From the Manufacturer:
Kelp (Fucus Vesiculosus) is one of the best sources of Iodine making it a good treatment for hypothyroidism, obesity, adrenal insufficiencies, energy and endocrine gland disorders.
Kelp (ascophyllum nodosum) is a seaweed with a long history of use as a food and as a source of assailable iodine. Ascophyllum nodosum is a species of Kelp that only grows deep in ocean waters. Off shore Kelps may absorb heavy metals and toxins. Nature's Way kelp, harvested north of the Arctic Circle, is comprised only of valuable nutrients from ocean floors. We use the whole dried Kelp plant.