Bladderwrack is a type of brown seaweed. The name comes from the air pockets in its leaves, which look like small bladders. The air pockets help the seaweed float. Bladderwrack grows in the ocean, ...

Bladderwrack is an edible brown seaweed that has been used as a natural medicine for centuries. It’s available dried, powdered, as a tea, or in supplement form. But it’s effectiveness is questionable.