Hello, Blood on smear test in stool is indicative of a source of bleeding somewhere in the gastrointestinal tract. Since the bleeding is mild it cannot be noticed either as blood in stool or as Malena that is black tarry stool. Anything that contains high iron in food or as supplement also can show the test to be positive hence you should stop any such thing for a while but it is also imperative to go for upper GI endoscopy to see whether there is gastritis or ulcer and colonoscopy to see for any disease that can cause bleeding in less quantity. These will be diagnostic and hence should be done and treated as per the findings. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. T Chandrakant