Spirulina is among the world’s most popular health supplements, which has been in the US since the late 1970s. In ancient times, Mexicans and Africans consumed Spirulina and it recently gained traction when scientists in NASA proposed that it could be grown in space for use by astronauts.

Composition of Spirulina

Spirulina is a blue-green natural alga widely available in health-food stores as a dietary supplement. It contains antioxidants and other nutrients in abundance that benefit your body and brain. A single tablespoon of dried Spirulina powder contains the following

  • Protein
  • Vitamin B1
  • Vitamin B2
  • Vitamin B3
  • Iron
  • Copper
  • Potassium
  • Magnesium
  • Calcium
  • Zinc 

Does Spirulina contain Iodine?

Yes, in addition to the above-mentioned constituents, Spirulina also contains varying levels of iodine. Iodine is a trace element that is naturally present in certain foods, especially rich in foods that come from the ocean. According to   Linus Pauling Institute, the content of iodine in algae varies widely and can go up to more than 4,500 micrograms.

Role of Iodine From Spirulina

Iodine plays an essential role in thyroid function in the human body. Additionally, iodine has a vital role to play in the well-being of our skeleton and central nervous system. It is recommended that one should have 150 micrograms of Iodine per day for adults. A typical American diet supplies enough iodine, and an excess of it can have an adverse effect on the function of thyroid glands. Although the daily requirement of iodine for a human body is 150 micrograms, the amount which we can get from Spirulina might vary.  It is true that iodine and iron are the most abundant nutrients present in Spirulina, it also contains small amounts of other minerals and vitamins. The amount of iodine varies significantly and it depends completely on the salt content in the water that is being used for Spirulina cultivation.

Spirulina and Thyroid

Some manufacturers market Spirulina for thyroid support due to its iodine content. The iodine present in Spirulina is used by the thyroid gland to produce thyroid hormones to support a healthy metabolism. If you are considering taking Spirulina specifically to benefit from its iodine content, there are few safety concerns you should consider

Excess of Spirulina Can be Harmful

A serving of Spirulina is said to contain 16 micrograms, or about 10% of your daily need, up to over 15,000 micrograms. Too much intake of iodine can cause Goiter and thyroid deficiencies, but an overdose is a rare scenario. The upper limit for iodine consumption is 1,100 milligrams per day for human beings. The excess of iodine has been found to be the root cause of thyroid cancer and hyperthyroidism.

Caution While Using Spirulina

Spirulina is available in powder, pill, flake, or tablet forms. A typical recommended dose of Spirulina is about 500mg. But you should only use the product after consulting your doctor. Inform your doctor about any medications or supplements you might be taking because certain ones might interact with Spirulina. You should only prefer using reputable brands of Spirulina. Some Spirulina can be contaminated with compounds that are toxic to your body. If you have phenylketonuria or autoimmune disease, you are seriously advised not to use Spirulina. Moreover, if you are pregnant or breastfeeding, consult your doctor before using Spirulina.


Note: Please use this as information only. This is not medical advice and you must consult your medical practitioner before taking Spirulina for health-related issues.

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