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What is kelp? Why is it used for?
Kelp is a type of seaweed found in coastal regions where
the water is shallow enough for light to penetrate to the
sea floor. It is the largest type of seaweed in the world,
with some varieties growing to 30 meters or more in length.
Kelp beds usually grow in forests which are highly productive
ecological systems similar to tropical rain forests. Like
rain forests, they form canopies under which many other species
live, including fish, snails, shrimps and sponges.
Although kelp has no medicinal properties, it is an important
source of food for fish and other marine animals. For humans,
it is a vital source of several minerals, including iodine
(a vital ingredient involved in the creation of thyroid hormones),
magnesium, calcium and iron.
How much kelp should I take?
While there is no recommended daily allowance for kelp, many
practitioners in the U.S. suggest a maximum of 150 micrograms
per day. Because of its high iodine content, however, daily
kelp intake should be monitored closely.
What forms of kelp are available?
Although it can be eaten raw, many specialty stores and Asian
markets prefer to sell dried kelp leaves, either individually
or in bulk. Kelp is also available in capsule or tincture
form. Trace elements of it are also found in many multivitamin
What can happen if I take too much
kelp? Are there any interactions I should be aware
of? What precautions should I take?
Several case studies have suggested that high kelp intake
could provide too much iodine, thus interfering with the normal
function of the thyroid gland. Patients with hyperthyroidism,
or who are taking medication to combat hyperthyroidism, should
avoid all supplements that contain kelp.
Other Resources :
More You Know About Minerals
More You Know About Nutrition
de Smet PA, Stricker BH, Wilderink
F, Wiersinga WM. Hyperthyroidism during treatment with kelp
tablets. Ned Tijdschr Geneeskd 1990;134:10589
Transient hyperthyroidism in a patient taking dietary supplements
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Kim JY, Kim KR. Dietary
iodine intake and urinary iodine excretion in patients with
thyroid diseases. Yonsei Med J Feb 2000;41(1):22-8.
Kupper FC, Kloareg B, Guern J, Potin P. Oligoguluronates
elicit an oxidative burst in the brown algal kelp laminaria
digitata. Plant Physiol Jan 2001;125(1):278-291.
van Netten C, Hoption Cann SA, Morley DR, van
Netten JP. Elemental and radioactive analysis of commercially
available seaweed. Sci Total Environ Jun 2000;8:255(1-3):169-75.