Sharks have been living on Earth for at least 400 million years, and are renowned for their longevity when not hunted or killed by accidental means. The sharks' reputations for long life are in part what is causing them to suffer overfishing and finning today, despite the fact that scientific research shows that shark cartilage "cancer cures" and other folk remedies do nothing to heal human ills.
Sharks and Disease
Sharks are generally a healthy lot, with anecdotal observations leading to the conclusion that the animals rarely become ill. Scientists who study sharks agree that sharks have an impressively low cancer rate, but have verified that sharks do get cancer. So do skates and rays, both of which can suffer some of the same diseases sharks get.
Scientists know that factors within living cartilage may help stop new blood vessels from growing - but this doesn't mean that taking shark cartilage supplements or other cartilage supplements can help people lower their own risk of cancer and other diseases. Besides the fact that millions of sharks are caught and killed for their fins each year, millions more are killed for their cartilage, under the misassumption that eating shark cartilage will help the body remain free of cancer.
Not only is this detrimental to sharks, it could even be detrimental to human health - not to mention a waste of money that could go to therapies which have been proven beneficial. The FDA has placed limits on claims about shark cartilage supplements in the USA, but wildly misleading health claims continue unchecked in many other places. Even so, shark cartilage supplements are top sellers - the demand is high, mainly due to a lack of education.
The fact is, the idea that ingesting shark cartilage can somehow make you healthier is just another myth about sharks. The first recorded shark tumor was described in 1908, and scientists today are finding higher numbers of sharks with cancer than ever before. The cancers are getting worse, too. A 2003 necropsy of an adult male blue shark which died after being caught accidentally yielded cancerous tumors in its liver as well as in its testes.
Like other vertebrates, including humans, sharks seem to contract cancer as a response to toxins and pollutants present in the environment. Other fishes are plagued by tumors, particularly those affecting the liver, when forced to live in polluted waters. In addition, sharks have a tendency to develop tumors when foreign bodies are present. For example, the blue shark mentioned earlier had a fishhook embedded in his side, which researchers theorize could have been a contributing factor to its liver cancer. No matter what caused the cancers in this shark and in others studied, one thing is for certain: sharks and their relatives are not immune to cancer.
There is no evidence that shark cartilage has curative powers of any type; and, despite clear cut cases of shark cancer, the slaughter of sharks for their cartilage continues. You can help debunk this dangerous myth by spreading the word, and sharing what you know about the important role sharks play in the environment.