After constantly being asked about kelp and other sea vegetables in the context of iodine supplementation, I decided that it was time to address the elephant in the room.  The constant push to take Kelp and other Sea Vegetables to supply iodine in the diet has been concerning to me.  While sea vegetables may offer iodine and other nutrients, they also risk a high exposure to toxins.

Natural News Labs published this article on the testing they performed that showed high levels of cadmium, arsenic, lead, mercury and copper.

A UC Davis study finds high arsenic levels in kelp supplements.  

A recently published study of herbal kelp products by UC Davis public health expert Marc Schenker concludes that some kelp supplements may cause inadvertent arsenic poisoning and health dangers for consumers, especially when overused. Schenker and two researchers evaluated nine typical herbal kelp products and found higher than acceptable arsenic levels in eight of them.

Dr Alexander Haskell states in one of his youtube videos on iodine that he attempted to obtain a 3 mg capsule of kelp from Gaia Herbs to use in his practice.  After much investigation, Gaia returned to him and stated that attempting to put this amount of kelp in a capsule would put them over the legally allowed limit for arsenic.

Our seas are becoming so polluted with chemicals, heavy metals and pesticides.  The organization Sea Web offers some troubling information about what we are facing with anything that comes from the sea – be it sea veggies or seafood products.

From an old blog from Dr Brownstein in 2007 that is no longer online:

Caution With Kelp Supplements

My research has shown that after testing over 4,000 patients for their Iodine levels, over 96% of those tested are significantly low in iodine. Many patients ask me if they can take kelp instead of iodine. The amount of iodine in kelp can be variable. Furthermore, I was always concerned that kelp supplements may contain toxic amounts of arsenic or halides. I have tested 2 kelp supplements and found very elevated arsenic levels in both items. Both of these products were marketed heavily and sales in the millions of dollars were reported. When I contacted he manufactures of these products, neither returned my phone calls. Remember, if kelp is grown in a polluted area of the ocean, it may contain elevated amounts of these pollutants. New research has validated my findings.

Researchers at the University of California/Davis found that eight out of nine kelp supplements contained abnormal levels of arsenic (Env. Health Perspectives, April, 2007). The researchers began to look at kelp supplements after a patient presented to the UC Davis clinic with a myriad of complaints including memory loss, hair loss and fatigue. She was found to have very high arsenic levels which was traced to a kelp supplement she was taking. After stopping the kelp supplement, her arsenic levels gradually declined and her symptoms improved.

So, what can you do? IF you are low in iodine, take a pure iodine product that is not contaminated. Lugol’s solution or tableted Lugol’s solution (Iodoral®) have both proven safe and effective in my practice. Kelp can be an appropriate iodine source if the kelp has been tested and found free of toxic elements. I would be very cautious about taking a kelp supplement unless the manufacture is consistently testing the kelp for purity and consistency.

Another research article on the Safe Use of Kelp Supplements shares that arsenic is indeed found in these supplements.  While they are not totally negative on the issue it does reinforce that arsenic is an issue.


Fukushima continues to be an issue especially for those on the west coast.   The nuclear reactors continue to leak toxic radioactive materials and have been since 2011.  Even in March of 2016 we see news reports of its toxic waste dump into the ocean.

While health food enthusiasts continue to support the use of kelp for iodine let’s put this into perspective – toxins aside.  Sea vegetables on average have 500% of the RDI of iodine for a daily diet.  That may sound like alot, but the RDI is 0.150 mcg of iodine.  500% of that would be 0.750 mcg of iodine.  This is far from a high amount when considering that the iodine doctors (Dr Abraham, Brownstein and Flechas) have been using amounts from 12.5 mgs up to 300 mgs (for cancer patients) in their practice for years as a daily supplementing dosage.  The average member of my Facebook Iodine group is reporting daily supplementing of 50-150 mgs + per day.  You would have to eat a lot of sea veggies to match this level.

Final Thoughts:  If you are determined to consume these products, then I would suggest that you do a few things.  Contact the manufacturer and ask them what testing is done.  Ask them to see the reports outlining the levels of halides and other nutrients.  Also ask them if they test for radiation exposure.  If they cannot provide these things then I would pass on purchasing and consuming their products.

If you are looking to supplement with iodine the best way to do this is through an Iodine supplement like the ones I offer in my store.    Make sure your supplement is Lugol’s formula for both iodine and iodide because the body needs both forms.  (See my previous blogs on iodine for more information on supplementing).