Edible seaweed is one of nature's free superfoods, comprising various types of multicellular algae which form complete proteins, having all nine amino acids required for human nutrition. Historically from the Far East, seaweed consumption is now widespread.
Many different types of seaweed can be eaten, from the purplish-black nori used to wrap the rice served in sushi, to green leafy varieties that are processed into sheets. Kombu, a group of long brown varieties, can either be served as a vegetable, dried, or boiled in soups and stews. Shredded or powdered kombu is also used as an additive or can be made into tea. One leathery red seaweed can be chewed raw, added to cooked dishes or dried as a salty health snack.
Protein content varies over species, from 10% up to 50%, with nori being one of the most nutritious. Most varieties have significant quantities of vitamins C, A, K and members of the B complex, and many minerals including calcium, magnesium, iron, iodine, copper, zinc and manganese.
Seaweeds contain relatively high amounts of fibre in the form of polysaccharides, which contribute to reducing blood cholesterol levels, regulating blood sugar and fat levels and promoting good cardiovascular health.