Shark Cartilage

Last Modified: January 28, 2011


Dear OncoLink "Ask The Experts,"

Can you tell me if shark cartilage has any effects on tumors? I have read some articles stating that it does, but they weren't written by an oncologist.


James M. Metz, MD, Editor-in-Chief of OncoLink and Assistant Professor of Radiation Oncology at the Hospital of the University of Pennsylvania, responds:

Thanks for your question on shark cartilage. Shark cartilage has an interesting story in how it became popular. It comes from the idea that sharks don't get cancer. However, this is false. Sharks develop a variety of cancers including tumors of the central nervous system. There was also a report on "60 Minutes" many years ago about a small group of patients in Cuba that received shark catilage with the scientific endpoint of "patients feeling better" after a few weeks of treatment. Outside review by the National Cancer Institute and others felt the study was really incomplete and not documented well. This was not reported in the program and shark cartilage became a sensation.

It has been shown to have some effect on blood vessel formation in the test tube. However, no scientific studies have shown it to be effective. There have also been a number of reports on supplies of shark cartilage being contaminated with other substances. At this point in time, there is no evidence to support the use of shark cartilage in cancer patients.

This question and answer was part of the OncoLink Brown Bag Chat Series. See the entire transcript of Integrating Complementary Therapies into Your Cancer Care.

From the National Cancer Institute