You can supplement with iodine by putting it on your skin. For instance, you could use Wombats high iodine cream.
I had cancerous spots from the sun on low iodine. The skin just looked different than the surrouding skin. When you put iodine on a spot like that, the spot swells up. I put iodine 5% or iodine in lanoline on it daily for about two weeks after which the spots would slowly dissolve.
Lugols is abrasive
15% Lugols is abrasive to the skin. You can put on one thin layer every other day without damaging the skin. If you apply oftener, the skin cells that touch the Lugols will die. The amazing thing though, is that your skin will repair looking better than before it got damaged. Damage by Lugols repairs itself from bottom to top and it leaves a scarless, spotless skin.
Lugols 5% can be put on the skin daily without a problem. To make 5% Lugols from 15% Lugols, simply add two parts water to every part Lugols 15%.