To some extent the anti-iodine stance is based as much on greed as fear. Notice those mentioned being against "elemental" iodine also sell their own products. Since iodine is readily avaiable in various forms, it is hardly something a person can make an exclusive product. Of course, fear is also a factor. Most of us can remember that little brown bottle with the skull and crossbones that set in the top shelf of a lot of homes, brought out to treat the "boo-boos" of active kids from the pre-computer and video game age. I admit it took me a certain amount of courage to step out of a box built from old myths and prejudices.
Personally, I like the idea of the so-called "elemental" iodine best. My experience is limited to Lugol's Solution, but I like the idea of taking an exact dose with known components. Both kelp and the so-called tree iodine are unknown quantities and qualities. I know how much iodine I am getting in every drop of Lugol's. It is my choice to determine the best dose. With kelp there can be various amounts of iodine present in the raw product. If the kelp has been standardized to a specific dose, then it has been highly refined and bares little resemblance to the orginal sea plant. What concerns me the most about kelp is the fact that one of its functions is to filter sea water. While this works well with normal aquatic waste products, it also means kelp is at the mercy of our pollution of the oceans. Samples of kelp have been found to contain arsenic, mercury, and petrochemicals at levels unsafe for human comsumption.
Tree iodine from the Black Walnut tree is even a bigger crapshoot. The amount of available iodine from the tree has never been proven. Black Walnut hull tincture contains juglone, an effective antihelmentic . The tannins that give the acrid smell and feel of the hulls can tan an animal hide, but are not really good medicine. Using so-called tree iodine is taking a wild guess at how much (if any) iodine is present.
As with other alternative health and natural healing protocols, iodine supplementation requires careful study and a leap of faith. Those who are fearful need to avoid iodine or anything else that feeds their fear. Their fear would probablly cancel out any positive effects of iodine or any other protocol due to the stress and toxic load fear creates.
Iodine supplementation will rarely be a cure-all in itself, but when combined with a lifestyle dedicated to good diet, proper cleanses as needed, and a careful use of supplements can help bring the body back into balance so it can heal itself. Scare tactics, especially those used to generate sales of alternative products is hardly in the spirit of true healing and an open-minded attitude.