Shark cartilage is part of the skeletal structure of sharks. Shark cartilage consists of about 40% protein, sea salt, and between 5% and 20% glycosaminoglycans.
In the early 1990s, the Harvard physician, Dr. William Lance, published a book, Sharks Donít Get Cancer, which spawned a flood of interest in this alternative treatment. Dr. Lanceís book was based on two assumptions: (a) Sharks do not get cancer, and (b) Shark cartilage contains a protein that helps prevent the formation of the new blood vessels (i.e.: a process called angiogenesis), which cancers need in order to grow. Since the publication of Dr. Lanceís book, however, it has been shown that sharks do indeed get cancer and that shark cartilage is not effective at treating malignancies in patients.
For example, in a clinical trial conducted in Denmark, 17 women with breast cancer were treated with shark cartilage. Only one of the women responded to the shark cartilage, whereas the breast cancer progressed (grew or spread) in the other patients in the study. Additional studies of the use of shark cartilage to treat cancer have produced similar results, indicating lack of benefit in treating cancer.
The bottom line is that shark cartilage does not work. In addition, shark cartilage has many potential side effects, and it is expensive. As with everything in life, we cannot believe everything we read. There are many people trying to make money marketing products and alleged treatments to cancer patients desperate for a cure. As with all alternative medicines, it is critical to research every therapy and herbal supplement thoroughly, and to make sure you are working with a qualified integrative medicine physician who can help guide you towards the most effective remedies.
Besides cancer patients, many other people were sucked into the shark cartilage scam, because they wanted to help prevent bone loss. The good news is that there are a number of different types of calcium supplements that people can take to help prevent bone loss.