There's an odd thing that goes on with this disease - we all "know" that a healthy lifestyle will help to prevent disease, but we also know that the researchers who work on *this* disease tell us that there's no evidence lifestyle modifications will affect our risk in pregnancy.
That's because this disease appears to be set during implantation, which seems to be governed by a unique part of the immune system that's just for managing placentas. It makes sense that we'd have this, since reproduction is a time when we simply have to cooperate with a foreign organ, and it makes sense that it would be broadly isolated from impact from diet and exercise, since eggs used to come with all that was necessary to develop an entire new organism (think of how chicken eggs get no further input between being laid and being hatched!). During the initial development of the placenta, the pregnancy isn't really drawing down much in the way of maternal resources, and it's later in the pregnancy when the fetus begins to demand more than the placenta can ferry (because the implantation is not working properly) that we start to see symptoms.
That said, you'd way rather go into a pregnancy healthy than not. If the placental development doesn't proceed normally, recovery from a nasty acute pregnancy condition is going to be much easier in a fit healthy young woman. If you know you're a salt-sensitive hypertensive outside of pregnancy, then odds are one way that you manage your underlying conditions is by eating less salt, but that isn't going to affect the course of your preeclampsia so far as the best research says at the moment.
(BTW, eating eggs - which have albumins in them, mostly ovalbumin - doesn't support the liver particularly. But they're yummy.