Shark Cartilage Receives IOM Draft Monograph 38662

Shark Cartilage Receives IOM Draft Monograph

WASHINGTON--A draft prototype monograph wasreleased Sept. 19 for shark cartilage, the second monograph released by theCommittee on the Framework for Evaluating the Safety of Dietary Supplements,which falls under the Institute of Medicine (IOM). The draft serves as acompendium of shark cartilage's possible adverse effects, as well as an overviewof other issues, including how cartilage supplements are prepared. This and theother four monographs still to be published are not intended to evaluate thebenefits of dietary supplements.

Based on the limited number of published clinical investigationsfor shark cartilage, evidence has not shown a direct association between use ofthis supplement and adverse event reports (AERs). Only one case report has beenpublished discussing a possible link between liver damage and the supplement,although the preparation and amount used were unknown. Four AERs have beenreported to the government's SN/AERS (Special Nutritional Adverse EventMonitoring System), including some where cartilage users cited side effects suchas lymphoma and jaundice, although causality was not able to be proven.Non-serious AERs included gastrointestinal distress such as nausea, diarrhea andflatulence.

However, the monograph reported that there was clear evidencedemonstrating shark cartilage has anti-angiogenic activity, which destroys orinterferes with the fine network of blood vessels needed by tumors to grow andspread. Even though this is good news on the cancer front, it is bad news forreproduction since angiogenesis is critical for the limb and skeletal formationof a fetus. Drugs with known anti-angiogenic activity have AERs such ashypertension, depression and leukopenia, an abnormal decrease in white bloodcells.

Safety concerns for shark cartilage products go beyond AERs. Oneconcern is that products made from any sea creature, including sharks, may becontaminated with heavy metals such as mercury. Also, shark cartilage can becomecontaminated in the same vein as uncooked animal products. Batches of sharkcartilage with a strong odor may be contaminated with squalamine, another anti-angiogenesiscompound found in the shark's liver and blood. Because of the strong smell, somemanufacturers use chlorine to cover the odor and bleach the cartilage. However,this practice could result in chemical contamination.

The draft in its entirety can be found at www.nas.edu.