Re: preventative of what?

Iodine is not purported as being a "cure-all" as you've asserted. There is no cure-all, except death itself -- it does cure all indeed. One other cure-all is knowledge, and if you get enough of it, you can be your own cure-all.

Iodine rather, is an opportunity, for many things. Mostly, its an opportunity to learn. An opportunity to learn how to read both from published works of several MD's who know of its benefits, and an opportunity to see what others have written here, their personal anecdotal experiences.

What a person gets out of it, is largely dependent upon what they invest in it, on a time basis. Asking others for guidance is always an option, but those who've invested lots of time learning for themselves are not likely to continue to repeat the same answers, over and over, for every anonymous Joe who writes a question. I think they have some reasonable expectation that a person will read the FAQ, BSA messages and other messages that are rated with R's.

Iodine is a good practice fodder for becoming independent. Once a person master's what we know about it, it enables them to easier tackle other subjects. But it does require a time commitment, and those unwilling to make that commitment are likely to need to be told what to do indefinitely.

Best of luck to you in your learning, should you decide to go that route.