What is it?

Green-lipped mussel (Perna canaliculus) is a New Zealand shellfish, from which an extract has been shown to be useful in the treatment of rheumatoid arthritis (RA) and osteoarthritis (OA).

Green-lipped mussel inhibits inflammation in the body. Although inflammation is normal under certain conditions, consistent or excessive inflammation can result in pain and damage to the body, including the joints. The human body makes several chemical mediators of inflammation. Levels of these chemicals in the body may be higher in people with RA who are experiencing symptoms than in symptom-free people with arthritis.¹ Evidence indicates that controlling the production of inflammatory mediators in the body may help improve conditions such as arthritis, asthma, psoriasis, and inflammatory bowel disease (including ulcerative colitis and Crohn’s disease), all of which involve elements of inflammation.²

Research on green-lipped mussel has focused primarily on OA and RA. Although some studies have failed to demonstrate therapeutic benefit of green-lipped mussel in people with arthritis,^{3 4} the outcomes of other studies have been more positive.^{5 6 7} In one trial, both freeze-dried powder and lipid extract of green-lipped mussel were effective at reducing symptoms in 70% of people with OA and 76% of people with RA.⁸ A similar study of people with either OA or RA showed green-lipped mussel reduced pain in 50% and 67% of the patients, respectively, after three months of supplementation.⁹

In 1986, dried mussel extracts became available that were stabilised with a preservative. The earlier studies that found no beneficial effect of green-lipped mussel on arthritis all used preparations that had not been stabilised, a point that may help explain some of the discrepancies in the research. One recent animal study compared the two forms and found a stabilised lipid extract to be significantly more effective than a nonstabilized extract at inhibiting inflammation.¹⁰ Because both forms are currently available on the market, it may be prudent to check on the form.

Nonsteriodal anti-inflammatories (NSAIDs), such as aspirin and ibuprofen, are often used for inflammatory conditions. However, most of these medications can produce the unfortunate side effect of stomach irritation, which may lead to stomach ulcer if taken frequently. One animal study found that green-lipped mussel significantly reduced stomach ulcers resulting from taking NSAIDs.¹¹

In a double-blind study of people with asthma, supplementation with a proprietary extract of New Zealand green-lipped mussel (Lyprinol®) twice a day for 8 weeks significantly decreased daytime wheezing and improved airflow through the bronchi.¹² Each capsule of Lyprinol® contains 50 mg of omega-3 fatty acids.