You know it’s in your ears and nose and sharks are made almost entirely of it — but there’s a lot about cartilage that most people don’t know. The flexible, yet tough connective tissue can be found throughout the body, and though it’s true that it’s slow to repair itself once damaged, science knows more than ever before how to best promote healthy cartilage. Here are the top things you never knew about the tissue that allows you to do all the things you love.
1. There are three types
Not all cartilage is the same, nor does it serve the same purpose within the body.
Hyaline cartilage is the cartilage in your nose and ear canal, and it’s the form found most often in the human body. It also has a high concentration of collagen, which allows it to give structure to body parts while providing some elasticity as well. It is smooth and allows bones in the joints throughout the body to glide during movement. This type of cartilage is also found at the end of each of the ribs, various bone surfaces at the joints, and in the trachea and larynx. It’s known as being like a shock absorber and provides cushioning in the joints.
Elastic cartilage is, as you may have guessed, the most flexible of the three types. Elastin fibers give this type of cartilage the ability to snap back into place after being stretched, making it ideal for the exact places it is found in the body: the outer ear (think about the many ways your ear can bend and fold, and then return to its normal shape), and epiglottis (the elastic cartilage here allows us to swallow without food aspiration, and makes breathing possible).
Fibrous cartilage is a tough and firm type of cartilage that is found at the knee joint in the meniscus, as well as between vertebrae and in the temporal mandibular joint, where your jaw connects to your skull. It is found in soft tissue to bone attachments as well as the pubic symphysis joint, which help connect your hips. The fibers in this form of cartilage are very dense, and by nature this form is also the most rigid of the cartilage types.
2. Cartilage can determine your future height during childhood
Ever wonder how a pediatrician can predict a child’s height with such confidence? It turns out that cartilage holds the answer.
“The growth rate between your cartilage and bones can determine how tall you will be” says Allen Conrad, BS, DC, CSCS. “When the cartilage grows faster than bone near the growth plates, the person will be very tall once they are fully grown. If the bone growth during adolescence is faster than the cartilage growth, the person will be shorter. Once you are an adult, cartilage growth is very insignificant.”
3. Cartilage has no direct blood supply
Much of the human body relies on access to adequate blood supply, with the exception of cartilage.
“As we age, cartilage is replaced in the body much slower than other cells because it is avascular, meaning it has no direct blood supply,” says Dr. Conrad. “This is why cartilage injuries over age 40 become very problematic for runners, due to the inflammatory and degenerative process of arthritis. You aren’t replacing significant cartilage once it’s damaged because the flexible fibers in cartilage don’t regenerate like skin cells do. This is why high impact exercises are not recommended for those over 40 with cartilage damage or arthritic knees.”
4. Cartilage has no nerves
If you have joint discomfort, it’s most likely due to the lack of cartilage in your joints.
“Cartilage is also aneural, which means it has no nerves that give any sensation; if you cut through cartilage with a knife it would be completely numb,” says Dana Piasecki, MD, co-founder of the Cartilage Restoration Institute at OrthoCarolina. “When patients lose cartilage, the discomfort that results is not from the cartilage but instead is from the bone underneath, which has lost the protection of the cartilage.”
In fact, the role cartilage plays in promoting comfort is quite incredible.
“Cartilage is one of the most unique and remarkable tissues in the body,” says Dr. Piasecki. “The specific type of cartilage which lines our joints has the ability to decrease friction 1000 times more than two pieces of ice rubbed against one another.”
5. Cartilage can’t fix itself
Because cartilage can’t fix itself and we don’t grow much more of it after childhood, the cartilage wear and tear you receive in childhood will follow you into adulthood.
“Cartilage has very little blood supply, which has two important consequences for injuries to the joint,” says Dr. Piasecki. “First, since the body’s method of repairing tissue starts with having blood vessels to access a damaged area, cartilage cannot repair itself. Abrasions or breaks in the cartilage in childhood will remain that way throughout a patient’s life. The second implication is that the body’s immune system, which also uses blood vessels to get where it needs to go, doesn’t have access to cartilage. This allows us to restore lost cartilage using transplants from donors, without the fear of rejection or the need for immunosuppressive medications.”
6. Cartilage health declines over time
Cartilage is 85 percent water for most adults, but 70 percent in the elderly. But its decline isn’t inevitable.
“While cartilage cannot replace itself, localized cartilage loss has several management options. In fact, most cartilage defects can be managed without surgery,” says Dr. Piasecki
One non-surgical option to promote joint comfort and support healthy cartilage is a glucosamine and chondroitin supplement, like Cosamin®DS. Clinically Proven to Help Promote Joint Comfort & Mobility. Cosamin®DS is the No. 1 researched glucosamine and chondroitin brand.* One serving contains 1,500 mg of glucosamine HCl and 1,200 mg of chondroitin sulfate, the same amount of ingredients proven to be effective in published clinical studies. At the cellular level, the ingredients in Cosamin®DS work together to inhibit enzymes that break down cartilage.
*Based on U.S. studies published in peer-reviewed journals, the Cosamin® brand is the most researched glucosamine/chondroitin sulfate brand.