Iodine how much to take

Moreover, the doses used in these studies approximately 1,—6, mcg per day are several times higher than the iodine UL of 1, mcg for adults. Doses of this magnitude should only be used under the guidance of a physician [ 2 ].

Radiation-induced thyroid cancer Nuclear accidents can release radioactive iodine into the environment, increasing the risk of thyroid cancer in exposed individuals, especially children [ 77 , 78 ]. Thyroidal uptake of radioactive iodine is higher in people with iodine deficiency than in people with iodine sufficiency. For this reason, iodine-deficient individuals have a particularly high risk of developing radiation-induced thyroid cancer when exposed to radioactive iodine.

The FDA has approved potassium iodide as a thyroid-blocking agent to reduce the risk of thyroid cancer in radiation emergencies involving the release of radioactive iodine [ 77 ]. The FDA recommends that exposed people take a daily pharmacological dose 16— mg potassium iodide, depending on age until the risk of significant radiation exposure ends [ 77 , 78 ]. Potassium iodide was widely used in Poland following the Chernobyl accident and childhood thyroid cancer rates did not increase substantially in subsequent years [ 79 ].

In areas where iodide prophylaxis was not used, such as Belarus and Ukraine, where many children were mildly iodine-deficient, the incidence of thyroid cancer sharply increased among children and adolescents [ 77 ].

High intakes of iodine can cause some of the same symptoms as iodine deficiency—including goiter, elevated TSH levels, and hypothyroidism—because excess iodine in susceptible individuals inhibits thyroid hormone synthesis and thereby increases TSH stimulation, which can produce goiter [ 2 , 80 ].

Iodine-induced hyperthyroidism can also result from high iodine intakes, including when iodine is administered to treat iodine deficiency. Studies have also shown that excessive iodine intakes cause thyroiditis and thyroid papillary cancer [ 2 , 80 ]. Cases of acute iodine poisoning are rare and are usually caused by doses of many grams. Acute poisoning symptoms include burning of the mouth, throat, and stomach; fever; abdominal pain; nausea; vomiting; diarrhea; weak pulse; and coma [ 2 ].

Responses to excess iodine and the doses required to cause adverse effects vary [ 81 ]. Some people, such as those with autoimmune thyroid disease and iodine deficiency, may experience adverse effects with iodine intakes considered safe for the general population [ 2 , 5 ].

In most people, iodine intakes from foods and supplements are unlikely to exceed the UL [ 2 ]. Long-term intakes above the UL increase the risk of adverse health effects. The ULs do not apply to individuals receiving iodine for medical treatment, but such individuals should be under the care of a physician [ 2 ].

Iodine supplements have the potential to interact with several types of medications. A few examples are provided below. Individuals taking these medications on a regular basis should discuss their iodine intakes with their healthcare providers. Taking high doses of iodine with anti-thyroid medications can have an additive effect [ 81 ] and could cause hypothyroidism. Taking potassium iodide with ACE inhibitors can increase the risk of hyperkalemia elevated blood levels of potassium [ 81 ].

The federal government's — Dietary Guidelines for Americans notes that "Because foods provide an array of nutrients and other components that have benefits for health, nutritional needs should be met primarily through foods.

In some cases, fortified foods and dietary supplements are useful when it is not possible otherwise to meet needs for one or more nutrients e. For more information about building a healthy dietary pattern, refer to the Dietary Guidelines for Americans and the U. Department of Agriculture's MyPlate. This fact sheet by the Office of Dietary Supplements ODS provides information that should not take the place of medical advice.

We encourage you to talk to your healthcare providers doctor, registered dietitian, pharmacist, etc. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice. Updated: March 29, History of changes to this fact sheet. Find ODS on:. Strengthening Knowledge and Understanding of Dietary Supplements. Health Information Health Information.

Iodine Fact Sheet for Health Professionals. Health Implications of Perchlorate Ingestion. Institute of Medicine, Food and Nutrition Board.

World Health Organization. Assessment of iodine deficiency disorders and monitoring their elimination. Geneva, Switzerland: WHO, Patrick L. Iodine: deficiency and therapeutic considerations. Altern Med Rev. Iodine deficiency. Endocr Rev. Iodine-deficiency disorders. Prevention and control of iodine deficiency in pregnant and lactating women and in children less than 2-years-old: conclusions and recommendations of the Technical Consultation.

Public Health Nutr. Pennington JA, Young B. Iron, zinc, copper, manganese, selenium, and iodine in foods from the United States Total Diet Study.

J Food Compost Anal. Development of databases on iodine in foods and dietary supplements. Nutrients ;10; Iodine database PDF. Department of Agriculture, Beltsville MD. July Food and Drug Administration. Roseland J. Personal Communication. August 13, Composition of Core Foods of the U.

Food Supply, Copper, Manganese, Selenium, and Iodine. J Food Comp Anal. Variability of iodine content in common commercially available edible seaweeds. Fortification Legislation. Iodized salt data. Iodine nutrition: iodine content of iodized salt in the United States. Environ Sci Technol. Revised April 1, National Institutes of Health. Dietary Supplement Label Database. Bioavailability of seaweed iodine in human beings. Actions for this page Listen Print. Summary Read the full fact sheet.

On this page. Iodine in food Recommended dietary iodine intake How to get enough iodine in your diet Iodine deficiency Iodine and pregnancy Iodine deficiency in babies and children Excessive amounts of iodine can be harmful Where to get help.

Iodine in food Iodine is found naturally in a range of foods such as: dairy products seafood seaweed kelp eggs some vegetables. Iodine deficiency disorders , , World Health Organization. Zimmermann MB. Salt reduction , , World Health Organization. Monitoring the health impacts of mandatory folic acid and iodine fortification, , Australian Institute of Health and Welfare, Australian Government.

Iodine supplementation for pregnant and breastfeeding women , , National Health and Medical Research Council, Australian Government.

Charlton K, Skeaff S, , Iodine fortification: why, when, what, how, and who? Give feedback about this page. Was this page helpful? Iodine is important before birth and in babies and young children. It is essential for the development of the brain and nervous system, the 5 senses, alertness and coordination. Too little iodine may cause extreme tiredness, feeling cold, problems concentrating and hair loss. And without enough iodine, the thyroid gland may enlarge to form a goitre.

It shows up as a lump in the neck. Too much iodine usually from supplements can be dangerous for people with thyroid disorders. You get iodine from food. Foods high in iodine include seafoods such as oysters, snapper and seaweed. Tinned salmon, bread, eggs, milk and milk products such as yoghurt also contain iodine. Iodised salt is now used in bread making. The packaging will tell you how much iodine the bread contains.

If you are pregnant, check if you are eating enough iodine. Low iodine levels can increase the risk of a miscarriage. It can also lead to stunted growth and intellectual disability or reduced IQ in the baby. The National Health and Medical Research Council recommends that all women who are pregnant, breastfeeding or considering pregnancy take an iodine supplement of micrograms a day to top up their intake as otherwise they are unlikely to get all the iodine they need every day.

Talk to your doctor about this. Women who have a thyroid condition should not take iodine supplements until they have checked with their doctor. If you are pregnant, avoid kelp seaweed supplements as these may contain varying levels of iodine and may contain heavy metals such as mercury. Learn more here about the development and quality assurance of healthdirect content. Tasmanians are now getting the ideal amount of iodine in their diets, thanks to an Australian first initiative.

Some types of plant-based milk are also fortified with iodine. If you are considering taking a supplement seek advice from a healthcare professional. The Vegan Society has more information about iodine and vegan diets.

Taking high doses of iodine for long periods of time could change the way your thyroid gland works.