Gluten is a protein molecule made of smaller units called amino acids. This elastic protein is found in some grains to give dough its structure and cohesiveness. In most people, the gluten molecule is broken down by digestive enzymes and is absorbed across the intestinal cells to provide energy for the body.
This normal process becomes harmful to a person with a hypersensitive or ill functioning immune system. In those with gluten intolerance, the gluten protein remains whole and indigestible. The immune system and gluten create an inflammatory reaction in the intestine, resulting in flattened or blunted intestinal cells. These damaged cells can no longer properly absorb the products of digestion resulting in the symptoms of diarrhea, fatty stools, cramping, bloating, and malnutrition.