30 April 2013

May Science Café: Sharks, cancer & pseudoscience

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TALLAHASSEE, Fla. — It’s an urban myth that got started nearly 40 years ago: Sharks don’t get cancer. But they do, as scientist Gary K. Ostrander knows only too well.

Gary K. Ostrander, FSU Vice President for Research.Gary K. Ostrander, FSU Vice President for Research.“We have documented 40 cases, plus or minus, of cancer in sharks,” Ostrander said of studies he did prior to becoming Florida State University’s vice president of research in 2012.

The myth surrounding shark cartilage and cancer really took off after the book, “Sharks Don’t Get Cancer” by I. William Lane and Linda Comac, came out in 1992 and prompted a “60 Minutes” television report. It launched a billion-dollar industry in shark cartilage and, said Ostrander, “none of it is true.”

Ostrander will talk more about sharks, cancer and bogus science at the May 7 Science Café, sponsored by the National High Magnetic Field Laboratory. Head to Ray’s Steel City Saloon, 515 John Knox Road, to hear his presentation, which begins at 6:15 p.m. and will last about an hour. Arrive early for a good seat and something tasty to nosh on.

“It’s a chance to talk about science and pseudoscience, critical thinking and the power of the press,” he said.

The idea that ingesting powdered shark cartilage to halt or prevent cancer in humans seems to have sprouted from a false hypothesis (sharks don’t get cancer) propped up by a few facts.

Ostrander, who earned his doctorate in Ocean and Fisheries Science in 1986 from the University of Washington, summarized the thinking: “Tissues and tumors need blood vessels to develop, and since cartilage doesn’t have blood vessels in it, a clever marketer basically said, 'Since sharks don’t get cancer, there must be something that prevents them from getting cancer — oh, I know, it must be the cartilage.'”

The money being made from this claim is substantial. Do a Google search, and you’ll find numerous shark-cartilage supplements for sale. In 2011, Americans spent about $3 million on such supplements, according to a May 8, 2012 New York Times article. The global value of shark fins ranges from $540 million to $1.2 billion annually, according to Wikipedia. (Sharks fins are also in demand for shark-fin soup, a dish considered an Asian delicacy.) Sales continue despite a finding last year by University of Miami scientists that showed samples of cartilage from seven shark species contained neurotoxins that have been linked with Alzheimer’s and Lou Gehrig’s disease.

While marketers are cashing in on the myth, the mighty predators are suffering from it.

“They catch the sharks, bring them on board while they’re still alive, cut off their fins and throw them overboard to die a pretty agonizing death,” Ostrander said. “They’re even harvesting the cartilage from whale sharks,” which are large, stunning sea creatures known for their gentle nature.

“I’m trying to educate people,” Ostrander said. “A big part of the message is spotting pseudoscience. People actually believe this stuff. I’m going to show experiments and clinical trials and the data that was put out and how they made the data look like it was in scientific papers, but it wasn’€™t really in scientific papers.”

Come hear more about sharks, their role in our planet’s ecosystem and how to identify phony science at the May 7 café. Science Café will take a summer break after Ostrander’s talk, then resume again in September with a new line-up of speakers.


The National High Magnetic Field Laboratory is the world’s largest and highest-powered magnet facility. Located at Florida State University, the University of Florida and Los Alamos National Laboratory, the interdisciplinary National MagLab hosts scientists from around the world to perform basic research in high magnetic fields, advancing our understanding of materials, energy and life. The lab is funded by the National Science Foundation (DMR-1157490) and the state of Florida. For more information, visit us online at nationalmaglab.org or follow us on Facebook, Twitter, Instagram and Pinterest at NationalMagLab.

Last modified on 10 November 2014