What is Fucoidan? Fucoidan is the slurry material found on the exterior surface of seaweed. Because it plays a major role in sustaining critical marine life, it acts as a remarkable protectant, is rich in nutrition, and has remarkable healing properties. Why Mozuku Fucoidan? Mozuku is harvest from the Tongan Republic in the pristine environment of the Southern Pacific Ocean, and through scientific research, has been proven to be the purest and more potent form of seaweed. It contains the highest levels of fucoidan essence. Because of the unique qualities found in this essence, it is often used in Japan and other countries as the main ingredient in the treatment of many degenerative illnesses.