Gold Member Badge


  • You're all caught up!

Toxicity of Iodine

author image Owen Pearson
Owen Pearson is a freelance writer who began writing professionally in 2001, focusing on nutritional and health topics. After selling abstract art online for five years, Pearson published a nonfiction book detailing the process of building a successful online art business. Pearson obtained a bachelor's degree in art from the University of Rio Grande in 1997.
Toxicity of Iodine
A plate of seaweed salad on a bamboo mat. Photo Credit: Amawasri/iStock/Getty Images

Iodine is a trace mineral that is naturally found in the human body and is also derived from food sources such as dairy products, kelp, haddock, cod, perch and sea bass. In the United States, table salt is typically fortified with iodine. Multivitamins and potassium iodide supplements also serve as sources of this mineral. In rare cases, overconsumption of iodine can lead to toxicity.

Video of the Day

Tolerable Upper Limit

The recommended daily intake of iodine for adults is 150 micrograms, according to the Linus Pauling Institute at Oregon State University. However, the tolerable upper limit, which represents the maximum safe dosage, is 1,100 micrograms for adults. Most people, except for those in areas such as Northern Japan known for heavy seaweed consumption, consume less than 1,000 micrograms of iodine per day.

Moderate Toxicity

Moderate toxicity is typically marked by elevated levels of thyroid stimulating hormone, or TSH, in the bloodstream. Moderate toxicity, which can occur at levels above the tolerable upper limit, may result in hypothyroidism, or insufficient production of thyroid hormones that regulate metabolism of food nutrients. Consumption of more than 1,700 micrograms of iodine per day may cause goiter, or enlargement of the thyroid gland, according to the Linus Pauling Institute.

Acute Toxicity

Acute toxicity typically occurs at dosages of more than 1 gram of iodine, according to the Linus Pauling Institute. Acute iodine toxicity may cause symptoms such as diarrhea, nausea and vomiting, as well as a burning sensation in the stomach, throat and mouth. Weak pulse and coma are also potential complications of acute toxicity.


Although heavy consumption of iodine may cause toxic symptoms, this mineral serves important functions in the human body when taken in recommended doses. Iodine aids in the metabolism of nutrients for energy, according to the University of Maryland Medical Center. It also supports proper thyroid function and may help prevent cretinism, a type of mental and physical retardation.

LiveStrong Calorie Tracker
Lose Weight. Feel Great! Change your life with MyPlate by LIVESTRONG.COM
  • Gain 2 pounds per week
  • Gain 1.5 pounds per week
  • Gain 1 pound per week
  • Gain 0.5 pound per week
  • Maintain my current weight
  • Lose 0.5 pound per week
  • Lose 1 pound per week
  • Lose 1.5 pounds per week
  • Lose 2 pounds per week
  • Female
  • Male
ft. in.


Demand Media