The most serious gluten-related condition is called celiac disease, which affects about one percent of the population. People with celiac disease who eat gluten-containing foods have severe digestive symptoms and often feel mentally clouded. Because the disease affects the digestive tract, it can interfere with the absorption of nutrients.
So, left untreated, you could end up with anemia and osteoporosis, for example. So it is important to take action. The good news is the nutritional treatment is 100% effective.
To diagnose celiac disease, doctors do blood tests to check for antibodies that are hallmarks of this condition. They also biopsy the small intestine to check for characteristic changes in the lining of the digestive tract. The treatment is to avoid gluten-containing products. It is important to maintain a gluten-free diet lifelong.
Some people have what is referred to as “gluten sensitivity.” They may have symptoms similar to celiac disease, but their blood tests show no antibodies and their intestinal biopsies show no signs of celiac disease. There is no specific test for gluten sensitivity, and the only way to know if you have it is to avoid gluten products to see if symptoms resolve. An estimated 7% of adults have gluten sensitivity.
Note that about 90% of people have no problem with gluten at all. There is no reason for them to avoid gluten-containing foods or to purchase gluten-free products.
A few people react only to wheat, and not to other grains. Their problem may be an allergy to a specific component of wheat, rather than to gluten, and they can freely eat the other grains.