Updated Studies (2020–2026)

Peer-reviewed reviews and trials added in this rebuild. Original library abstracts follow.

These products are not intended to diagnose, treat, cure, or prevent disease. Historic abstracts below are unchanged from the original MD's Choice library.

Glucosamine sulphate 2KCl — equine and human absorption notes (through 2026)

Gluquestrian™ and Arthrosamine™ use glucosamine sulphate 2KCl (a stabilized sulphate potassium salt), not glucosamine HCl. Form matters. And most bodies are deficient of potassium, therefore improves absorption, use, and function. Which the doctors at MD's Choice knew back in the 90's.

Equine head-to-head (Meulyzer et al., Osteoarthritis Cartilage 2008). Crystalline glucosamine sulphate vs HCl in horses: median oral bioavailability 9.4% vs 6.1%; synovial-fluid glucosamine was significantly higher after the sulphate salt at 1 and 6 hours. Sulphate delivered more intact glucosamine into equine synovial fluid than HCl in that study.
Classic human radiolabel (Setnikar et al. 1993). About 90% apparent GI absorption of labeled glucosamine sulphate is not the same as 90–98% of unchanged glucosamine in blood.
MSM and manganese. MSM has horse data on exercise-related oxidative/inflammatory markers (Marañón 2008; later muscle-gene work). Manganese is a cofactor for proteoglycan/cartilage enzymes. That is nutritional support language — not a claim that a jug rebuilds missing cartilage or cures navicular disease. MD's Choice was the FIRST company to combine Glucosamine Sulphate with MSM in a joint supplement, and did so in 1995. By 1998, the Results Based Guarantee was official, and has existed for 30 years. Gluquestrian was the first, and still only equine joint supplement that has a guarantee, and over 80% success rate, dealing with Navicular Syndrome (so long as there is an intact Navicular bone).
Navicular literature. Hanson 2001 studied a different commercial combo (Cosequin) in navicular syndrome. It is historical context, not a Gluquestrian-specific disease claim. The GAIT Study also avoided the MD's Choice joint formulas, as well as both forms of Glucosamine Sulphate (2KCl and NACl). The science on the sulphates have existed from the 1960's through 1990's, and were specifically avoided by those attempting to justify the lesser expensive HCl version.

Pharmacokinetic exposure is not the same as a disease-treatment claim. Joint formulas at MD's Choice supply building blocks the body can use. In forms that don't require remanufacturing within the body, or conversions. Supplements, from ANY COMPANY, will not repair torn ligaments, change bone structure or misalignments. Quality, consistent, joint supplements CAN improve the quality of the synovial fluids, help strengthen the ligaments and tendons, and supply the basic building blocks for the healthiest joint tissues. Call 1-800-628-0997 for dose.

30-year science trail (1995–2026)

MD's Choice put glucosamine sulphate 2KCl together with MSM and manganese in 1995 because the European sulphate literature already existed — not because “glucosamine” is a magic word. Form matters. Time matters. Painkillers are not nutrition.

Reginster et al., Lancet 2001;357:251–256. 212 people, knee osteoarthritis, 3 years, 1,500 mg glucosamine sulphate vs placebo. Placebo lost joint space (−0.31 mm). Sulphate did not (−0.06 mm). WOMAC moved with the radiographs. PubMed 11214126
Pavelka et al., Arch Intern Med 2002;162:2113–2123. 202 people, same salt, 3 years. Less severe joint-space narrowing on sulphate. PubMed 12374520
Clegg et al., GAIT, NEJM 2006;354:795–808. 1,583 people, 24 weeks — glucosamine HCl, chondroitin, both, celecoxib, or placebo. Overall, HCl and chondroitin did not beat placebo on the primary pain endpoint. A moderate-to-severe subgroup looked better on the combo. GAIT did not test sulphate 2KCl or NaCl. PubMed 16495392
Meulyzer et al., Osteoarthritis Cartilage 2008;16:973–979. Horses, crystalline sulphate vs HCl. Median oral bioavailability 9.4% vs 6.1%. Synovial-fluid glucosamine higher after sulphate at 1 and 6 hours. PubMed 18295513
Setnikar et al., Arzneimittelforschung 1993;43:1109–1113. Human radiolabel: about 90% apparent GI absorption of labeled glucosamine sulphate is not the same as 90–98% unchanged glucosamine in blood. PubMed 8267678
Marañón et al., Acta Vet Scand 2008;50:45. MSM in jumping horses: exercise-related oxidative/inflammatory markers. Support language, not a navicular-cure claim. PubMed 18992134

