Glucosaminsulfate and Chondroitin
sulfate for joints
Many older swimmers are probably
already taking either glucosamine sulfate or chondroitin sulfate or both.
What is glucosamine sulfate?
Glucosamine sulfate is a basic building
block used by the body to make cartilage, as well as tendons, ligaments, skin,
heart valves, bone, and synovial fluid (joint fluid). It is also one of the
molecules used by the body to synthesize chondroitin sulfate. Most of the
research has focused on glucosamine sulfate and joints.
Joints are the intersection of two
bones whose ends are covered in cartilage. The joint capsule surrounds the two
bony ends and has an inner synovial lining that secretes synovial fluid to
protect and lubricate the cartilage ends. Ligaments provide stability by
connecting bone to bone and lie outside the joint capsule. Tendons connect
muscle to bone.
What is chondroitin sulfate?
Chondroitin sulfate is a larger
molecule used by the body to make cartilage, ligaments, tendons, and bone.
Glucosamine is one of its building blocks. Like glucosamine, chondroitin
sulfate has been studied mainly in its role with joints.
What is arthritis?
Arthritis is generally an acute
inflammation of a joint. The most common form of arthritis is osteoarthritis,
or degenerative joint disease (DJD). This is the arthritis of aging and its
symptoms are felt in the joints. By age forty, 90% of the population will have
some degree of degenerative joint disease, including decreased joint space and
bone spurs (osteophytes), but not everyone will have symptoms. A feeling of stiffness in the joints in the
morning is a typical sign of arthritis.
Knees, hips, hands, fingers, lower back, and neck are the joints most
commonly affected.
How do glucosamine sulfate and chondroitin sulfate
work?
Radiographs of joints affected
by DJD show joint space narrowing. In
reality, this is a decrease in the thickness of the cartilage around the ends
of the bones. Cartilage is made by cells called chondrocytes. As we age, the
chondrocytes produce less cartilage. Glucosamine sulfate increases production
of cartilage in two ways. First, the
chondrocytes use it directly as raw material to make more cartilage. Secondly, glucosamine sulfate stimulates the
chondrocytes to manufacture more cartilage and to replace unhealthy cartilage
with fresh, healthy cartilage. Healthy cartilage, in turn, allows more good
nutrients to reach the chondrocytes, and thus continue the cycle of creating
more healthy cartilage. Glucosamine
sulfate also inhibits the breakdown of cartilage.
While less research has been done on
chondroitin sulfate, it too appears to help the joints, by increasing the
viscosity and amount of joint fluid (hyaluronic acid), inhibiting the breakdown
of cartilage, and reducing joint inflammation.
How does glucosamine sulfate compare to
non-steroidal anti-inflammatory drugs?
Studies have shown that patients who
take non-steroidal anti-inflammatory drugs (NSAIDs) felt better initially, but
after three to six weeks, the group on glucosamine sulfate felt better. While
they reduce pain and inflammation, NSAIDs inhibit the production of new
cartilage. This prevents the joints from healing and improving. When NSAIDs and glucosamine sulfate are taken
together, joints did not deteriorate as rapidly as when only NSAIDs are taken.
What kind of
supplements are most effective?
Both glucosamine sulfate and
glucosamine hydrochloride supplements are sold.
Although the manufacturers of glucosamine hydrochloride say that there
is no difference between the two, all the studies showing positive effects were
with glucosamine sulfate, and no studies to date have shown that the
hydrochloride works. For that reason, if you are purchasing glucosamine, make
sure it is glucosamine sulfate and not glucosamine hydrochloride. 90% of
glucosamine sulfate is absorbed.
Purified chondroitin sulfate is
absorbed by the human gastrointestinal tract, but probably not nearly as well
as glucosamine sulfate. Purified chondroitin sulfate is very expensive.
Consumerlab.com, which tests natural
food store supplements, found that most supplements labeled glucosamine do
contain glucosamine. However, supplements containing a combination of
glucosamine and chondroitin generally do not contain chondroitin in amounts
considered effective. Generally
supplements available to professionals, such as chiropractors and naturopathic
doctors, are more consistently of higher quality. If you buy your
supplements from a health food store, check the consumerlab.com website first
for the most effective products.
What about dosing, side effects, and
contraindications?
The average dose for glucosamine
sulfate is 1500 mg per day and for chondroitin sulfate 1200 mg. It can be taken in one dose, or split into
several doses. Side effects for both
supplements are minimal, particularly when compared to NSAIDs, and consist
primarily of digestive complaints. People who are highly sensitive to shellfish
might want to avoid glucosamine sulfate, since it is manufactured from
shellfish, but no known adverse cases have been reported. Diabetics should discuss glucosamine with
their doctors before taking it, and should be careful to monitor their blood
sugar initially. As with any supplement,
stop taking it if it makes you feel bad.
Some final thoughts
While most of the research on
glucosamine sulfate has been done on DJD, I have found that it helps in healing
swimming and other sports related injuries. This makes sense, as it is a
building block for tendons and ligaments.
It is particularly helpful in cases of knee injuries because of its
healing effect on the knee cartilage and the cartilaginous menisci of the knee.
For acute injuries, I would recommend 1500 mg per day until the injury has
healed.
Dr. Jessica Seaton is a chiropractic orthopedist in private
practice in