Shark cartilage
Encyclopedia
Shark cartilage is a dietary supplement
made from the dried and powdered cartilage
of a shark
; that is, from the tough material that composes a shark's skeleton. Shark cartilage is claimed to combat and/or prevent a variety of illnesses, most notably cancer
. It is often marketed under the names Carticin, Cartilade, or BeneFin. A derivative of it named Neovastat was tested by AEterna Zentaris
as an angiogenesis inhibitor
and showed promising results in animals. Two clinical trials of Neovastat were completed in 2007, showing negative results.
The benefits of this supplement have not been scientifically proven, nor has shark cartilage been reviewed by the U.S. Food and Drug Administration
(FDA). However, its pervasive use is due to the mistaken notion that shark
s do not get cancer
and that shark cartilage contains angiogenesis inhibitor. This idea became popular with the best-selling book Sharks Don't Get Cancer by Dr. William Lane, published in 1992. This assertion even appears in the film on sharks at the Monterey Bay Aquarium
(although the aquarium does not endorse the use of shark cartilage), and in commercials for the National Geographic Channel.
from users as to its efficacy. The proponents also cite studies that show that shark cartilage has had some success in preventing angiogenesis
, the growth of new blood vessels from pre-existing vessels. While angiogenesis is often a normal function, it is also consistent with the growth of malignant tumors. They argue too, that very little research (in the quantity and quality of studies) has been conducted, and thus the benefits cannot be scientifically disputed.
Opponents cite existing studies of shark cartilage on a variety of cancers that produced negligible to non-existent results in the prevention or treatment of cancer. Most notable among these was a breast-cancer trial conducted by the Mayo Clinic
that stated that the trial "was unable to demonstrate any suggestion of efficacy for this shark cartilage product in patients with advanced cancer." The results of another clinical trial were presented at the 43rd annual meeting of the American Society for Clinical Oncology. In that study (sponsored by the National Cancer Institute), "researchers did not find a statistical difference in survival" between patients receiving shark cartilage and those taking a placebo.http://www.nytimes.com/2007/06/03/health/03cancer.html?ref=health Scientific evidence does not support the efficacy of shark cartilage nor the ability of effective components to remove cancer cells. The fact that people believe eating shark cartilage can cure cancer shows the serious potential impacts of pseudoscience
.http://cancerres.aacrjournals.org/content/64/23/8485.full
Detractors also purport that previous beliefs in regards to sharks and cancer have been overturned, as forty-two varieties of cancer have now been discovered in sharks and related species. Also, many opponents feel that non-existent (or even limited) results do not justify the rampant over-fishing of many endangered species of sharks, further threatening their extinction.
The protein involved in inhibiting angiogenesis would have to be injected into the bloodstream to have any effect on the cancer in the body. When a patient takes shark cartilage orally the protein is digested before it reaches the area of the tumor. Not all cancers rely on angiogenesis for energy.
Advocates
Opponents
Dietary supplement
A dietary supplement, also known as food supplement or nutritional supplement, is a preparation intended to supplement the diet and provide nutrients, such as vitamins, minerals, fiber, fatty acids, or amino acids, that may be missing or may not be consumed in sufficient quantities in a person's diet...
made from the dried and powdered cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...
of a shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
; that is, from the tough material that composes a shark's skeleton. Shark cartilage is claimed to combat and/or prevent a variety of illnesses, most notably cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
. It is often marketed under the names Carticin, Cartilade, or BeneFin. A derivative of it named Neovastat was tested by AEterna Zentaris
Aeterna Zentaris
Æterna Zentaris Inc. is a Quebec, Canada-based biopharmaceutical company focused in oncology and endocrine therapy. It has over 100 employees in Canada, USA and Germany. The company is based in Canada, the development and research site ist based in Germany...
as an angiogenesis inhibitor
Angiogenesis inhibitor
An angiogenesis inhibitor is a substance that inhibits the growth of new blood vessels . Some angiogenesis inhibitors are a normal part of the body's control, some are administered as drugs, and some come from diet....
and showed promising results in animals. Two clinical trials of Neovastat were completed in 2007, showing negative results.
