Most of us have heard claims made by companies that manufacture supplements made from sharks: “Sharks don’t get cancer!” they proclaim. “Take these supplements, and live cancer-free!” Nothing could be further from the truth – in fact, scientists have known that sharks really can get cancer for more than a century and a half. Yet for some reason, the belief that these essential apex predators can’t suffer from the disease persists – and that same belief keeps the market for shark-based supplements strong. Now, new photographic evidence – along with additional research – is helping to drive business away from those selling shark cartilage supplements.
Humans deadlier to Sharks than they are to Us
The results of a survey conducted in March of 2013 concluded that humans kill approximately one hundred million sharks each year. Though not all of those sharks are harvested for use by supplement manufacturers, demand for shark cartilage has been a major factor in the sharp decline in shark populations – even though there are no studies that show that shark cartilage is an effective anti-cancer agent or cancer treatment.
In an effort to prove once and for all that sharks do get cancer and taking supplements made from their bodies is useless, researchers have compiled a massive amount of evidence and are sharing it with consumers. In all, twenty-three shark species have now been proven to suffer from cancer just as other creatures do. A great white shark in Australia was photographed with a massive tumor protruding from its mouth, and a bronze whaler shark in nearby waters was also photographed with massive tumors including a foot-long mass emerging from the area above one of its eyes.
Shark biologist and study co-author Rachel Robbins says, “The main take home message from the study is that it adds to the growing evidence of tumor formation in sharks, contrary to popular belief that sharks do not suffer from such anomalies.”
David Shiffman, a University of Miami shark researcher, agrees wholeheartedly that it’s foolish to consume shark cartilage in hopes of reducing cancer risk. “Sharks get cancer,” he said. “Even if they didn’t get cancer, eating shark products won’t cure cancer any more than me eating Michael Jordan would make me better at basketball.”
Not only does the demand for shark cartilage fuel overfishing of sharks, rays, and skates, the belief that the substance can cure cancer has a deleterious effect on cancer patients, sometimes even diverting them from medical treatments that have been proven effective.
The reality is that just like humans and other animals, sharks are getting cancer at higher rates than ever, as are marine mammals. Though it’s unknown what caused the tumors recently seen in Australia, it is clear that the increased overall cancer rate in marine animals and land-dwelling species is probably linked to industrial pollutants and human activities. Sadly, these animals aren’t just in danger because of problems with the environment around them – according to the International Union for Conservation of Nature, one in six known shark, ray, and skate species is threatened – and that threat is directly linked to human consumption including cartilage supplements.