I have also been experiencing breast lumpiness since starting using Lugol's 3% Iodine solution. I am not taking it internally but painting it directly on the breast. Prior to this I was suffering from painful breasts, around ovulation until period. All this started when I stopped breastfeeding my 3 year old daughter. However prior to painting Iodine I have never experienced breast lumpiness like this. I also take DIM, B(50mg)complex, transdermal magnesium, vit c and selenium. Has anyone experienced this? I also developed heart palpitations too. I am very concerned as it seems my symptoms are getting worse and not better. Any advice would be appreciated.