The benefits of this supplement have not been scientifically proven, nor has shark cartilage been reviewed by the U.S. Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
(FDA). However, its pervasive use is due to the mistaken notion that shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
s do not get cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
and that shark cartilage contains angiogenesis inhibitor. This idea became popular with the best-selling book Sharks Don't Get Cancer by Dr. William Lane, published in 1992. This assertion even appears in the film on sharks at the Monterey Bay Aquarium
Monterey Bay Aquarium
The Monterey Bay Aquarium is located on the former site of a sardine cannery on Cannery Row of the Pacific Ocean shoreline in Monterey, California. It has an annual attendance of 1.8 million visitors. It holds thousands of plants and animals, representing 623 separate named species on display...
(although the aquarium does not endorse the use of shark cartilage), and in commercials for the National Geographic Channel.
Criticism and controversy
Proponents of shark cartilage are encouraged by anecdotal evidenceAnecdotal evidence
The expression anecdotal evidence refers to evidence from anecdotes. Because of the small sample, there is a larger chance that it may be true but unreliable due to cherry-picked or otherwise unrepresentative of typical cases....
from users as to its efficacy. The proponents also cite studies that show that shark cartilage has had some success in preventing angiogenesis
Angiogenesis
Angiogenesis is the physiological process involving the growth of new blood vessels from pre-existing vessels. Though there has been some debate over terminology, vasculogenesis is the term used for spontaneous blood-vessel formation, and intussusception is the term for the formation of new blood...
, the growth of new blood vessels from pre-existing vessels. While angiogenesis is often a normal function, it is also consistent with the growth of malignant tumors. They argue too, that very little research (in the quantity and quality of studies) has been conducted, and thus the benefits cannot be scientifically disputed.
Opponents cite existing studies of shark cartilage on a variety of cancers that produced negligible to non-existent results in the prevention or treatment of cancer. Most notable among these was a breast-cancer trial conducted by the Mayo Clinic
Mayo Clinic
Mayo Clinic is a not-for-profit medical practice and medical research group specializing in treating difficult patients . Patients are referred to Mayo Clinic from across the U.S. and the world, and it is known for innovative and effective treatments. Mayo Clinic is known for being at the top of...
that stated that the trial "was unable to demonstrate any suggestion of efficacy for this shark cartilage product in patients with advanced cancer." The results of another clinical trial were presented at the 43rd annual meeting of the American Society for Clinical Oncology. In that study (sponsored by the National Cancer Institute), "researchers did not find a statistical difference in survival" between patients receiving shark cartilage and those taking a placebo.http://www.nytimes.com/2007/06/03/health/03cancer.html?ref=health Scientific evidence does not support the efficacy of shark cartilage nor the ability of effective components to remove cancer cells. The fact that people believe eating shark cartilage can cure cancer shows the serious potential impacts of pseudoscience
Pseudoscience
Pseudoscience is a claim, belief, or practice which is presented as scientific, but which does not adhere to a valid scientific method, lacks supporting evidence or plausibility, cannot be reliably tested, or otherwise lacks scientific status...
.http://cancerres.aacrjournals.org/content/64/23/8485.full
Detractors also purport that previous beliefs in regards to sharks and cancer have been overturned, as forty-two varieties of cancer have now been discovered in sharks and related species. Also, many opponents feel that non-existent (or even limited) results do not justify the rampant over-fishing of many endangered species of sharks, further threatening their extinction.
The protein involved in inhibiting angiogenesis would have to be injected into the bloodstream to have any effect on the cancer in the body. When a patient takes shark cartilage orally the protein is digested before it reaches the area of the tumor. Not all cancers rely on angiogenesis for energy.
Legal action
In the summer of 2004, Lane Labs, the manufacturers of BeneFin, was ordered to cease the promotion of BeneFine as a treatment or cure for cancer, as they had not conducted any research as to their claims for the product, much less reported any potential side effects. Thus, the FDA ordered Lane Labs to "pay restitution to all of its customers from September of 1999 to the present."External links
General- Information on shark cartilage, from WebMD.com
- Do Sharks Hold Secret to Human Cancer Fight?, National Geographic
- Aetna InteliHealth, lists study results
Advocates
- REAL LIFE's Shark Cartilage Information Exchange, began in 1995
- Sharks Don't Get Cancer: How Shark Cartilage Could Save Your Life, William Lane, Ph.D., 1992. (ISBN 0-89529-520-2)
- The Angiogenesis Foundation
Opponents
- Shark Cartilage, American Cancer Society
- "Operation Cure.all" Nets Shark Cartilage Promoters, Federal Trade Commission
- Facts endangering sharks: Cartilage, The Shark Foundation