Does iodine help with breast pain?

Two small trials found less breast pain with high doses of iodine in women with fibrocystic breast disease, which causes lumpy and painful breasts.^[1]

In a trial of 56 women, 65% had less pain after 6 months of iodine, against 33% with placebo.^[1] In a trial of 111 women, 3 mg and 6 mg of molecular iodine a day reduced pain by month 3, but 1.5 mg did not. More than half of the women on 6 mg had a clear drop in pain.^[2]

These doses are above the US upper limit of 1,100 µg a day, and they should only be used under a doctor's care.^[1]