Kelp can be one of several brown-colored seaweed species called Laminar. Kelp is a vegetable found only in the sea that possesses high concentrations of useful minerals including iodine, potassium, magnesium, calcium, and iron. Laminaria as a source of iodine kelp may be useful as a supplement for making thyroid hormones, which are required for maintaining normal metabolism in all cells of the body.

Dosage and Administration

With the introduction of iodized salt, other sources of iodine, such as kelp, have become much less popular. A report from Great Britain indicated that the average kelp-based supplement contained 1,000 mcg of iodine (the adult RDA in the United States is 150 mcg per day). It has been suggested that intakes above 2,000 mcg per day should be regarded as excessive or potentially harmful.