I can only talk about this from my experience with a sister of a very close friend who was diagnosed with borderline personality disorder. Aside from describing the disorder, which you may already know, the medications they are put on slows down the metabolism making it very easy for them to gain a lot of weight. I also believe they may have symptoms of hunger or cravings for sweets, which could be caused by the meds or just part of the affective disorder.
Once they have a weight issue, they're prone to all the problems that accompany obesity. As far as foods they really are subject to whatever they are genetically inclined to express.
Hormonally, the medications can cause problems with ovulation and fertility but I'd have to do more research to give an adequate answer with a resource.