Shark cartilage is prepared from the skeleton of freshly caught sharks. A shark's skeleton is made of cartilage, not bone. The cartilage is cut from the shark, cleaned, and dried. It is finely ground, sterilized, and put into capsules.
Cartilage is taken from the spiny dogfish shark, hammerhead shark, and some other types of sharks.
They are not subject to the same scrutiny and regulations as prescription medicines. Many claims have been made that shark cartilage can cure cancer. Shark cartilage contains a substance that stops new blood vessels from forming and bringing blood to tumors. Without blood, tumors can't grow. For this reason some people think that shark cartilage will help stop tumors from growing in people.