Glucosamine, which is produced naturally in the body, plays a key role in building cartilage, the tough connective tissue that cushions the joints.
Glucosamine sulfate is a naturally occurring chemical found in the human body. It is in the fluid that is around joints. Glucosamine is also found in other places in nature. For example, the glucosamine sulfate that is put into dietary supplements is often harvested from the shells of shellfish. Glucosamine sulfate used in dietary supplements does not always come from natural sources. It can also be made in a laboratory.
Several scientific studies suggest that glucosamine may be an effective treatment for osteoarthritis (OA). Osteoarthritis is a type of arthritis that occurs when cartilage breaks down and is lost, either due to injury or to normal wear and tear. It commonly occurs as people age. In some studies, glucosamine supplements have decreased the joint pain of OA. Not all studies are positive, however, and several recent ones have not found any positive effect from taking glucosamine. It's not clear why the studies have conflicting results, and experts disagree on whether glucosamine is helpful in treating OA.
In the past, some researchers thought glucosamine may actually slow progression of the disease, unlike other current medical treatments for OA. Many people take either acetaminophen (Tylenol) or nonsteroidal anti-inflammatory drugs, such as ibuprofen (Advil, Motrin) and naproxen (Aleve), for OA pain. In addition, some of these drugs can cause stomach upset, cramps, constipation, diarrhea, and in some cases, stomach ulcers and infertility.
But so far studies have not shown conclusively that glucosamine helps repair or grow new cartilage, or stops cartilage from being further damaged. Glucosamine is often taken with chondroitin, another supplement thought to be effective in treating OA. Like glucosamine, chondroitin also has conflicting results in studies.
To complement glucosamine benefits, arthritis sufferers often take chondroitin sulfate, also a naturally occurring compound. In addition, to obtain full glucosamine benefits and to avoid any glucosamine side effects, always purchase supplements, glucosamine or otherwise, from reputable manufacturers with a proven history of quality.
To read more about Glucosamine Chondroitin, click here.
Glucosamine is naturally present in the shells of shellfish, animal bones and bone marrow. It is also present in some fungi, such as Aspergillus niger.
Glucosamine was first prepared in 1876 by Georg Ledderhose by the hydrolysis of chitin with concentrated hydrochloric acid. The stereochemistry was not fully defined until the 1939 work of Walter Haworth. D-Glucosamine is made naturally in the form of glucosamine-6-phosphate, and is the biochemical precursor of all nitrogen-containing sugars. Specifically, glucosamine-6-phosphate is synthesized from fructose 6-phosphate and glutamine by glucosamine-6-phosphate deaminase as the first step of the hexosamine biosynthesis pathway. The end-product of this pathway is Uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), which is then used for making glycosaminoglycans, proteoglycans, and glycolipids.
As the formation of glucosamine-6-phosphate is the first step for the synthesis of these products, glucosamine may be important in regulating their production; however, the way that the hexosamine biosynthesis pathway is actually regulated, and whether this could be involved in contributing to human disease remains unclear.
Arthritis sufferers have touted glucosamine benefits for years, and more research is pointing to its efficacy as an effective treatment for osteoarthritis and rheumatoid arthritis.
Glucosamine benefits the body, because it occurs naturally in human tissues, making it a viable alternative to the synthetically derived drugs that have infiltrated the market in past years. Like glucosamine, these drugs known as NSAIDs, or nonsteroidal anti-inflammatory drugs, can help relieve the discomfort associated with arthritis; however, they work in vastly different ways.
The problem with NSAIDs, such as the now infamous Vioxx, is that they can increase the risk of heart attacks and gastrointestinal bleeding, according to the United States Food and Drug Administration. The FDA even targeted non-prescription NSAIDs such as Ibuprofen by advising manufacturers to revise their labeling and provide more specific information about the potential cardiovascular and gastrointestinal risks of their individual products. Glucosamine side effects are minimal in comparison.
So, how exactly is glucosamine, an amino sugar, different from NSAIDs and what are the proven glucosamine benefits?
Instead of tricking the body into not receiving pain signals, glucosamine goes straight to the cause of the disease. Studies indicate that glucosamine benefits tender joints by stimulating the production of proteins, which aid in the building and repairing of connective tissue in the body. As we grow older, our body's ability to produce glucosamine decreases, and our structural system pays the price. Because osteoarthritis, in particular, is often caused by age and wear, glucosamine benefits the body by possibly slowing or reversing the progression of the disease.
