The issue is that the cofactors must be the correct forms of these elements—Iodide, Molybdate, and either Selenate or (for me) Selenite ( I took Selenate, which Greg said works for two years before switching to selenite); and for proper absorption, you must take them without food, and away from citric acid, as vitamin C, or lemon juice, etc as well.) Strangely, though I’d taken a form of iodide that seems to work for many for years, there was another form that gives me much more of a start-up reaction, than this, that seems to work better for me. Then too, I didn’t fully understand how the influence of all these can be read—to a large degree apparently—by Greg, as the numbers of a Full Thyroid panel that shows Total T4 and Total T3. The web site goes through all this information. Working with Greg and testing, testing, testing can assure you are on track. It’s something I’m much more tuned into now. Good luck!