Kelp.
Or anything with iodide.
I think the left coasters should all consider a nice big dose of Prussian Blue. Maybe wash it down with pink lemonade. /sarc
Or table salt- use extra with each meal.
IIRC some people have suggested using betadine. It’s that orange colored iodine solution they use in the OR.
You can buy it in the drug store and paint it on your belly. I don’t remember the details but I’m sure they’re available on the net.