Similar to me. I lost ~20 lbs over 6 yrs without trying. Got scrawny. Had to beg Dr. for tests. Did fecal test and came back with Exocrine Pancreatic Insufficiency (EPI).

I am a fitness freak. Trying to gain is tough. Zenpep cleared up all the diarrhea etc, but gaining is proving hard. But at least not losing anymore.

See if gastro will order the test for you.