A 6-month double-blind, multicenter trial has been recently performed to assess the efficacy of glucosamine sulfate 1500 mg once daily compared to placebo and acetaminophen in patients with osteoarthritis of the knee (GUIDE study) - it was published in 2007. The abstract of the publication reads: “At baseline, the study patients had moderately severe OA symptoms (mean Lequesne index approximately 11 points). Glucosamine sulfate was more effective than placebo in improving the Lequesne score, with a final decrease of 3.1 points, versus 1.9 with placebo (difference between glucosamine sulfate and placebo -1.2 [95% confidence interval -2.3, -0.8]) (P = 0.032). The 2.7-point decrease with acetaminophen was not significantly different from that with placebo (difference -0.8 [95% confidence interval -1.9, 0.3]) (P = 0.18). Similar results were observed for the WOMAC. There were more responders to glucosamine sulfate (39.6%) and acetaminophen (33.3%) than to placebo (21.2%) (P = 0.004 and P = 0.047, respectively, versus placebo). Safety was good, and was comparable among groups.”
A 2009 scientific review of available studies concluded that glucosamine sulfate, “glucosamine hydrochloride, and chondroitin sulfate have individually shown inconsistent efficacy in decreasing arthritis pain”, though “many studies confirmed pain relief with glucosamine and chondroitin sulfate in combined use”.
However, currently OARSI (OsteoArthritis Research Society International) is recommending glucosamine as the second most effective treatment for moderate cases of osteoarthritis. Likewise, recent European League Against Rheumatism practice guidelines for knee osteoarthritis grants to glucosamine sulfate the highest level of evidence, 1A, and strength of the recommendation, A.
Use of glucosamine in veterinary medicine is seemingly accepted, but there is no proof of efficacy and the quality of published clinical trials of glucosamine in horses was recently judged too low to be of any value in guiding treatment of horses.
Results from several well designed scientific studies suggest that glucosamine supplements may be an effective treatment for OA, particularly OA of the knee or hip. In general, these studies suggest that glucosamine:
Reduces OA pain
Improves function in people with hip or knee OA
Reduces joint swelling and stiffness
Provides relief from OA symptoms for up to 3 months after treatment is stopped
However, the largest clinical trial so far, the 2006 Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), sponsored by the National Institutes of Health, showed conflicting and somewhat confusing results. The study of about 1,600 people with OA of the knee found that glucosamine alone, or in combination with chondroitin did not reduce pain in the overall group, although it did appear to lessen pain among those with moderate to severe OA of the knee. The study has raised questions for further research. Researchers are now studying whether the glucosamine chondroitin combination may in fact help those with more severe OA.
A second phase in 2008 looked at some participants who continued with the study for another 28 months. They were tested to see whether glucosamine or chondroitin (together or alone) slowed the loss of cartilage in their knees. They showed no difference in cartilage loss compared with people who took placebo. But all groups -- those taking placebo, those taking both supplements, and those taking only one supplement -- lost less cartilage than expected.
Most studies show that glucosamine needs to be taken for 2 - 4 months before it is effective, although you may experience some improvement sooner. Glucosamine and chondroitin can be used along with nonsteroidal anti-inflammatory drugs (NSAIDs) to treat OA.
Crohn's disease and ulcerative colitis are two inflammatory bowel diseases marked by chronic, frequent bloody diarrhea. Some preliminary clinical evidence suggests that N-acetyl glucosamine oral supplements or enemas may help improve symptoms of IBD in children who have not improved with standard medical treatment. However, the study was small and lacked a control group, so it is impossible to say whether glucosamine really worked. More research is needed.
Clinical studies have consistently reported that glucosamine appears safe. However, a recent Université Laval study shows that people taking glucosamine tend to go beyond recommended guidelines, as they do not feel any positive effects from the drug. Beyond recommended dosages, researchers found in preliminary studies that glucosamine may damage pancreatic cells, possibly increasing the risk of developing diabetes.
Adverse effects, which are usually mild and infrequent, include stomach upset, constipation, diarrhea, headache and rash.
Since glucosamine is usually derived from the shells of shellfish while the allergen is within the flesh of the animals, it is probably safe even for those with shellfish allergy. Alternative sources using fungal fermentation of corn are available.
Another concern has been that the extra glucosamine could contribute to diabetes by interfering with the normal regulation of the hexosamine biosynthesis pathway, but several investigations have found no evidence that this occurs. A manufacturer-supported review conducted by Anderson et al. in 2005 summarizes the effects of glucosamine on glucose metabolism in in vitro studies, the effects of oral administration of large doses of glucosamine in animals and the effects of glucosamine supplementation with normal recommended dosages in humans, concluding that glucosamine does not cause glucose intolerance and has no documented effects on glucose metabolism. Other studies conducted in lean or obese subjects concluded that oral glucosamine at standard doses does not cause or significantly worsen insulin resistance or endothelial dysfunction.
Because of the potential for side effects and interactions with medications, dietary supplements should be taken only under the supervision of a knowledgeable health care provider.
