I have been told to take lugols iodine for my seborrheic dermatitis, if you have been taking it for a year already and it hasn't helped then I'm not sure if it's going to help me.
Have you done any parasite cleanses or liver flushes? I really think seb derm benefits from them. Personally I believe seb derm is caused by candida overgrowth which the person who suggested iodine to me said was linked to iodine deficiency. Others have also suggested it is caused by pathogens in the gut. Psoriasis and seb derm are extremely similar and psoriasis suffers have cured their issue with the use of cannabis oil.