It may be normal that the stool does not turn black after taking iron supplements, or it may be caused by gastrointestinal dysfunction and other diseases, which are not normal in such cases. Iron into the digestive tract needs to be digested, absorbed, only part of the unabsorbed iron will be discharged with the stool, resulting in black stool color, if the body can be fully absorbed iron may also appear in the stool did not turn black, this kind of situation is a normal phenomenon. However, for those who suffer from gastrointestinal diseases, such as gastrointestinal dysfunction, intestinal flora imbalance and other diseases when the intestinal function is abnormal, the iron agent does not have the ability to be completely oxidized by hydrogen sulfide in the intestinal tract into iron sulfide, which results in the stool did not turn black. If the stool does not turn black after taking iron supplements, you can go to the hospital and ask the doctor to make a judgment after eliminating physiological factors.