The xylose absorption test is a medical procedure used to evaluate how well the intestines absorb a simple sugar called xylose. During the test, a patient drinks a solution containing xylose, and then urine and blood samples are collected to measure the amount of xylose absorbed. Low levels of xylose in these samples may indicate malabsorption issues, which can be caused by conditions like celiac disease or Crohn's disease. This test is particularly useful because it does not require the patient to follow a special diet beforehand. It helps doctors assess intestinal health and determine the underlying causes of gastrointestinal symptoms.