As Barbara Wilson-Clay pointed out, fibrocystic breasts are not a
"disease". They are a normal variation. According to one of my gyn texts,
the condition occurs due to hyperplasia of epithelial cells and fibrous
tissue, probably r/t hormonal influence.  In my present practice, I see
lots of perimenopausal age women, and lumpy, sometimes tender breasts
usually seems to be much more problematic for this group.  I will have to
go thru my notes, but I believe that there is research to support
decreasing or eliminating caffiene to decrease symptoms such as
tenderness. I recently saw a 45 year old who breastfed all three of her
children for at least a year each. She is someone who makes cysts (two
previously aspirated, one currently present, palpable, and also seen on
her mammo). She is one of those women who have experience cyclic breast
tenderness for several years now. She states that it was completely gone
throughout breastfeeding (which also suppressed her periods for several
months). Though I don't recall seeing any research on fibrocystic breasts
and breastfeeding, her experience does not seem unique to me, and I think
that it is reasonable to reassure a mom with such a history that exclusive
breastfeeding may decrease cyclic breast tenderness.

Back to caffiene: Anecdotally, I have had several clients tell me that
their symptoms of cyclic tenderness disappear or dramatically decrease
when they eliminate caffiene.  Some women also find that adding 600 to 800
IU vitamin E is also helpful.

 Ione Sims, CNM, IBCLC