You should always see a doctor if you have black poop, especially if it's also sticky or tarry. Mild dehydration can lead to constipation and stool that's darker brown and harder than normal.

So although brown is the normal color, there are many variations ... For example, bismuth (the active ingredient in Pepto-Bismol) can color stool black. So can taking iron supplements and ...

Leading gastroenterologists reveal intriguing discoveries about black stool changes and what they mean for your health, from simple diet effects to warnings.

Although green, yellow, and brown hues are generally normal, black, red, or white poop may sometimes signal underlying issues. In the first week of life, a baby's stool changes from meconium to ...