Fibrocystic breast disease (also called fibrocystic breast changes) is a common and often painful non-cancerous breast condition. Some women have experienced improvement in, or elimination of, the lumps by completely removing methylxanthines (caffeine, theophylline, and theobromine) from their diets for one to six months. For women over age 45, it may take longer (a year or more in some cases) to see improvement. Methylxanthines are present in foods and beverages such as coffee, tea, colas, and chocolate, and in some medications. Merely cutting back on methylxanthines is less effective than avoiding them completely.
Nutritional supplements that have been found to be beneficial for fibrocystic breast disease include vitamin E, thiamine (vitamin B1), and iodine. Consult your doctor to determine the appropriate dosages, particularly in the case of iodine, which can sometimes cause adverse effects at the dosages needed to be effective.
Source: Nutritional Medicine