Glucosamine Chondroitin: Uses, Benefits, Side Effects, and Dosage

Glucosamine and chondroitin are two naturally occurring compounds within your cartilage.

Cartilage is a main type of connective tissue in your body. One of many important purposes of cartilage is to protect and cushion the ends of your bones, which is why it’s found within your joints (1, 2).

In people with osteoarthritis, this cartilage is wearing down, which can cause the bones to rub together. Over time, this can lead to pain and decreased joint mobility, commonly in the knees, hips, hands, and spine (1, 2).

Glucosamine and chondroitin, typically taken combined in a single supplement, are said to relieve arthritis pain by acting as natural anti-inflammatories and slowing down the deterioration of cartilage.

With upward of 3.6% of the global population living with this debilitating condition, many people use or have tried using combined glucosamine and chondroitin supplements to alleviate osteoarthritis pain (2).

Summary

Glucosamine and chondroitin are two compounds that occur naturally in your cartilage. Available in supplement form, they’re commonly taken together to lessen osteoarthritis pain and manage symptoms.

Glucosamine and chondroitin supplements are controversial, since many experts don’t agree on their effectiveness.

Both the American College of Rheumatology (ACR), the Arthritis Foundation, and the Osteoarthritis Research Society International (OARSI) all strongly discourage these supplements due to a lack of evidence and a high risk of bias in available studies (3, 4).

Contrarily, the European Society for Clinical and Economic Aspects of Osteoporosis (ESCEO) suggests that pharmaceutical grade — or crystalline — glucosamine and chondroitin can be used as a first-line treatment for knee osteoarthritis (4).

These mixed recommendations may partially stem from the fact that the manufacturer and type of the supplements can result in different study results. For example, pharmaceutical-grade varieties appear more effective compared with over-the-counter options (4, 5).

Summary

Despite their widespread use, glucosamine and chondroitin are controversial when used to treat osteoarthritis pain, due to conflicting research and recommendations.

There are many studies available on the use of glucosamine and chondroitin for osteoarthritis pain, though they have conflicting conclusions on the effectiveness of the supplements.

Glucosamine

Glucosamine has been extensively studied for its role in osteoarthritis pain management.

In a 2017 analysis in 1,625 people with hip or knee osteoarthritis, glucosamine supplements did not significantly improve osteoarthritis pain or function compared with a placebo (6).

On the other hand, a 2018 analysis showed small improvements in knee osteoarthritis pain with regular use of glucosamine sulfate, though the authors suggested that higher-quality data is needed (7).

Also, a 2-year cohort study found a 36% reduction in nonsteroidal anti-inflammatory drug (NSAID) use when taking 1,500 mg of crystalline glucosamine daily (8).

In the same study, 1250 mg/day of glucosamine hydrochloride, 1,200 mg/day of chondroitin sulfate, 100 mg/day of diacerein, 300 mg/day of avocado-soybean unsaponifiable (ASU), and a placebo didn’t change NSAID use (8).

Finally, a 2 1/2-year study in 407 women with overweight ages 50–60 found 1,500 mg/day of glucosamine sulfate to significantly decrease the risk of knee osteoarthritis compared with a placebo, suggesting that it may work as a preventive therapy (9).

Chondroitin

Chondroitin has also been well studied as a remedy for osteoarthritis symptom management.

A 2017 double-blind, randomized study in 604 participants with knee osteoarthritis compared the effects of taking 800 mg/day of chondroitin sulfate, 200 mg/day of a popular NSAID known as celecoxib, and a placebo on osteoarthritis pain management (10).

After 6 months, chondroitin sulfate led to similar pain scores as celecoxib and significantly lower scores than the placebo. Thus, the authors concluded that chondroitin sulfate may be an effective pain remedy for those with knee osteoarthritis pain (10).

In a 2014 review of 43 studies on the use of chondroitin for osteoarthritis, chondroitin taken alone or with glucosamine showed significantly lower pain scores — with a 10% mean difference — compared with a placebo. However, the overall quality of studies was low (11).

In the same review, the supplement was not found to improve joint mobility or function compared with a placebo (11).

Glucosamine and chondroitin together

Though the two can be taken separately, glucosamine and chondroitin are commonly taken as a single supplement. This combination has been more extensively studied.

A 2015 2-year double-blind, randomized study showed no differences in pain or joint space narrowing — a sign of cartilage deterioration — after taking either 1,500 mg/day of glucosamine sulfate, 800 mg/day of chondroitin sulfate, a combination of both, or a placebo (12).

Similar results were observed in a 2018 analysis, where combined glucosamine and chondroitin didn’t significantly improve pain or stiffness. Meanwhile, chondroitin alone led to minor improvements in pain (13).

On the other hand, another 2018 analysis observed a significant improvement in pain scores when glucosamine and chondroitin were taken together, while no improvements were found when the supplements were taken separately (14).

Similarly, a 2015 sponsored study showed that combining 1,500 mg of glucosamine hydrochloride with 1,200 mg of chondroitin sulfate effectively reduced knee osteoarthritis pain, stiffness, and swelling compared with 200 mg of the osteoarthritis NSAID celecoxib (15).

Another 2015 study also found that combined glucosamine and chondroitin supplements were comparably effective as celecoxib (16).

Ultimately, no firm conclusions can be made on the effectiveness of glucosamine, chondroitin, or the two combined as a treatment for osteoarthritic pain or stiffness. Due to the large inconsistency in results and quality of available research, continued research is needed.

Summary

Taken together or individually, both glucosamine and chondroitin may provide minor relief from osteoarthritis pain. However, not all studies have shown them to be beneficial, and more research is needed.

Most studies have shown that both glucosamine and chondroitin are safe to use for most people and no serious side effects have been reported. Only mild side effects like stomach upset, nausea, and headache have been observed (13, 17).

However, keep in mind that glucosamine is commonly derived from chitin — a compound found in shellfish. Therefore, those with a shellfish allergy should read the label carefully and opt for varieties made from cows or pigs (17).

Glucosamine may also be made from a fungus or fermented corn. And due to the animal origin of some ingredients, the supplements may not be suitable for those following a vegan or vegetarian dietary pattern.

Finally, it’s postulated that glucosamine and chondroitin supplements may affect blood sugar levels, reduce insulin sensitivity, and interact with anticoagulant medications likes Warfarin. That’s why you should consult a healthcare professional before trying them (17).

Summary

Generally, glucosamine and chondroitin are considered safe, though they may not be suitable for those with shellfish allergies, diabetes, or taking anticoagulant medication. Talk with a healthcare professional first.

Due to the conflicting data on the effectiveness of glucosamine and chondroitin, no standard recommendations are available.

That said, studies that have observed improvements in osteoarthritis symptoms routinely used dosages of 1,500 mg glucosamine sulfate and 1,200 mg chondroitin sulfate, which can be obtained over the counter (14, 15, 16).

However, it’s best to first consult a healthcare professional, who can provide recommendations tailored to you and your health.

Summary

Some studies have found 1,500 mg of glucosamine sulfate and 1,200 mg chondroitin sulfate to be the most effective. However, due to conflicting research, general recommendations cannot be made.

Glucosamine and chondroitin are popular supplements used to alleviate osteoarthritis pain.

Their use remains controversial, however, due to conflicting research. While some studies have shown that taking glucosamine and chondroitin supplements may reduce pain and stiffness, others have found that they provide no benefits.

The supplements are considered safe for most people, except for those with shellfish allergies, with diabetes or metabolic disorders, or taking anticoagulant medications.

If you’re interested in trying glucosamine and chondroitin, speak with a healthcare professional first to determine whether it’s right for you.