Iodine Supplements: Is Lugol’s the Best Option?

When it comes to iodine supplements, Lugol’s Iodine is a supplement many health professionals are familiar with.

But is it actually the best iodine supplement?  
("Best" as in the most effective, safest, and highest quality?)

It’s Kate Mahoney, your food-first supplement expert and founder of the Supplement Academy, here with a [very summarized] Scoop on the quality and bioavailability of iodine supplements. Because with so many iodine products on the market, knowing how to identify an optimally effective and safe iodine supplement can make all the difference in the health of our clients that are in need of supplemental iodine.

In this Supplement Scoop, I’ll summarize:  

Like always, any supplement links I share are clean links [aka affiliate-free] to ensure I continue to provide you with comprehensive, unbiased and agenda-free supplement information, as is in alignment with my integrity. 💜

Now let's dive in! 😀

Over in the SA Community online group (which all Supplement Academy participants get lifetime access to 😍), someone asked the following fantastic question:

 “What are your thoughts on potassium iodide vs Lugol’s Iodine that combines potassium iodide and iodine? Lugol’s only comes in much larger doses (2.5mg being the smallest) vs potassium iodide versions.”  

Though a bit of a layered response, I will do my best to summarize cohesively.

Potassium iodide is known to have very low bioavailability. That said, my understanding is it does and can serve a very specific purposes.  

For example, if nuclear fallout is imminent, high doses of potassium iodide prior to and during high radiation exposure are recommended to help protect the thyroid from radioactive halides.  

But, the iodine itself in potassium iodide isn't very bioavailable.  

As in, it is known to "fill" the thyroid receptors, but is difficult for the body to break down so it can actually utilize the iodine as a nutritional cofactor.  

Therefore, any supplement that contains high amounts of potassium iodide serves a specific purpose due to the lack of iodine bioavailability. 

Time to address the popular iodine supplement, Lugol’s Iodine!

Here's a research article I'm familiar with about Lugol's that you may be aware of, too, to refresh your memory or learn more about Lugol’s history and uses. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5693970/  

Lugol’s Iodine says it contains potassium iodide and iodine. But, as Supplement Academy participants learn in the SQS certification course “Minerals” lesson, for a mineral to be stable, it needs to be chelated to another substance.  

This means any mineral that isn't chelated to another substance is unstable, such as the elemental iodine in Lugol's that—according to Lugol’s supplement label--is separate of and in addition to the potassium iodide.  

As a supplement expert, I question the stability of any unchelated mineral in a supplement or product, such as the elemental iodine in Lugol’s Iodine. 

It causes my critical thinking to question... 🤔
"Is the elemental iodine actually creating some kind of molecular bond with the hydrogen or oxygen in the distilled water to stabilize itself (which would create an inorganic mineral form that isn't bioavailable)?"  

Health professionals who specialize in biochemistry would be more familiar with how the elemental iodine in Lugol's can remain stable. If that's you, thank you in advance for reaching out to give me the lowdown because I would love to learn more!  

If you're curious which iodine supplement I might recommend, it's that time. 😍

There is an iodine product I used exclusively for over a decade before the damndemic. Sadly, like so many other products that have been my staples, the supplement has changed in the past few years, and there hasn't been an opportunity for me to re-verify the quality since the supplement changed.  

The iodine supplement I used to rely on  for over a decade was
BRAND Heritage Store
PRODUCT Atomidine
https://heritagestore.com/products/atomidine 

The product used to be 600 mcg of iodine trichloride [ionized iodine, VERY bioavailable] per drop in a carrier of distilled water.  

When I looked it up thanks to my SA participant’s great question about the popular Iodine supplement, Lugol’s Iodine, I found out herbal extracts have been added to my former favorite iodine supplement [according to the website, added to improve/enhance the bioavailability of the iodine].  

Because of the addition of the herbal extracts, the amount of iodine per drop is now less than it used to be; 450 mcg vs the original 600 mcg.  

That said, this is still one of the highest potencies of bioavailable iodine I am aware of.  

However, the product changes require quality verification.

(Yes, this iodine supplement is vegan.)

In my sleuthing, I also found out that the Heritage Store brand started making a different iodine supplement drops; a food-derived iodine supplement derived from Atlantic Kelp.
https://heritagestore.com/products/nascent-colloidal-iodine 

It appears to be an iodine supplement with good potential due to the high bioavailability of the iodine being derived from kelp. However, the quality would need to be verified to ensure it meets your quality standards and the needs of your clients (as SA participants learn how to do with 100% accuracy by completing the SQS aka Supplement Quality Specialist certification curriculum).  

