Sea vegetables have been harvested and eaten for centuries in Asian countries, especially Japan, China, and Korea, as well as in coastal regions elsewhere, including the British Isles, the Pacific Islands, and New Zealand. Because Japan leads the world in production, consumption, and exportation of sea vegetables, many varieties of seaweed are best known by their Japanese names, such as arame, kombu, and wakame. As their name implies, sea vegetables are plants that grow in or near the sea. Of the thousands of species of sea vegetables, only a small fraction are used for human consumption. Because they contain high concentrations of many important nutrients, sea vegetables have been referred to as “nature’s medicine chest.”

Sea vegetables are generally sold in their dehydrated form, and if they are stored in an airtight container in a cool dark place, such as a kitchen cupboard, they will keep indefinitely. Because they are dry when purchased, sea vegetables require soaking in water prior to use. Two exceptions are nori sheets and dulse, both of which can be eaten right out of the package. The soaking time varies with the different varieties of sea vegetables, and some expand more than others when soaked. For best results, follow the instructions given on the individual package or in a particular recipe.