Fucus vesiculosus is a type of brown seaweed that is harvested from cool waters along the Atlantic Ocean. Bladderwrack is distinguishable by its air-filled “bladders”, or thalli, that keep it afloat. The seaweed has a naturally high iodine content and is enjoyed for its nutritious value. Bladderwrack can be added to soups, stocks, and broths, or it can even be steeped as tea. Bladderwrack is also called dyer’s focus, red focus, and rockwrack. It is a member of the Fucaceae family. This information is for education purposes, and is not intended to diagnose, treat, cure, or prevent any disease. This information has not been evaluated by the Food and Drug Administration.