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 .