Recent headlines are bringing awareness to an iodine mineral deficiency growing in many parts of the world. In this post, we look at the mineral iodine.
Top Takeaways:
- Iodine is essential for thyroid health, metabolism, brain development, and immune support.
- Natural iodine sources like seaweed and fish are beneficial, but fortified foods like iodized salt and dairy are typically necessary.
- Incorporating iodized salt into cooking is a simple, affordable, and effective way to prevent iodine deficiency.
What is iodine?
Iodine is an essential trace mineral our bodies require to produce thyroid hormones, which are key in regulating bodily functions.
Since our bodies do not make iodine, we must get this mineral from our diet.
Why do we need iodine?
Our bodies require iodine to produce two key hormones: thyroxine (T4) and triiodothyronine (T2). Without these hormones, our health is adversely impacted.
Iodine influences our:
- Thyroid health
- Brain development
- Metabolism regulation
- Immune system support
If we are deficient in iodine, we can experience adverse health effects, including goiters, hypothyroidism, hyperthyroidism, developmental delays in children, pregnancy complications, thyroid cancers, and more.
Why is iodine added to salt and other foods?
Iodine is naturally occurring but not equally distributed in our environment. So, many parts of the world do not have iodine available in the soil or water; therefore, it’s not available in the foods people consume in their diet.
In the early 1900s, the United States experienced a “goiter belt,” a cluster of states primarily in the Great Lakes, Appalachians, and Northwestern regions with high levels of iodine deficiency diseases.
In response to this concern, a coalition of Michigan doctors advocated to fortify salt with iodine. This proactive measure successfully reduced the incidence of iodine deficiency diseases.
Who needs the most iodine? How much iodine do I need?
While all people need proper iodine levels to maintain their health, infants, children, pregnant people, and nursing people are more at risk for experiencing the adverse effects of iodine deficiency.
The amount of iodine a person needs varies, but generally, the amounts below are what we require to maintain our health.
- Adults: 150 micrograms per day
- Pregnant people: 220 micrograms per day
- Breastfeeding people: 290 micrograms per day
- Children: Between 90-120 micrograms per day, depending on age
Unless you take iodine supplements, consuming excessive amounts of iodine is rare. For adults, iodine intake becomes excessive when it exceeds 1,100 micrograms per day.
Where do I find iodine naturally?
We find iodine in foods grown or produced in iodine-rich environments.
Naturally-rich iodine foods include:
- Seaweed: Kelp, nori, wakame, and more
- Fish and Shellfish: Cod, tuna, shrimp, scallops and more.
While produce grown in iodine-rich soil does contain iodine, the levels are often insufficient to meet daily health requirements, so we need to include additional iodine sources in our diet.
Is consuming naturally iodine-rich foods sufficient, or should I also include iodine-fortified foods in my diet?
Most people do not meet their iodine needs from foods naturally-rich in iodine. We can meet our nutritional needs by consuming foods fortified with iodine.
Iodine-enriched foods include:
- Ionized salt
- Dairy products (e.g., milk, cheese, yogurt)
- Eggs
Should I use ionized salt?
Most people benefit from using and cooking with ionized salt, as it is a simple and affordable way to meet nutritional needs.
Why are iodine deficiency levels increasing?
There are many reasons for increased iodine deficiency. The literature more commonly discusses two reasons: people switching from fortified salts to salts without added iodine (e.g., pink Himalayan salt) and people consuming more processed foods that include salt/sodium but do not contain iodine.
What should I do if I think I am deficient in iodine or another nutrient?
Reach out to your primary care physician or another state-licensed medical professional if you are concerned about your health. They will be able to create a plan for your specific health needs.
The good news.
Addressing iodine deficiency can be as simple as incorporating iodized salt into your cooking. This proven solution is both safe and effective when used as part of a healthy, balanced diet.
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Learn more: citations and further readings.
Trending – Sodium & Salt: https://cris.msu.edu/news/trending/trending-sodium-salt/
Pearce, E. N., Lazarus, J. H., Moreno-Reyes, R., & Zimmermann, M. B. (2016). Consequences of iodine deficiency and excess in pregnant women: An overview of current knowns and unknowns. The American Journal of Clinical Nutrition, 104(Suppl_3), 918S–923S. https://doi.org/10.3945/ajcn.115.110429
Rohner, F., Zimmermann, M., Jooste, P., Pandav, C.,Caldwell, K., Raghavan, R., & Raiten, D. J. (2014). Biomarkers of nutrition for development—iodine review. The Journal of Nutrition, 144(8),1322S–1342S. https://doi.org/10.3945/jn.113.181974
World Health Organization (WHO). (2024, June 28). People in the WHO European Region at greater risk of iodine deficiency due to changing diets. Retrieved from https://www.who.int/europe/news-room/28-06-2024-people-in-the-who-european-region-at-greater-risk-of-iodine-deficiency-due-to-changing-diets
Worth its salt. (2024, Nov 09). The Economist, 453,76. Retrieved from https://www.economist.com/science-and-technology/2024/11/06/as-wellness-trends-take-off-iodine-deficiency-makes-a-quiet-comeback.
Zimmermann, M. B. (2009). Iodine deficiency. Endocrine Reviews, 30(4), 376–408. https://doi.org/10.1210/er.2009-0011