What are Green Lipped Mussels? This shellfish comes from New Zealand. It differs from other mussel species in that it has a dark brown/green shell and a green lip around the edge of the shells. It is also one of the largest mussel species growing up to 240 mm in length. This product is a food supplement containing green lipped muscle shell powder. What Do Green Lipped Mussels Do? Green Lipped Mussels help to maintain healthy joints. They also contain Omega 3 fatty acids which help to maintain a healthy immune system. Mussels are an excellent source of selenium and vitamin B12 and a good source of zinc and folic acid.