While it affects over 3 million Americans, it remains one of the more commonly misunderstood diseases.

It's name is Celiac disease, a digestive disease that damages the small intestine and interferes with absorption of nutrients from food.

People who have it are unable to tolerate the protein gluten, which is found in wheat, rye, barley, and possibly oats. When individuals with the disease eat foods that contain gluten, their immune system responds by damaging the small intestine.

The disease "is common", according to Dr. Ahmed Hasan, M.D. Board Certified in Gastroenterology and Internal Medicine. Hasan treats patients at both the Palmerton and Gnaden Huetten campuses of Blue Mountain Health Systems.

"It can manifest itself in many ways," Hasan said. "Once you recognize it, all you have to do is stay away from gluten."

Celiac disease is also associated with juvenile diabetes, thyroid disease, lupus, rheumatoid arthritis and small bowl cancer such as lymphoma, Hasan said.

As with any disease, early detection is important, said Hasan, who added Celiac disease can be diagnosed either through a blood test or a tissue biopsy. However, Hasan said the "gold standard" test is by taking a tissue sample or biopsy of the small bowl during an upper endoscopy.

"We want to make physicians aware," he said. "A lot of people are picking this up."

Hasan, who has the largest group of patients with Celiac disease in the area, said it's important that the disease be identified and checked.

"We're also in the process of a clinical trial with medication that may help symptoms of Celiac disease," he said. "The study I'm doing is the same as Thomas Jefferson University Hospitals in Philadelphia."

Celiac disease is the most common genetic disease in Europe. In Italy, about one in 250 people have it, and in Ireland, about one in every 300 people have it.

An estimated one in 140 Americans have been diagnosed with this disease. Approximately 3 million Americans across all ages and races suffer from Celiac disease, according to the National Foundation for Celiac Awareness. Also, 5.22 percent of Celiac patients have an immediate family member who has Celiac. Due to lack of awareness, a large number of patients with Celiac disease may be misdiagnosed as having irritable bowel syndrome.

In Italy, where Celiac disease is common, all children are screened by age 6. In addition, Italians of any age are tested for the disease as soon as they show symptoms.

As a result, the time between when symptoms begin and the disease is diagnosed is usually only two to three weeks.

In the United States, the time between the first symptoms and diagnosis averages about 10 years.

Along with Blue Mountain Health Systems, Hasan is also affiliated with Westfield Hospital and Westfield Surgical Center in Allentown.