“Seaweed” -- such a humble name for an extraordinary resource. Factually, seaweeds are macroscopic, multi-cellular, benthic marine algae. Perhaps “herbs of the ocean” would be a more meaningful description.
Seaweeds are best known as the richest natural source of iodine. Although iodine deficiency alone impairs thyroid function, deficiencies of other nutrients found in seaweeds, such as zinc, selenium, and manganese, can exacerbate the effects of iodine deficiency and impede healthy thyroid function.
The highest iodine content is found in brown algae, with dried kelp ranging from 1500-8000 parts per million (ppm) and dried rockweed (Fucus) from 500-1000 ppm. Red and green algae generally have much lower iodine levels.
Like all good things, iodine supplementation can be overdone, particularly with a true kelp such as Laminaria. Excessive levels can cause goiter, limb deformities, even death in foals. Foals from mares supplemented with high levels of iodine are most sensitive to excess iodine levels because iodine is concentrated across the placenta and in the mare’s milk. Mares receiving 48-55 mg iodine per day have had a small percentage of foals born with goiter. The lowest level of dietary iodine reported to cause goiter in a mature horse is 83 mg per day. Research has established that 12-14 mg of iodine per day is safe even for pregnant mares and their foals.
If you are using any of the seaweeds as an iodine source for your horse, it is critically important to know what level o f iodine they provide.
Teeming with trace minerals, antioxidants, vitamins and phytochemicals, ounce for ounce the seaweeds are more broad-spectrum nutrient dense than any other food.
Many people think kelp and seaweed are the same thing; they are not. Of 164 botanical families of seaweeds only four are true kelps. If all you want is iodine, then kelp, fed at SAFE levels is ok, BUT the very high iodine levels mean that you must use LESS of the seaweeds to avoid problems, and this means LESS of all the other wonderful things in seaweed. The true kelps (e.g., Laminaria, Macrocystis) tend to grow very rapidly and are not as “nutrient dense” as most of the cold water seaweeds.
Seaweeds grow at different depths in the ocean, affecting the method of harvest. The Intertidal (between high and low tide) seaweeds can be collected by hand, with rakes or knives, or by various machines. The sublittoral (deeper than the low tide mark) seaweeds are collected with long cutting rakes or by divers. It is a challenge to dry this rich natural material to a moisture level low enough to be stable, with minimal damage to the nutrient content. Although “sun-dried” sounds greener, it often results in a poorer quality end product. Carefully controlled mechanical dehydration can result in consistent quality. Use your eyes and nose. Brown seaweeds should have a brownish, olive green color with a distinctive natural ocean aroma and no chemical or burned overtones.
The powerful nutrients in seaweeds affect nearly all physiological systems. High quality seaweed products support thyroid function and provide many other benefits. . .naturally.
Susan Domizi is Founder and President of SOURCE, INC., which has been harvesting, processing and testing seaweeds for more than 30 years. A technical review, “Iodine in the Horse, Too Much or Too Little?” is available at http://4source.com/technical/iodine1.shtml or request a reprint from SOURCE, INC. www.4source.com or 800-232-2365