The Skin and Bones of the Matter

By Jemma Robinson

Sharks’ Plight

For a number of years now, I have held a love and deep fascination for sharks – both in awe of their majestic presence as well as appreciative of their unbridled power – yet the plight of the shark has come under question time and time again; portrayed as ‘man eaters’ the infamous shark is quickly disappearing from our oceans, showing a reduction of almost 80% of the world’s population in the last 50 years. Many shark populations are destined for collapse; many estimate that if the current overfishing in many parts of the world continues sharks, they fear, are likely to be in the first round of marine extinctions caused by man. Despite their fierce appearance, sharks are considered vulnerable owing to their longevity, late maturity and slow reproduction rates.  More than 800,000 tons of sharks were officially reported as caught in 1998, while a similar amount is thought to go unreported.

Shark Fin Soup

Throughout the ages, the Chinese have considered shark fin one of the eight treasured foods from the sea. The fact that so little is obtained from such a large fish made fins noble and precious, fit for the tables of the emperors. Fins were indeed listed as articles of tribute when officers of coastal regions visited the emperors in the Imperial court.  Fins are traditionally served at dinner parties to express the host’s respect for his guests. To this day the practice still holds true in Chinese communities. They are most frequently consumed on auspicious occasions, such as weddings.

The practice is particularly crude and cruel. The “finners” will pull the live sharks onto the boat, hack off some or all of their fins, then throw the shark, usually still alive, back into the water. Unable to swim, the sharks sink to the bottom of the sea and die a long and agonising death, either by being eaten alive by other fish or drowning due to the lack of oxygenated water flowing over their gills.  The carcass as a whole is difficult for the fishermen to store and would mean less space for fins, which are able to be dried and kept for months.

The fins are sold primarily to China for shark fin soup, a symbol of affluence and said to contain healing properties. According to a report by the group Wildaid, shark fins are now among the most expensive seafood products in the world, selling for $700 per kilogram on the Hong Kong market. Demand for shark fins has increased with China’s economic growth, but with the creation of a new middle class in China with disposable income, what was once rare is now common at weddings and corporate banquets.

Traditional Chinese Medicine (TCM)

The benefits of shark fin as documented by old Chinese medical books include the following: rejuvenation, appetite enhancement, and nourishment for the blood. Sharks fin is also thought to beneficial to the vital energy and many parts of the body including the  kidneys, lungs and bones.  On a radio show in China, when the owner of a shark fin restaurant was asked about the health benefits of shark fin, he claimed that he consumed it daily to maintain his youthful appearance. An elderly shark fin trader reasoned that, since fins have had long years of exercise in the sea, there is no doubt that they are good for the bones and muscles of the consumer.

However, there seems to be an increasing number of people who question the claimed benefits of fins. They are of the opinion that fins are overpriced and overrated. Their main purpose as luxury products is seen to be to satisfy the vanity of those who can afford them at the expense of the shark.  Most  feel that sharks fin soup is as tasteless in flavour as sharks finning is in practice. The efficacy of the claimed health benefits has been called into question numerous times.  It has been found that if consumed in extremely large quantities, shark fin soup may cause sterility in men due to mercury content – not a desired effect, I’m sure!

The fins that don’t find themselves in soup are ground up and used to make pills and tonics, said to have many medical properties: from curing headaches to preventing cancer. The argument for the latter being that since sharks don’t appear to suffer from cancer this must mean that consuming the shark will prevent cancer!  There is, of course, little medical or scientific evidence to back this up and many researchers and practitioners of TCM in China and the United States argue the need to study TCM’s efficacy with controlled, double blind experiments.

Cancer Drugs

Medical researchers became intrigued by the cancer prevention idea, and are now studying sharks. They believe that sharks’ ability to fight disease can teach us much about human sicknesses. Not only do they not often get cancer, sharks don’t often get any kinds of illnesses. They have very simple immune systems that fight disease much better than humans’ systems do. Medical researchers find this fact alone to be a good reason to study the way that shark immune systems work. But there is another, better reason inspiring the decision to study sharks as a means to finding a possible cure for cancer.

In the 1960s, research showed that cancers make a chemical called angiogenin that causes blood vessels to grow. Cancer cells need the increased blood flow that the growth of extra blood vessels provides, or the cancer cells will die. Scientists hypothesized that since cartilage has almost no blood vessels, it might produce an angiogenin that stops blood vessels from growing.

They set out to isolate this chemical: they found in animal studies that administering the angiogenin to rats with brain tumours showed a marked reduction in the size of the tumour (Robert Langer – Journal of Science). It was found that the angiogenin restricted the blood vessel growth and consequently starved the tumour of oxygen.  The drug in question has been derived from the backbone of the dogfish, a common smaller shark, and is currently being studied in hospitals in the USA and Canada.

It is always important to make the distinction between real science and TCM.  Whilst there are promising medical benefits to the use of shark derivatives, TCM like many of the alternative Chinese medicines are not regulated, and the dose is not monitored.  There are many unknown interactions with other chemicals, and until a mode of action has been identified, traditional Chinese medicines which use shark extract are unsafe.  Hopefully, a compound could be synthesised that will mimic the effects of angiogenin; however, I suspect that this will not curb the barbaric practice that is still ongoing in our oceans.

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