Cartilage is a type of connective tissue consisting of cells called chondrocytes and a tough, flexible matrix made of collagen, protein, and sugar. Most cartilage is converted to bone as an animal matures, but some cartilage remains in the nose and ears, as well as joints such as the knees, hips, shoulders, and fingers.

Bovine cartilage (cartilage derived from cows) and shark cartilage have been investigated for many years as treatments for cancer, psoriasis, arthritis, and a number of other medical conditions. The interest in cartilage as a treatment for cancer arose, at least in part, from the mistaken belief that sharks (whose skeletons consist primarily of cartilage) are not affected by cancer. This assumption proved to be untrue, however, and studies in humans have yet to demonstrate that shark cartilage reverses, prevents, or even slows cancerous tumor growth.

Claims that cartilage may be of some medical value date back to 1954. Laboratory and animal studies have shown that substances in cartilage (particularly shark cartilage) may reduce inflammation associated with arthritis (including rheumatoid arthritis), stimulate the immune system, and relieve pain. Whether these beneficial properties apply to people has not been proven in scientific studies. Cartilage does appear to provide some benefits for the following health conditions:

Psoriasis

Preliminary evidence suggests that extracts of shark cartilage may reduce inflammation from psoriasis (a skin disorder that appears as raised, reddish-pink areas covered with silvery scales and red borders).

Osteoarthritis

Two components of cartilage, glucosamine and chondroitin (although not specifically cartilage supplements), have been shown to decrease pain, improve range of motion, reduce swelling, enhance walking pace, and slow the progression of osteoarthritis. Further studies are currently underway to determine if these supplements are safe and effective when taken for long periods of time.

Cancer

Despite a lack of substantial scientific evidence, shark cartilage has also been widely touted as a treatment for cancer. Because cartilage cells do not have any blood vessels, some researchers speculate that they produce substances that inhibit blood vessel formation. Cancerous tumors rely on blood vessels to survive because blood provides oxygen and nutrients necessary for their growth. The possibility that cartilage could the formation of blood vessels and "starve" cancerous tumors of necessary oxygen and nutrients has led to theories regarding the use of this supplement for cancer.

Although many studies have been conducted on cartilage as a treatment for cancer, only a few have been published in scientific journals and none have shown any benefit in using cartilage supplements for cancer (including breast, colon, lung, prostate, brain, and lymphoma). According to the National Cancer Institute (NCI), the evidence so far is inconclusive regarding the effectiveness of cartilage as a cancer treatment in humans. In fact, the NCI halted their own research regarding cartilage supplementation because all of the preparations were contaminated and the Federal Trade Commission (FTC) has taken legal action against several companies selling cartilage products as a "cancer cure."

Cartilage is not available through dietary sources. It can only be obtained though commercial preparations.

Cartilage is available in powdered form or in capsules that contain the powder. It is also available as a topical cream.

Pediatric

Cartilage should not be taken by children.

Adult

Most manufacturers' labels list a dosage of 750 mg three to four times per day.

Because of the potential for side effects and possible interactions with medications, dietary supplements should only be taken only under the supervision of a knowledgeable healthcare provider.

Shark and/or bovine cartilage should always be purchased from a reputable manufacturer to reduce the risk of contamination.

Labels should be checked carefully. Only supplements that contain 100% pure shark cartilage should be purchased.

Cartilage supplements should always be white. Products of any other color could indicate contamination and should therefore be avoided.

Shark cartilage products often have a strong fish odor and flavor which can be unpleasant. Large doses may cause nausea.

There has been at least one case of hepatitis reported from taking shark cartilage.

Pregnant and breastfeeding women, children, and individuals recovering from surgery and/or a heart attack should not take cartilage supplements.

Cartilage should never be used as a substitute for conventional treatments.

If you are currently being treated with any of the following medications, you should not use cartilage supplements without first talking to your healthcare provider.

Thiazide Diuretics

Cartilage contains high amounts of calcium. Thiazide diuretics, such as hydrochlorothiazide, can raise calcium levels in the blood. Therefore, using cartilage supplements together with this type of diuretic could lead to dangerously high levels of calcium.

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