Overview

Shark cartilage refers to the cartilage from certain ocean sharks, including the dogfish and hammerhead sharks. It contains many different chemicals and substances, including proteins, fats, minerals, and glycosaminoglycans. Although there is interest in using shark cartilage for various purposes, its benefits for any use are not well defined. Common side effects may include nausea, vomiting, constipation, diarrhea, or an upset stomach. Before taking shark cartilage, tell your health care provider about all your health conditions and any medicines or supplements you may be using.

Uses

What is shark cartilage used for?

Shark cartilage is used for various reasons, but its benefits for any use are not well defined. Some common reasons why people use shark cartilage include the following.

• Cancer
• Joint problems
• Psoriasis

Note: The FDA has not reviewed shark cartilage for safety and effectiveness, and it is not approved by the FDA. Learn more about dietary supplements here.

How does shark cartilage work (mechanism of action)?

Cartilage is the smooth, strong substance that covers the ends of your bones, allowing them to rub up against each other without causing damage. It contains many different substances, including proteins, fats, and glycosaminoglycans. Cartilage is found in humans and many animals, but most cartilage supplements come from cows (bovine cartilage) and sharks.

Shark cartilage usually comes from certain ocean sharks, including the dogfish and hammerhead sharks. The most common protein in shark cartilage is collagen[1] , and the most common glycosaminoglycan is a substance called chondroitin[2] . Shark cartilage also contains minerals, including calcium, and various chemicals. Some of the chemicals in shark cartilage have an antiangiogenic effect, meaning that they may help block the growth of blood vessels.

Supplements that contain shark cartilage are often promoted for cancer treatment due to two popular theories. The first is an unproven theory that some chemicals in the cartilage may stop blood vessels from growing around cancer cells, causing them to die. The second is a disproven (false) theory that sharks cannot develop cancer. Despite many years of interest in shark cartilage supplements, there is still very little research on their use for cancer, and their benefits are not well defined. You should not rely on shark cartilage as a cancer treatment.

Some shark cartilage products are also marketed for other uses, such as joint problems and psoriasis, but it is not clear if or how shark cartilage may work for these uses.

Natural products like shark cartilage contain many different substances, including collagen and chondroitin. The actual contents and effects of shark cartilage may vary depending on the shark that it came from and how it was processed.

How should I store shark cartilage?

You should store shark cartilage according to the product label. Most dietary supplements should be kept in a cool, dry location that is out of the reach of children and pets and not in direct sunlight.

Side Effects

What are the most common side effects of shark cartilage?

The most common side effects of shark cartilage are listed below. These side effects may vary depending on the dose you are taking or the specific product you are using. Tell your health care provider if you have any of these side effects that bother you.

• Constipation or diarrhea
• Nausea or vomiting
• Upset stomach

There may be other side effects of shark cartilage that are not listed here. Contact your health care provider if you think you are having a side effect of a supplement. In the U.S., you can report side effects to the FDA at www.safetyreporting.hhs.gov or by calling 888-SAFEFOOD (888-723-3366). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of shark cartilage?

While less common, the most serious side effects of shark cartilage are described below, along with what to do if they happen.

Severe Allergic Reactions. Shark cartilage may cause allergic reactions, which can be serious. Stop using shark cartilage and get help right away if you have any of the following symptoms of a serious allergic reaction.

• Breathing problems or wheezing
• Racing heart
• Fever or general ill feeling
• Swollen lymph nodes
• Swelling of the face, lips, mouth, tongue, or throat
• Trouble swallowing or throat tightness
• Itching or skin rash
• Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
• Nausea or vomiting
• Dizziness, feeling lightheaded, or fainting
• Stomach cramps
• Joint pain

Precautions

Who should not use shark cartilage?

Allergies to Ingredients. People who are allergic to any of the following should not use shark cartilage.

• Shark cartilage
• Any of the ingredients in the specific product

Your pharmacist can tell you all of the ingredients in the specific shark cartilage products they stock.

What should I know about shark cartilage before using it?

Shark cartilage is a dietary supplement. It cannot be marketed to treat or cure a disease.

Read and follow the directions on the specific product you are using, or use it as recommended by your health care provider.

Keep shark cartilage out of the reach of children.

If you are using shark cartilage powder, use an appropriate measuring device to measure the powder, such as the device included with the product. Read the label carefully and measure the amount stated on the label.

Shark cartilage, which comes from sharks, naturally contains many different substances, including proteins, glycosaminoglycans, fats, minerals, and various chemicals. The actual substances found in each batch of shark cartilage may depend on the specific shark that the cartilage was obtained from. It may also depend on the way that the cartilage was obtained and processed. If you switch to a new bottle or a different brand, you may not have the same effects or side effects because of this variability. Talk to your health care provider if you have questions or concerns.

The FDA has not tested shark cartilage products to confirm that they contain the ingredients stated on their labels. Some dietary supplements have been tested by third-party organizations to confirm that they contain the ingredients listed on their labels and do not contain any harmful chemicals. Learn more about how to choose a safe dietary supplement product here.

What should I tell my health care provider before using shark cartilage?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if shark cartilage is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions.Tell your health care provider if you have any of the following.

• Asthma
• Cancer
• High calcium levels (hypercalcemia)
• Kidney or liver problems

Pregnancy. It is not known if or how shark cartilage could affect pregnancy or harm a fetus. Tell your health care provider if you are pregnant or plan to become pregnant.

Breastfeeding. It is not known if shark cartilage passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.

Interactions

Does shark cartilage interact with foods or drinks?

There are no known interactions between shark cartilage and foods or drinks.

It is unknown if drinking alcohol will affect shark cartilage.

Does shark cartilage interact with medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

The interactions between shark cartilage and medicines are not fully understood. As with most dietary supplements, research on drug interactions with shark cartilage is incomplete. Always check with your health care provider before taking shark cartilage with any medicines.

Dosing

What should I do if I accidentally use too much shark cartilage?

If you or someone else has used too much shark cartilage, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

Shark cartilage is available in various forms and doses. Read the product label closely and speak to a health care provider about how to take shark cartilage safely. Do not take double or extra doses, even if you miss a dose.