By Mayo Clinic Staff. An X-ray is a quick, painless test that produces images of the structures inside your body â particularly your bones. X-ray beams pass through your body, and they are absorbed in different amounts depending on the density of the material they pass through.
Physical Causes. The most obvious reason for being tired and sleepy is lack of sleep. According to MayoClinic.com, the average adult needs between seven and eight hours of sleep every day. If you're sleeping less than that, adjusting your sleeping schedule might provide some relief.
Medical Conditions. Anemia -- an insufficient number of red blood cells -- can cause feelings of being tired all the time, and so can almost any major chronic illness, including cancer, heart disease and uncontrolled diabetes.