The term “cartilage” refers to an elastic, fibrous, and translucent tissue located on the ends of bones. It permits the smooth movements associated with joint activity. During the normal growth and development of humans, most cartilage converts into boney formations. The minority of cartilage, which is not used for bone formation, is deposited in the ears, nose, and joint cavities. It is a dense connective tissue that is valued for its shock absorption properties.
Cartilage acts as a buffer. A wide range of chronic, painful disorders often characterizes the lack or degradation of this tissue. There are three different types of cartilage, and each is classified by its strength, elasticity, and structure. Commercial cartilage supplements purchased from nutritional retailers are actually products containing cartilage harvested from either certain shark species or bovine tracheal tissue.
But why have cartilage supplements acquired so much public interest in the last decade? One answer may be media coverage. In all likelihood, shark cartilage was the dietary supplement to receive the most public and private attention in the early 90s. In 1993, its history and reputed healing properties were even highlighted on popular prime time news shows.  It was heralded as the next great natural/adjunct therapy for person’s suffering from certain forms of cancers. This optimism was the result of a long-standing belief that because sharks were composed entirely of cartilage, they could not develop malignancies. This principle, however, was dismissed by contemporary research. Sharks can develop certain forms of cancers, though the occurrence is very rare.
Shark cartilage’s predecessor, bovine sourced cartilage (BTC), has been studied since the early 1950s. Although it was never as widely publicized as shark cartilage, its usage has been studied in elongated clinical trials with much greater efficiency. Bovine sourced cartilages may provide greater benefit for individuals whom are considering beginning a supplementation program. BTC may ultimately provide for a more tolerable delivery form. Not only is it free of the adverse smells and tastes often associated with shark cartilages, far less of bovine cartilage is needed to produce effective results.
Bovine cartilage should not be confused with shark cartilage, as the two are obtained from different sources. Both products have shown great promise in the treatment of various medical conditions.
There are no natural dietary sources of cartilage within the average human diet. The ingestion of capsules and powders containing shark or bovine cartilages is the sole method in obtaining dietary sources of cartilage. Bovine cartilage is also made available through dermatological skin creams, and medicinal wound dressings.
Cartilage is a unique tissue in human physiology. Unlike other tissues located throughout the body, cartilage does not contain blood vessels. This characteristic is the reason why malignancies rarely occur on its cells. Researchers have investigated the possibilities that both shark and bovine cartilage may inhibit the angiogenesis of tumors.  Angiogenesis is the formation of new capillaries and is thought to be a determinant in the spread of various malignancies.
Matrix metalloproteases (MMPs) are enzymes secreted by tumors. These specific enzymes are thought to break down the surrounding tissue, enabling the invasive malignancy to spread.  Various proteins, which further the growth of new blood vessels and MMPs, are thought to be inhibited by the administration of cartilage containing supplements.  By limiting, or eradicating, the blood supply of tumors, cartilage may destroy certain cancerous tumors by robbing them of their oxygen supplies. Supplemental cartilage and its anti-angiogenesis activity continues to be at the forefront of research in breast, colon, lung, prostate and brain cancers. Other conditions that may benefit from cartilage’s angiogenesis inhibiting properties include; lymphoma, diabetic retinopathy, macular degeneration, and neovascular glaucoma.
Cartilage has also demonstrated moderate success in the treatment of inflammatory diseases, such as arthritis. Cartilage is a rich source of naturally occurring glucosamine and chondroitin. These two compounds have been shown to increase mobility, decrease pain, and slow the progression of certain forms of arthritis. [5, 6] Bovine cartilage, in particular, may be the most effective treatment form for arthritis sufferers. Bovine tracheal cartilages are comprised of both collagen and proteoglycans. The main constituents of the proteoglycans found in bovine cartilage comprise chondroitin sulphate.
The biological activity from both types of cartilages may provide for certain analgesic and anti-inflammatory actions in these conditions. [7, 8] Further evidence suggests that these cartilages may harness the potential to treat other inflammatory diseases, like psoriasis. Psoriasis is an immune-mediated disease which causes patches of skin to become inflamed, and is characterized by significant alterations in the blood supply to surface areas of the skin. Researchers have theorized that by preventing blood vessel growth in this disease, supplemental cartilage may decrease inflammation, thus stimulating one’s immunological response. 
Topical applications of pulverized bovine cartilage appears to stimulate wound healing.  The FDA has even approved the bovine based wound dressing, “Catrix” dressing, for the treatment and management of:
- Pressure ulcers (stages I-IV)
- Stasis ulcers
- 1st and 2nd degree burns
- Diabetic ulcers
- Post surgical incisions
- Radiation dermatitis
- Cuts, abrasions and irritations
- Partial thickness wounds
- Skin conditions associated with peristomal care 
Catrix is a combination of mucopolysaccharides, type II collagen, and other growth factors, specifically designed to stimulate the granulation in soft tissue damage.
There have been no standard dosaging guidelines set for the ingestion of commercial cartilage products. The majority of cartilage-containing supplements sold today have not been thoroughly evaluated for purity and potency. Safety is always a legitimate concern, and it is highly recommended that persons choose products from reputable manufacturers.
Some researches suggest that shark cartilage may need to be taken in extremely high dosages for optimum efficacy.  For the general supplementation of shark cartilage, recommended dosages ranging from 40 - 90 grams per day, administered over a 6 - 9 month duration are not atypical. Due to this sometimes intolerable intake, bovine cartilage may provide an alternative, and more sensible approach. As previously mentioned, bovine supplements require a much lower dosage than shark cartilage to be effective. These dosages can be as little as one-third of the total dosages recommended for shark-based cartilages.
Certain acidic juices may hinder the assimilation of certain cartilage products. Cartilage supplements should be taken on an empty stomach to maximize overall absorption. The table below depicts examples of dosages from various manufacturers:
|Form:||Condition Treated||Adults and Teenagers||Children up to age 12|
|Ground Cartilage Extract||General||80 â€“ 100 grams per day, or 1.3 grams per kg of body weight 3 â€“ 4 X per day||Not applicable|
|Ground Cartilage Extract||Psoriasis||.4 - .5 grams per kg of bodyweight until symptoms improve; Lower to Â½ this dose thereafter||Not applicable|
|Creams||Psoriasis||10 â€“ 30% cartilage based cream, applied to affected area for periods ranging from 4 â€“ 6 weeks||Not applicable|
|Ground Cartilage Extract||Arthritis||.5 â€“ 2 grams per kg of body weight, 2 â€“ 3 times daily||Not applicable|
*Because cartilage has been shown to inhibit the formation of new blood vessels, children and pregnant women should never use, or be administered, cartilage- containing supplements. 
Most side effects are minor. The most common complaints attributed with cartilage supplementation, include; bad taste , slight GI distress, weakness, dizziness, and possible constipation. Despite this relative safety, persons should also be aware of any signs signaling possible liver dysfunction. Symptoms include; extremely dark urine, widespread itchiness, pain or swelling in the upper right region of the abdomen, and a yellowing of the skin and eyes. One case of acute hepatitis has been associated with using oral shark cartilage. 
Cartilage products are often high in dietary calcium. There is some fear that it may interfere with certain calcium drugs or calcium supplements. Shark cartilage may have been a contributing factor towards the development of hypercalcemia in certain cancer patient studies.  The inclusion of dietary calcium supplements is not recommended while taking cartilage supplements.
Despite these reported interactions, the United States Food and Drug Administration (FDA) has deemed shark cartilage “non-toxic”. 
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