Green-lipped mussel has been promoted as a dietary supplement for relieving arthritis and joint pain and stiffness and for rebuilding connective tissue, tendons, ligaments, and cartilage because it contains a large amount and diversity of glycosaminoglycans (see the "Chondroitin Sulfate" and "Clucosamine" sections of this chapter). It also contains a high amount of w-3 fatty acids that may help to reduce or prevent inflammation by balancing eicosanoid production.
Although a few studies in animals have shown promise for green-lipped mussel as an anti-inflammatory and for the pain and stiffness of arthritis, there have been few and conflicting studies for its use in humans. If indeed it is a good anti-inflammatory, it may also help to promote postexercise recovery, but there is no direct clinical evidence in athletes to support this. With its theorized mode of action, and the lack of clinical studies to directly support it, it may be wiser to use a more concentrated form with more clinical support of glycosaminoglycans, such as chondroitin and glticosamine sulfate.
Inflammatory Conditions and Asthma
A lipid extract of New Zealand green-lipped mussel was tested in patients with atopic asthma in a double-blind, placebo-controlled, randomized clinical trial. The treatment group received a lipid extract (Lyprinol, 50mg of w-3 fatty acids and olive oil); the placebo group received only 150 mg of olive oil. The treatment group was found to have significantly reduced daytime wheeze and exhaled hydrogen peroxide and an increase in morning peak expiratory flow with no side effects. Since asthma is a chronic inflammatory disease involving the mediation of leukotrienes, it was suggested that Perna ctmalicuJus worked at least partially through the mechanism of inhibiting 5-lipooxygenase and cyclo-oxygenase (which is responsible for production of eicosanoids), as it was found to do in experimental studies (Emelyanov et al., 2002).
Rheumatoid and Osteoarthritis
In a randomized, placebo-controlled clinical study of green-lipped mussel extract for rheumatoid arthritis, 35 patients were given either Seatone (green-lipped mussel extract) or a placebo for 6 months. The treatment group showed no difference in any of the clinical or laboratory outcome measures, and the researchers concluded the extract was not effective for rheumatoid arthritis (Larkin et al., 1985).
Caughey et al. (1983) tested a freeze-dried extract of New Zealand green-lipped mussel for the treatment of rheumatoid arthritis in an early clinical study. Treatment with the green-lipped mussel extract was found to be beneficial for the pain and inflammation associated with arthritis.
Gibson et al. (1980) examined the effect of green-lipped mussel (three 350-mg capsules daily) or matched placebo in a double-blind, randomized, clinical study involving 66 patients with rheumatoid arthritis (28) and osteoarthritis (38). All patients were allowed to continue their previous medication of NSAIDs during the study. The outcome measures studied for rheumatoid arthritis were articular index of joint tenderness, morning stiffness, grip strength, pain (using a visual analog scale), functional index, and a timed walking test. The outcome measures studied for osteoarthritis were degree of morning stiffness, pain (by visual analog scale), functional index, limed walking test, and range of movement in hip and knee joints. Separate physician- and patient-assessed improvement measures were also recorded in all groups. At the end of the trial, green-lipped mussel was concluded to be an effective supplement or possible alternative to regular treatment of both rheumatoid and osteoarthritis.
Green-lipped mussel treatment was able to reduce the amount of pain and stiffness, improve the patients' ability to cope with their conditions, and enhance general health with a low occurrence of side effects.
Dosage recommendations vary widely for green-lipped mussel, from 500 to 3,000 mg/day in divided doses. No serious side effects have been reported, but green-lipped mussel may cause a problem with people prone to shellfish allergy. Additionally, people who have an aversion to the smell of fish may be repelled by this supplement!