Hv, I prefer to get my nutrients from food, but as the food grown in my country, even what I grow in my own garden, is grown on Iodine deficient soil, so I am not getting enough Iodine from naturally occuring sources, hence why I supplement.
I also needed to be acurate with my dosing because of the various conditions I was treating, FBD and uterine fibroids, in particular.
I will supplement whatever I need for my health, that is not possible or practical to gain from my diet. I reccomend anyone who is going to supplement with vitamins, minerals or anything, to do their research and always approach and proceed with a good measure of caution.