I've been on Lugols (8 drops daily) since Feb 2007. It's working great to counter hair loss but I have to continue taking it, otherwise my hair loss volume reverts to > 10 strands a day.
BTW, doing abdominal exercises (sit-ups, horizontal or vertical* upside-down) helps to promote hair growth. This worked for me. Others have reported grey hair turning back to original color. I guess it's due to more blood to the scalp.