Okay, I understand why sodium makes you retain water, but what is it about TOM that makes you retain water? Is it a certain hormone?

For me, the water retention starts the week before, and once TOM starts, I swear I am on the potty every 20 minutes.

Ahhh, I know what you mean! I do the same thing! I don't know for sure, but I'm guessing it's because your body is gearing up to lose a lot of fluids, so it keeps as much as it can beforehand. It sure is a pain though. On the plus side, I try to be extra good and push extra water that week, and then when the TOM has flown the coop I often find that I lose an extra pound or so, probably in water weight, but it's fun

ugh! i'm so bloated right now...I hate TOM this month - a lot more bloat than last month...my tummy is so distended right now it's not even funny! go away go away!!!