<<Disclaimer: Verify this information before applying it to your situation.>>

Fatigue is reported to be almost a universal symptom in newly diagnosed patients
with CD.  It may be due to one or more factors including malnutrition,
dehydration, inflammation (of the intestine), micronutrient deficiency causing
anemia, low calcium or magnesium, along with other deficiency states.
When a patient who has already has the diagnosis of celiac disease for several
years it can be any of the above, though the imporatant first step in checking
someone like that out is usually rechecking for activity of the CD.
Other entities that can cause fatigue that may be seen in higher frequency in
patients with celiac disease, include depression, vit b12 def, other autoimmune
diseases in cluding  sjogren's syndrome, lupus, hypothroidism, diabetes,
addison's among others,
Of course someone can also develope other illnesses including heart, lung,
liver, and kidney problems that can all cause fatigue, but are not associated
with CD
This is not medical advice and should not be used as such.
Joe Murray