If I were to inquire about this iodine supplement from kelp, I would ask for documentation that verifies the cleanliness of the Atlantic Kelp and the raw material used to make the vegetable glycerin. Though, I honestly love the fact that this iodine drops supplement is food-derived, which—as Supplement Academy participants learn in the SQS course—is one of the most bioavailable nutrient forms. 😀  

(And yes, this iodine supplement is vegan, too!)

That concludes this Supplement Scoop!

I sincerely hope this information is helpful, colleague. 💜  

Until next time, remember that critical thinking + discernment is a SUPERPOWER. 🌟

Warm regards,
Kate 💜 

Centers for Disease Control and Prevention. “Potassium Iodide (KI) | Radiation Emergencies,” Centers for Disease Control and Prevention, 2025, https://www.cdc.gov/radiation-emergencies/treatment/potassium-iodide.html

João Pedro da Silva Lopes, et al. “Clinical and Forensic Aspects of Potassium Iodide,” PubMed Central, 2024, https://pubmed.ncbi.nlm.nih.gov/38989660/

U.S. Nuclear Regulatory Commission. “Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies,” U.S. Nuclear Regulatory Commission, December 2012, https://www.nrc.gov/docs/ML1209/ML12090A873.pdf  

Manouchehr Saljoughian. “Potassium Iodide: An Antidote for Radiation Exposure,” U.S. Pharmacist, March 17, 2011, https://www.uspharmacist.com/article/potassium-iodide-an-antidote-for-radiation-exposure  

Viroj Wiwanitkit. “Nuclear Detonation, Thyroid Cancer, and Potassium Iodide Prophylaxis,” PubMed Central, 2024, https://pmc.ncbi.nlm.nih.gov/articles/PMC3125013/   A. J. Salle, A. S. Lazarus. “Resistance of Bacteria and Embryonic Tissue to Germicidal Substances: Iodine Trichloride.” Journal of Experimental Medicine 33, no. 8228 (2024): 45–52. https://journals.sagepub.com/doi/abs/10.3181/00379727-33-8228C    

A. E. Gillam, R. A. Morton. “The Absorption Spectra of Halogens and Inter-Halogen Compounds.” Proceedings of the Royal Society of London 124, no. 794 (1929): 604–615. https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.1929.0141  

M. Raquel Domínguez-González, et al. “Evaluation of Iodine Bioavailability in Seaweed Using in Vitro Methods.” Journal of Agricultural and Food Chemistry 65, no. 38 (2017): 8435–8442. https://pubs.acs.org/doi/abs/10.1021/acs.jafc.7b02151    

Lidunn Mosaker Boge, Veronica Nagelsen, IMR, et al. “What Scientists Know About Iodine in Seaweed.” Nofima. August 30, 2022. https://nofima.com/results/what-scientists-know-about-iodine-in-seaweed/  

Inger Aakre, et al. “Bioavailability of Iodine from a Meal Consisting of Sushi and Wakame Salad: A 48-Hour Urinary Excretion Study.” Foods 12, no. 19 (2023): 3689. https://onlinelibrary.wiley.com/doi/abs/10.1002/fsn3.3689  

Marthe Jordbrekk Blikra, et al. "Iodine from Brown Algae in Human Nutrition, with an Emphasis on Bioaccessibility, Bioavailability, Chemistry, and Effects of Processing: A Systematic Review." Comprehensive Reviews in Food Science and Food Safety 21, no. 2 (2022): 1517–1536. https://doi.org/10.1111/1541-4337.12918 

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The Supplement Scoop blog is written by Kate Mahoney, FNTP, FSS, a food-first dietary supplement expert, functional nutrition practitioner, and former international functional nutrition instructor with nearly 30 years of experience. Her mission is to empower everyone with the ability to identify the less than 15% of supplements worldwide that are worth using, with the hope that doing so will lead to improved supplement quality and effectiveness around the world. To that effort, in 2020, she founded the Supplement Academy to provide health professionals and consumers around the world with comprehensive and unbiased dietary supplement information and education.

In her free time, Kate is a Muppet whose inner spark is rejuvenated by nature, dancing to super loud music with friends, caring for her rescued feline furbabies with her beloved spouse, and enjoying delicious homecooked food with loved ones.