I spent a lot of money trying to find an iron supplement that did not bother my digestive tract but was not successful in doing so. Then I found a book about digestive problems and they suggested trying this instead of the actual iron and they were right it works without distress. The book The Gut Health Protocol states that the bad bacteria absorbs our nutrients with iron being one of their favorites. Iron in the form of ferritin stops this process according to the book so the bad bacteria will not be able to utilize the iron as a nutrient. All I know is that it seems to work for me so I recommend it for anemic people with sensitive digestive tracts or people with candida or bacterial overgrowth issues.