In a place where you can die [from] infectious diseases, but you don’t get allergy, obesity, asthma, inflammatory bowel disease, autoimmune disease, the flora is different,” Lionetti said.

This study only looked at a small number of children, but the findings support the widespread notion of the “hygiene hypothesis” — the idea that cases of allergies are increasing in number and severity because children grow up in environments that are simply too clean.

“That our immune system is skewed away from fighting infections, and toward fight things that it’s not supposed to be fighting, like things in the environment or foods — that’s one thing that people think may be in play,” Rudders said.

A recent study from the University of Chicago seemed to confirm this theory, as summarized in an article from Los Angeles’ PBS affiliate:

“Scientists took a group of mice with peanut allergies and gave them the gut bacteria Clostridia, a bacteria found commonly in humans. After administering it, they found that the mice no longer had food allergies…

Once introduced to the mice, the Clostridia acts as a barrier to keep the allergens in peanut proteins from entering their bloodstream. The allergens are still there, but they’re not able to produce the allergic reaction. Hence: No more food allergies.”

Among the things that can cause harm to gut bacteria are diet, an overly sanitized environment, and overuse of antibiotics, which napalm both the good and bad bacteria in your body.

Again, it’s just a theory, and is accompanied by theories about how to heal one’s gut flora. But whatever’s going on, it’s real, it’s negatively impacting people’s lives, and it needs some attention.