Health and Ethical Reasons to Avoid Shark-Based Foods and Supplements
At one time, shark cartilage supplements were popular as an effort to protect against cancer. Not only are these not effective, they may also harm your health.
There was once a widely circulated myth that sharks do not get cancer and it was thought that by ingesting some of their tissue, you could also protect yourself against the disease. The idea that sharks don’t get cancer can be traced back to scant clinical evidence that cartilage has antiangiogenic properties – meaning that it inhibits the development of blood vessels which are crucial to the growth of cancerous tumors.
By the way – sharks and other related fishes do get cancer, it is just more rare. And also, orally ingesting cartilage supplements have never proven to be of any help in either preventing or curing cancer in humans either because none of the beneficial components have the ability to be absorbed across intestinal walls. Unfortunately, some toxins in the supplements may reach our bloodstream and harm our health in other ways.
Shark Fins and Meat are Linked to Neurological Diseases
A new study by scientists at the University of Miami has found high concentrations of two dangerous toxins in the fins and muscles of 10 species of shark – mercury and B-N-methylamino-L-alanine, or BMAA – at levels that may pose a threat to human health.
"Recent studies have linked BMAA to neurodegenerative diseases such as Alzheimer's disease and amyotrophic lateral sclerosis (ALS)," said Deborah Mash, Professor of Neurology and senior author of the study.
Each by themselves are dangerous, but together, they may have synergistic toxic impacts. "Since sharks are predators, living higher up in the food web, their tissues tend to accumulate and concentrate toxins, which may not only pose a threat to shark health, but also put human consumers of shark parts at a health risk," said the study's lead author Neil Hammerschlag, a research assistant professor.
Here in the US, consumers do not tend to eat a lot of shark for food, but it is popular as a delicacy and a source of Traditional Chinese Medicine in Asian communities. A bowl of shark fin soup can sell for $100 at some restaurants and up to 75 million sharks per year are killed to provide this dish to consumers. Another 25 million or so are killed due to fishing practices. And our shark species are threatened - About 16% of the world’s shark species are now considered endangered.
While sharks may seem scary when they come to close to our beaches, they actually play an important role of protecting the earth by helping to maintain our oceans.
"People should be aware and consider restricting consumption of shark parts. Limiting the consumption of shark parts will have positive health benefits for consumers and positive conservation outcomes for sharks, many of which are threatened with extinction due in part to the growing high demand for shark fin soup and, to a lesser extent, for shark meat and cartilage products." said Hammerschlag.
Neil Hammerschlag, Deborah Mash, et al. Cyanobacterial Neurotoxin BMAA and Mercury in Sharks. Toxins, 2016; 8 (8): 238 DOI: 10.3390/toxins8080238
American Museum of Natural History
Scientific American: Mythbusting 101
Oceana.com – Why Healthy Oceans Need Sharks
By chee.hong – via Wikimedia Commons