No one ever developed cancer due to a deficiency in chemo. The same cannot be said about iodine, Vitamin D3 and other natural essentials that many of us are deficient in due to our SADS diets, depleted soils and over-processed foods on our grocers shelves.
I might also note that while I am not familiar with oxidative damage due to iodine I have seen studies that indicate oxidative damage due to iodine deficiency. For example: