By now, you've probably come across at least one product in a supermarket labeled "gluten-free."

These products have become more prevalent in recent years but you still may not know what "gluten-free" means. In fact, you're probably not sure what gluten is.

The prefix of the term "gluten" gives away its definition. Think of gluten as a glue-like substance that gives wheat and other products their chewy structure.

Although the science is much more complex than the definition, gluten can be defined, in lay terms, as the sticky protein substance in wheat.

Gluten is found in dozens of wheat-based products. It's also prevalent in rye as well as oats and barley (bad news for beer drinkers).

Related: 5 gluten-free beers

The chewy structure that is gluten might be pleasing to our palette, but it is detrimental to the one in 200 people who are estimated to have celiac disease, which according to the Center for Celiac Disease Research at the University of Maryland, is one of the most common life-long disorders in western countries.

People with celiac disease suffer from a laundry list of symptoms, including diarrhea, abdominal pain and bloating and other symptoms of Irritable Bowel Syndrome (IBS), which is now being recognized by some researchers as being caused by celiac disease.

In people with celiac disease, gliadin, a glycoprotein found in gluten, attacks the small intestine lining and causes damage to the tiny villi, which absorb nutrients. As a result of the body's inability to take in enough vitamins and minerals, autoimmune disorders can arise.

If you suffer frequently from headaches or migraines, or get sick a lot, or get skin rashes, you may have celiac disease or some other form of intolerance to gluten.

What's wrong with gluten?

Scientists say that for millennia humans subsisted on a diet consisting of nothing but wild game and meat as well as fruits and vegetables and nuts and seeds. It's only been since the Neolithic period (about 9500 BCE) that humans began cultivating wheat.

In evolutionary terms, that's the equivalent of a blink of an eye for when wheat was introduced into the modern diet.

To carry the metaphor further, it's been a fraction of a fraction of a blink of an eye that our food sources have been pumped with lots of wheat products and byproducts, all of which contain gluten.

Our guts are simply not adapted to digest gluten and break it down into individual amino acids.

About one in seven people have gluten sensitivity — that's 30 to 40 percent of the U.S. population. People with gluten intolerance are scientifically known as Non-Celiac Gluten Sensitive (NCGS).

Dr. Vikki Petersen, author of a new book, "The Gluten Effect," says that one of her missions is to dispel the myth that if you don't have celiac disease, you have nothing to worry about.

Don't reach for the Wheat Thins just yet, she cautions.

"Just because you don't have villous atrophy in the small intestine doesn't mean gluten isn't causing deleterious effect on your health," says Petersen, a chiropractor and clinical nutritionist.

With the increasing prevalence of gluten in our diets, Petersen says that there is now an increased risk of our genetics "flipping on" an anti-gliadin response.

This, predicts Petersen, will likely lead to more cases of celiac disease and autoimmune disorders caused by gluten intolerance.

"When you lump them together, autoimmune disorders are the third leading cause of death in the U.S.," says Petersen, "and gluten is a major culprit."

Petersen says that in the past, it was thought that you either have a genetic predisposition to gluten intolerance and celiac disease or you won't ever develop it. Research from just last year, she says, reveals this may not be the case.

She notes that since the 1970s, celiac disease has increased four fold and the disease was rare as recently as the 1950s.

Petersen says that due to the increased preponderance of toxins in our environment and food chain, gluten-free diets won't be considered merely a health fad.

"More and more people will suffer from the ill-effects of gluten-containing diets and will have to consume a 100 percent gluten-free food program," she says.

Is gluten-free enough?

"We should strive to eat as much organic and natural foods as we can to ensure proper health," Petersen says. "This includes increasing the amount of vegetables and gluten-free complex carbohydrates like quinoa, millet and brown rice."

Adopting a gluten-free diet, however, doesn't necessarily mean that those with celiac disease or gluten sensitivities will improve their health.

"One out of every three celiac disease sufferers fails to heal," says Petersen.

The culprit? Healing the gut takes more than switching from regular chocolate chip to gluten-free chocolate-chip cookies.

"There are secondary effects of gluten to consider, such as other food sensitivities, like dairy," says Petersen, who recommends those with celiac disease or NCGS get tested for secondary infections such as parasites, yeast overgrowth, amoebas and other nasty microscopic digestive invaders.

She also recommends taking a daily probiotic (human strain) with a micro-organism count of at least 20 billion — more if you have an infection.

Don't feast on gluten-free snacks. Instead, treat them as you would any other guilty-pleasure: a once-in-a-while treat. If you suffer from low energy and a myriad of health problems and tend to eat a lot of wheat and baked goods, consider going on a gluten-free diet.

It may be just what the doctor ordered.

Judd Handler is a graduate of the Functional Diagnostic Nutrition program, a curriculum that includes testing for mucosal barrier integrity of the small intestine. His website is WellnessGuru4u.com

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