Hello and thanks for the query
The black color stool is due to blood in it or presence of bile. Now we have to find out the cause of blood in the stool and that may be the cause for low hemoglobin
level. The causes may be infection of the digestive track which may be missed in endoscopy
. A biopsy
is needed to get to a diagnosis.
The other causes may be blood disorders, medications (like anti-coagulants) and chemical reaction or abuse. Try to chance your life style, take high fiber diet at proper time, take plenty of water, avoid junky, spicy and fatty food. Take light food in multiple doses.
In medication take regular antacids and PPI inhibitors. Consult your doctor for further advises.