Untreated celiac disease can lead to malnutrition due to malabsorption of vital nutrients in the small intestine, resulting in deficiencies that cause problems like anemia, stunted growth, and weight loss. Continued loss of fat and calcium can lead to conditions like rickets in children and osteoporosis characterized by fragile bones prone to fractures. In addition to gluten, dairy may also cause intolerance symptoms until the intestine heals, and non-treatment increases risk of cancers and neurological issues.