Charcoal is a fine, black powder made from wood or other natural materials by heating them in an airless environment. Charcoal used for health conditions is usually “activated” to make it a very fine powder, which increases its effectiveness. Activated charcoal can chemically attach, or adsorb, to a variety of particles and gases, which makes it ideal for removing potentially toxic substances from the digestive tract. Activated charcoal is not absorbed into the body, so it carries adsorbed substances out of the body in the feces.