En Español (Spanish Version) Fucus vesiculosus
Black Tang;Cut Weed;Rockweed;Rockwrack;Seawrack
Principal Proposed Uses
Other Proposed Uses
Bladderwrack is a type of seaweed found on the coasts of the North Sea, the western Baltic Sea, and the Atlantic and Pacific Oceans. A common food in Japan, it is used as an additive and flavoring in various food products in Europe. Bladderwrack is commonly found as a component of kelp tablets or powders used as nutritional supplements. It is sometimes loosely called kelp, but that term technically refers to a different seaweed.
Bladderwrack contains high concentrations of iodine, and for this reason it has been recommended as a treatment for hypothyroidism(underactive thyroid gland).1 However, iodine will only help for the type of hypothyroidism caused by iodine deficiency, which is a relatively rare condition in the developed world. If your iodine levels are not low, taking extra amounts of iodine can cause your thyroid gland to become either over- or underactive, causinghyperthyroidism or hypothyroidism, respectively. Furthermore, the amount of iodine supplied by bladderwrack is unpredictable.
A component of bladderwrack called alginic acid swells upon contact with water. When taken orally, it forms a type of seal at the top of the stomach, and for this reason is used in over-the-counter preparations for heartburn. The same constituent gives bladderwrack laxative properties, as well.2
Last reviewedSeptember 2014by EBSCO CAM Review Board
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