Confusingly enough, a wheat allergy does not mean that an individual is allergic to gluten. If a person is allergic to wheat, they often experience common allergy symptoms such as hives, a runny nose, swollen lips or rashes. They also react negatively to any part of the wheat plant. They also should have no problem eating other sources of gluten, such as rye. (http://www.celiac.com/articles/23091/1/Celiac-Disease-vs-Gluten-Sensitivity-or-Gluten-Intolerance/Page1.html)
When people say wheat allergy, they often mean celiac disease. This disorder affects roughly one out of 133 people. In affected individuals, gluten triggers a negative immune system response which causes the body to attack its own intestinal lining. This often leads to gas, bloating, irritable bowels, diarrhea, weight loss, fatigue and difficulty concentrating. Failure to properly absorb nutrients can eventually also lead to conditions such as anemia, osteopenia, and osteoporosis (http://americanceliac.org/celiac-disease/).
Though the initial symptoms are unpleasant, the long-term consequences are far more worrying. Over time, the small intestine becomes progressively more inflamed and the body is subsequently starved of nutrients. This is especially problematic for growing children whose bodies need adequate nutrition. If the afflicted individual continues consuming gluten, their small intestine will continue to be unable to absorb the nutrients that they rest of the body needs. This lack of fundamental nutrition can permanently damage their brain, liver, nervous system and other vital organs.
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