The use of glucosamine for joint support and the treatment of joint related conditions such as osteoarthritis and rheumatoid arthritis is well established.  There appears to be some confusion, however, and a general lack of information as to the whether the use of glucosamine sulphate is better and more efficient over that of glucosamine hydrochloride and vice versa.

The delivery vehicle: hydrochloride or sulphate

What should be remembered is that the active ingredient in any glucosamine product is only the glucosamine element, and that the hydrochloride or sulphate acid salt is purely a delivery vehicle.  Therefore, the amount of glucosamine present in 1500 mg of glucosamine salt will depend on the amount of ‘vehicle’ present and whether additional salts are included by the manufacturer.  In short, the benefits delivered by a product will depend on its purity and stability, and this is where the two salts differ.

The simple answer is that they both fare equally in their actions; the majority of early trials and studies have primarily used glucosamine in its sulphate form, over hydrochloride, purely because of availability at the time.  Not surprisingly, much of the data has rested on the actions of glucosamine sulphate.  Only more recently has glucosamine hydrochloride been able to stand its ground and the results from several well conducted trials demonstrate that hydrochloride is as efficient as the sulphate form (Houpt et al, 1999; Qiu et al, 2005; Zang et al, 2007)

Purity & stability

The hydrochloride form of glucosamine is more concentrated than sulphate, and the hydrochloride form contains substantially less sodium per effective dose. Glucosamine sulphate is stabilised with sodium chloride – more commonly known as table salt – and can contain as much as 30% sodium. Given that we are advised to reduce our salt intake, this is a consideration for individuals who want or need to reduce their dietary intake of sodium.

The content of other salts will also affect the dosage needed to achieve the relevant amount of glucosamine.  For example, given that the upper limit of glucosamine is set at 1.5 g per day, you would need to consume around 2g of glucosamine sulphate to equal the benefits of 1.5g of glucosamine hydrochloride. This is because glucosamine hydrochloride is naturally stable and requires no added salt or other preservatives.  Simply put, glucosamine hydrochloride provides the same benefits as that of glucosamine sulphate but because of stability and purity it is actually more efficient and better value in the sense that it delivers the actual amount of glucosamine as stated on the product label.

References

Houpt JB, McMillan R, Wein C, Paget-Dellio SD.  Effect of glucosamine hydrochloride in the treatment of pain of osteoarthritis of the knee. J Rheumatol. 1999 26:2423-30.

Qiu GX, Weng XS, Zhang K, Zhou YX, Lou SQ, Wang YP, Li W, Zhang H, Liu Y. A multi-central, randomized, controlled clinical trial of glucosamine hydrochloride/sulfate in the treatment of knee osteoarthritis Zhonghua Yi Xue Za Zhi. 2005 85:3067-70. Chinese.

Zhang WB, Zhuang CY, Li JM, Yang ZP, Chen XL. Efficacy and safety evaluation of glucosamine hydrochloride in the treatment of osteoarthritis  Zhonghua Wai Ke Za Zhi. 2007 45:998-1001.