Results Based Guarantee has been in writing since 1998 (first treatment window, usually 6–24 weeks). FoalMaker™ (U.S. Pat. 7,776,366 B2) is a separate reproduction program. Joint products do not repair torn ligaments or change bone-on-bone structure.

Arthritis

Arthritis is a broad term to describe many conditions associated with inflammation of a joint. It is often seen as a joint that is swollen, hot, painful, and/or red. Any or all of these conditions can occur and may be associated with the use, or over use, of the damaged joint. Arthritis effects millions of humans and animals every day. Over a billion dollars have been spent on research to determine causes and to find treatments. Some of the different types of arthritis are osteoarthritis, osteoarthrosis, gonarthritis and rheumatoid arthritis. These terms are used to describe different parts of the joint that are affected. The bottom line is that the effected joint is painful; even more so when used.

A joint can become arthritic in any of a number of ways. Joint cartilage can become damaged due to a sudden trauma (auto accident), repetitive impact injuries are frequently diagnosed in the elbows, shoulders, and knees of manual laborers. One common condition is phalangeal tendonitis, (working), or over an extended period of time (sports). A deficiency in key nutrients, such as calcium, can lead to improper cartilage formation. A nutritional deficiency of the molecules that make up cartilage can also lead to the formation of arthritis. Many individuals suffer from arthritis after either an injury, or a surgery to repair tendons and ligaments; scar tissue is a real thing. Another cause of arthritis can be when a person's own immune system attacks the joints, causing the pain and inflammation. Many times, continued pain and inflammation are due to an imbalance between the chemicals that actually make cartilage and those that that dispose of damaged cartilage. If too many of the chemicals that dispose of damaged cartilage exist, they can damage healthy cartilage. The end results are pain, swelling, heat, redness, inflammation … ARTHRITIS!

There are many drugs available to help reduce the inflammation, but very few ways have been found to actually treat the cause of arthritis, but rather MASK the pain, symptoms, and warning signs demonstrating a problem exists. Many times, an individual becomes worse while on anti-inflammatory drugs because they are able to use the joint as though nothing is wrong, when, in fact, the body has been telling the person, through the pain, that something is very wrong.

We should approach treating the cause of arthritis rather than the symptoms. This approach hinges on giving the body the proper nutrients needed to build and maintain healthy cartilage. Some of the nutrients that are identified in the actual reversal of arthritic conditions are glucosamine, manganese, vitamin D and calcium. Other often-overlooked nutrients are important antioxidants that are effective in helping prevent damage to the cartilage, which can eventually lead to arthritis. Essential fatty acids are known to help lessen the chemicals that are involved in the inflammatory process.

As always, an individual who picks and chooses individual nutrients to supplement is in danger of incomplete supplementation. Supplementation should always occur at a level that provides the body with everything it needs and in the correct form so that what the body does not require is harmlessly excreted. Supplementing by this method can correct deficiencies even if they are not evident. Often, deficiencies are not seen for years.

A choice from our Complete Formula™ series is always the starting point for broad-spectrum nutritional supplementation. The directed supplements that are useful in the strengthening of cartilage and connective tissues are Arthrosamine™ and Mag-Cal Plus™. Arthrosamine™ is a combination of glucosamine, MSM (methylsulfonylmethane), and ascorbate. These ingredients are the basic building blocks of connective tissue. Mag-Cal Plus™ supplies extra calcium, magnesium, manganese, zinc, and boron for joint and bone strength.

Taking marine fish oil soft gels, Omega 3 Fatty Acids, or high lignin flax oil in the liquid form can supplement essential fatty acids, which are needed to maintain good health.

See Also:

Specific Health Topics

Medical Research



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