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Thyroid UK
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Kelp’s benefits are not without risk

I am more than happy to accept there are benefits from taking kelp supplements - the research convinced me to add some to my diet - just a low dose of 200mcg / day just around the RDA so no big deal in the scheme of things.

I also took on board the very clear advice to dose up with selenium at the same time and I took 200 mcg.

On 2 occasions the selenium 60 day supply ran out whilst keeping on the kelp and I did not think it would have been any big deal to carry on for what was only a matter of a week .

A similar gap arose later on ending up with more kelp minus acccompanying selenium.

A small reaction arose identical on both occasions - and I for one have decided to not take a risk any longer over kelp.

Magnesium seems to have proved far more beneficial for what I was looking for.

I am only stating this as kelp at tiny RDA levels may for some (minority?) be more “invasive “ than I for one was prepared to imagine. It may be that selenium “neutralises” perfectly the downsides but I dislike the idea of having to take selenium for life for this reason.

This is my gut feel , but some have argued strongly here to be cautious and I am comfortable to agree with those saying this .

5 Replies

Something that we keep saying on here - do not supplement with iodine/kelp unless tested and found to be deficient and only then under the guidance of a practioner.

Even taking "just a low dose of 200mcg / day just around the RDA" can be way too much. Iodine is easily obtainable through diet - 200ml of non-organic milk plus one yogurt gives between 100-200mcg daily, 120g of haddock gives 390mcg.

bda.uk.com - foodfacts - iodine


Can I ask what the 'small reaction' was?



200mcg iodine is not a low dose. The max RDA is 150mcg. If you are taking thyroid medication you should get the iodine you need from the meds and diet.


Clutter, there is a range of advice that suggests possible dosing of iodine form zero (where many on these threads place themselves ) to over 50 mg for those following iodine protocols. I can understand all arguments including yours and those who articulate the very top end.

I am just saying that I am moving from being quite risk averse my view on 200mcg to very risk averse ie not supplementing.

I don’t see 200mcg as any real risk if you are taking selenium.

I fully respect the views of those (and there are many) who view this differently.


The other thing I meant to add is that looking to supplement with more iodine is a lower priority than maxing out your ability to convert well the iodine you can take safely on board.

My experience is that use of the right supplements does make a direct and immediate positive impact and removes the need to consider further iodine supplementation.

It may be some/many due to genetics can take on extra iodine in possibly high quantities - but there has to be a

Measurable benefit.

When I stop taking any of magnesium / black cumin / beef liver i immediately notice it. I notice little to no difference for kelp or for all the

Other supplements tried to date.

I think the industry needs to take a very honest and measured assessment over the multitudes of supplements out there and I include in this list the following:

Cod liver oil

General multi vits including b/c/a/d/e

Dried collagen


Liver bile capsules

And the list goes on and on

They all sound good in theory so you take them at great cost and the. You stop taking them and notice little to no difference.

A very personal view and no advice intended and for everyone who finds any of the above helpful I am only too delighted. We can only move forwards by expressing our views as honestly as we can :)


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