Depends how you want to decide. Per tablet, Iodoral has 12.5 mg iodine/iodide, while Prolamine has 3 mg iodine. Standard Process products have their detractors, but I've used them and trust their quality. Take what you're comfortable with. Know that if you want to take higher doses with the Prolamine, you may soon have a problem with the 20 mg calcium per tablet. That calcium has always been my downfall with them.