Scientific Name: Ascophyllum nodosum
Origin: United States (Atlantic Ocean)
Kelp is a type of seaweed, specifically long-frond brown algae, which grows to lengths of 200 feet off Japan, Europe, and North America.
Ancient seafarers were well acquainted with the kelp beds off England and France. Early fisherman burned the plant for fuel and wrapped, baked, and ate fish in it. Unlike the Japanese, who eat a great deal of seaweed, Europeans never developed much taste for kelp.
For several decades, Europeans and North Americans harvested kelp for its iodine. The fronds were cut off exposed rocks at low tide, hence one popular name cut weed. Eventually other iodine sources replaced kelp, and the harvesting ceased.
Kelp is definitely high in iodine. Back in the days before iodized salt, when iodine deficiency was a real problem, kelp was a real blessing. But today, iodine deficiency is virtually unheard of in developed countries. To function normally, the body needs only a minute amount of iodine (150 micrograms a day) - an amount more than supplied by iodized salt. Additional iodine has no significant effect-until you consume enough to cause iodism, which is almost impossible just from eating kelp
Kelp grows in the cold water off the Atlantic and Pacific coasts of North America. It has a strong, foul odor when fresh, but baking deodorizes it. Authorities discourage using kelp collected close to shore because it may be contaminated by industrial pollutants. If you use kelp, buy it from commercial sources.