If celiac disease is properly managed, most people diagnosed with celiac disease can have a normal life expectancy. However, if celiac disease is not treated with a diet that is completely free of gluten, then the damage that is caused to the small intestine will continue and it could potentially be life threatening. When celiac disease goes untreated in adults or children, they become malnourished. Liver diseases and cancers of the digestive tract can also occur as a result of long-term unmanaged celiac disease. The most important thing if you suspect you or someone you care for has celiac disease is to get diagnosed so treatment can begin.