Studies suggest that glucosamine is safe, and causes only minor side effects, such as stomach upset, heartburn, indigestion, gas, bloating, nausea, and diarrhea. If these occur, try taking glucosamine with food. People with peptic ulcers should take glucosamine sulfate with food.
Glucosamine sulfate may contain high amounts of sodium or potassium. People on a restricted diet or who take potassium sparing diuretics should carefully check the label before taking glucosamine supplements.
People with diabetes should have their blood sugar checked regularly. Glucosamine may cause insulin to work less effectively.
Some glucosamine supplements are made from shellfish, so people with shellfish allergies should check with a health care professional before taking them.
Pregnant and breastfeeding women should hear with their healthcare provider, since it has not been studied for safety in these groups.
Glucosamine may raise blood pressure and cholesterol levels. See your doctor regularly to have these levels checked while you are taking glucosamine.
There is some concern that glucosamine may increase exacerbations in some patients with asthma.
If you are currently being treated with any of the following medications, you should not use glucosamine or make any adjustments to your medications without first talking to your healthcare provider.
Warfarin (Coumadin) -- Glucosamine may increase the blood thinning effect of coumadin and may increase the risk of bruising or bleeding, which can be serious. Speak with your physician.
Nonsteroidal anti-inflammatory drugs (NSAIDs) -- If you take NSAIDs to relieve the pain of OA, taking glucosamine may reduce the dose of NSAIDs you need to take. Since NSAIDs can cause stomach bleeding, reducing the dosage can be helpful. Talk to your doctor, however, before starting to take glucosamine, since it can take several months before you experience any improvements.
Blood sugar lowering medications or insulin -- Glucosamine may change the dose needed for blood sugar lowering medications and insulin. If you take these medications for diabetes, talk to your doctor before taking glucosamine.
Doxorubicin, Etoposide and Teniposide -- Glucosamine may interact negatively with these drugs.
A good product May 26, 2011, By Novella Maia From Colorado
I use this with MSM for arthritis, and am very pleased with the results.
Your joints will thank you. September 15, 2011, From Canada
GLucosamine sulfate helps to maintain and rebuild joint cartilage. You don't realize how helpful this supplement is until you stop taking it then you feel it. You can also help the muscles surrounding your joints stay strong by working out with weight bearing exercises. Free weights are good for this and the benefit is increased bone density.
It's helpful September 27, 2011, By Tai Rico From Hong Kong
... the products can help my old friend, she was 81 year old, she said it made her no pain for her knee.
Works great!!! September 01, 2010, By Mike Joe
I have many joints problems, both of my knees are injuried. I have an injury in my left knee, which made my life really misrable. NSAIDs didn't do any good, so little actually. Since I started taking glucosamine the pain was reduced to 60%, but of course with other natural supplements the pain was reduced to ZERO. Thanks for a great product!!!
Reviewer: Judy, 55-64 Female on Treatment for 1 to less than 2 years (Consumer)
Comment: Seems to have worked in the early stages of hip issues. As hip arthritis progressed - not much help.
Excellent April 13, 2011, From Washington
Seems to be working well in combination with SAMe and MSM for hip joint deterioration and pain. Should this supplement regimine prove successful over time in rejuvinating healthy cartlidge, I hope to avoid hip replacement surgery. A sodium free tablet is greatly appreciated. ...
Help for my knees January 23, 2007, From California
I have had trouble with my knees for the past few years and taking this product has really helped. My knees feel much better.
... glucosamine sulfate 1000 October 12, 2007, From North Carolina
I find that 1000 mg/2x/day has made a world of difference in my shoulders and hands
Reviewer: smsjburns, 35-44 Female on Treatment for 1 to 6 months (Consumer)
Comment: Since starting glucosamine, my knee pain is at least 50% reduced. Yesterday I walked up the stairs for the first time is 6 months. (not without some pain, but I was able to do it) I hope this is safe long-term because the last 30 days have been an enormous relief! Some diarrhea side effect, but manageable.
Reviewer: tito, 65-74 Female on Treatment for 2 to less than 5 years (Consumer)
Comment: I HAVE TAKEN 1 TABLET FOR SEVERAL YEARS BUT CHANGED TO 2 TABLETS ABOUT 5 MONTHS AGO. HAS ANYONE EVER EXPERIENCED MUSCLE DISCOMFORT FRoM USING "GLUCOSAMINE ... 1500 mg W/CHONDROITIN SULFATE 1200mg ...-I started taking 2 tablets a day when I noticed my leg muscles hurting. It may just be coincidence!
Reviewer: procosamine, 55-64 Female on Treatment for 2 to less than 5 years (Consumer)
Comment: I have osteoarthritis(knee). Five years ago considered knee replacement This treatment changed my problem to manageable and I would not have such a good and active life without it.