January 2019 – Pseudo Randomness

TLDR: No.

The long version of the answer is that while seaweed does in fact contain a large amount of iodine, the potential harm of regular consumption outweighs the potential benefit for the following reasons:

Most seaweed manufacturers don’t test or don’t indicate the exact iodine content. If iodine is the main reason for consuming seaweed, you should know much you’re actually getting since there’s a wide range for content.
Some seaweed is contaminated with radiation. The problem here is again the lack of testing or availability of results. It might be true that some seaweed is free of traceable radiation but given some is not, how would you know which one is the one you’re eating? If the test results are available, they need to be sampled frequently and inclusive to be useful which is very rare.
Most seaweed is contaminated with heavy and harmful metals like arsenic (inorganic). The issue with a lot of these metals is that there’s no established safe levels for products like seaweed. This is further complicated by the unavailability or inaccuracy of this data from sellers. Even when the data is available, it is done with a lot sample instead of for every batch and could be done just yearly or less frequently.

In the rest of the article, we will focus on inorganic arsenic to make the case against regular consumption of seaweed but other heavy metals can be considered to add more factors.

Types of Seaweed

The above issues are common to all types of seaweed but there are some differences among the types. Of all types hijiki is known to be the worst for arsenic. In one study of five types of seaweed, only hijiki had high enough content of arsenic for their detection method. [1] Another test by an Australian food agency also found significantly more arsenic in hijiki than other seaweed types. [2]

Other types of seaweed which are considered safer than hijiki are: kombu, wakame, nori, and laver.

The Numbers

According to [6] and [7], adults need 150 mcg (micrograms) of iodine daily. Pregnant or breastfeeding women need 200 mcg or more.

As mentioned above, there’s no safe level defined in the U.S. for arsenic in seaweed but here are some other defined levels for reference:

Drinking water by EPA and WHO: 10 ppb (part per billion). The interesting thing here is that even at this level, there are some studies showing it’s still harmful. [8] Also any test on seaweed will usually have about 100X this amount or more.

Eggs, chicken, and turkey by FDA: 0.5 ppm (parts per million)

See [9] for more on declared safe levels: https://www.atsdr.cdc.gov/csem/csem.asp?csem=1&po=8

Now for comparison, a heavy metal test by one seaweed producer ranges from 0.4 ppm to 2.28 ppm: https://www.atsdr.cdc.gov/csem/csem.asp?csem=1&po=8

This is one of the few good sellers that actually tests and publishes results. Who knows what the levels are for companies that don’t even publish these numbers

Alternative Iodine Natural Sources

What can you use if you don’t feel comfortable about seaweed? It turns out there are a lot of other healthy options:

Fish: While fish has its own issues with heavy metals, it turns out the percentages are much lower per weight. See study by Australian Food Authority for a comparison. [3]
Dairy: Good-ole milk has more benefits than you thought. In fact the lack of iodine is one of the major downsides of using milk alternative products according to one report. [4]
Bread: One study in the U.S. found surprisingly high amount iodine in some bread brands. [5]
Eggs: Eggs are another good source of iodine. One egg provides 16% of the daily value.

For more sources of iodine, see [6, 7]:

Another option to consider according to some is Lugol’s iodine formula, nascent, or a supplement in pill form.

This seems to be more for those who have a diagnosed deficiency or if you know your regular food is lacking sufficient amounts of iodine.

Another reason to consider supplementation is high halogen content in your diet or environment. Because halogens are reactively close to iodine they can take its place in various molecules in the body. When this is happening a level of iodine saturation is needed to replace them and detox.

Lugol’s iodine happens to be the most recommended type for supplementation because it has been used for for more than a century gaining trust and lowering cost. You can see more on these options in the following document by Stephanie Buist: https://jeffreydachmd.com/wp-content/uploads/2014/03/The-Guide-to-Supplementing-with-Iodine-Stephanie-Burst-ND.pdf

Other Foods of Concern

When it comes to inorganic arsenic, it seems that after seaweed and fish, the most significant offenders are rice and fruit juice. Rice seems to be a real issue that the FDA proposed a new standard of 100 ppb for arsenic. For more on rice and fruit juice see the following:

Rice: https://www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm319870.htm

Apple juice: https://www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm280209.htm

Pear juice: https://www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm275452.htm

Conclusion

The bottom line from all this research is that it’s difficult to to know that eating regular seaweed will cause more benefit than harm. It’s safer to get the needed iodine from other natural sources where there’s no risk for heavy metals or radiation.

This conclusion is about daily or regular consumption but occasional consumption like when having sushi once a week or less frequently should be safe.

Lastly, it seems like there are some efforts to standardize heavy metal testing and make that public like the following website but none of this seems recognized or credible yet: http://labs.naturalnews.com/heavy-metals-chart-superfoods-sea-vegetables.html

Month: January 2019

Should you take seaweed as an iodine supplement?

Types of Seaweed

The Numbers

Alternative Iodine Natural Sources

Other Foods of Concern

Conclusion

References